(I am Not Counting just Buying Stuff--which perhaps I do too much of, or Online "Research", but only if something has Actually Gotten Done.)
1. Hung right surround speaker on wall for the first time in 14 years since since I got the speakers. Previously it had been sitting on the equipment rack right to my side, hardly surround at all. I made a goal of doing this in January, and just barely pulled it off. I find it hard to hang things on walls, but I believe I did a great job with two stud-mounted screws for the speaker mount. I ultimately came up with a wiring scheme in which the teflon coated silver plated 14g wire is twisted loosely around the ball of the clamp, so when unscrewing it, hopefully at least, it doesn't fall to the floor.
2 Did 2 generations of Needle Drop experiments on the Stereo Review Test Record 12 on my LP12 based turntable. (After getting the record cleaned by a gracious audiophile friend on his Loricraft Record Cleaner.) From the first generation, a friend determined among other things the horizontal and vertical arm/cartridge resonances were 13+ Hz, much too high. Also the horizontal low frequency resonance is disturbingly undamped.
3. I applied cloth Hockey Tape to the Ittok tonearm and integral headshell to increase mass (to lower the arm/cartridge resonant frequency) AND to dampen the transmission resonances of the much much too resonant undamped stainless Ittok arm. This resonance improvement was spectacular, and in combination with the clamp I use have elevated my Vinyl Playback to Best Ever For Me, exceeding in almost all ways the sound of my PSX-800 rig (which may actually have been noticeably more speed stable...but otherwise similar sounding) also helped by the best preamp I've ever had by far (the Emotiva XSP-1) and the best speakers and tuning, etc. Additional tests continue to show the superiority of clamping vs not clamping. I believe the common audiophile notion that you can have too much damping is almost completely wrong, and the Linn notion that you want zero damping is total nonsense. The more complete damping the better, and that is the approach followed by all the megabuck turntable systems of the past couple decades (except Linn). My friend in France discovered Hockey Tape as an ideal damping material for turntable parts many years ago also applied his knowledge to the record cutting system of a famous mastering engineer, leading to a Grammy winning recording.
4. The second generation of Needle drop showed the vertical resonance had dropped by 1 Hz, but the lateral resonance only 0.5 Hz, because the arm's lateral mass is about twice as much as vertical, which is easy to imagine, the entire central base of the arm pivots only in on the horizontal axis. (At least another coat of Hockey Tape is desirable at this point, to reduce mass another Hz. Maybe two more coats. And, an extra dose, possibly combined with coins, application to the horizontal top bar of the pivot (which doesn't move except laterally) in order to give an extra mass boost to lower the frequency of the horizontal resonance.)
5. Determined that all 4 (Optimus) RCA LX-55 surrounds speakers sounded best with the speaker ports completely stuffed. I did this stuffing using folded dark grey foam backing rod, which looks cool I think, and could easily be removed. The bass needs as much reduction as possible, even with the Small speaker setting (and permitted by it as well, because of the near ceiling positioning of the speakers, which is unavoidable in the kitchen.
(Not Counted.) I damaged one LX55 speaker in the process, and replaced it with my final #5 unit, which I had to dig out of storage. The damaged speaker had very brittle woofer surround, and the pliers I was trying to use to remove the final straw that had been in the port but fell inside, I barely touched the foam surround and it cut like beer foam, and there was no going back. Now the damaged speaker is in the workshop for testing with my two varieties of replacement woofer I obtained, as I was planning to do anyway for all the speakers eventually, once I've determined the best replacement and modification strategy. One of the replacement varieties I obtained is Italian made and actually has flat response to 5kHz, where most 5" woofers have a serious dustcap resonance peak there. I found out about both by read ing LX-5 replacement stories online. My LX-55's are virtually identical to the original Optimus LX-5's, I think, but so LX-55's were sold you can't find out much about them. I bought an additional NOS LX-55 online for comparison and experimentation and I ultimately plan on have 6 surround speakers anyway.
(Not Counted.) Also for future surround speaker experimentation, I obtained a pair of the famous Infinity "Walsh Tweeters" (not really a Walsh driver, as those most face downwards into a box load, but these Infinity drivers are famous and special in their own right). These are normally crossed over at 10kHz on the actual RS-2000 Infinity Monitors (which was possibly the first speaker I fell in love with, or lust, sometime around 1971), as I finally determined after finally being inspired to buy the tweeters, from a well known refurbisher on eBay. (He packed them AMAZINGLY well, every detail of packaging optimized.) So I know own the most exotic part (and actually the only part I find even remotely interesting now) from the first speaker I fell in love with. I also determined that in the original loudspeaker, they are crossed over with a simple capacitor. It's possible with a steeper crossover, and for low power surround speaker use, they could be crossed as low as 6kHz, which would make a perfectly omnidirectional system out of the LX-55 woofer after removing the problematic Radio Shack "Lineaum" tweeter (which, actually, I don't have very much respect for anymore, it's full of suckouts below 10kHz and there is virtually nothing above 10kHz). This is currently my "ultimate" idea for surround speaker (small woofer plus magical omni tweeter), but I'm not sure I'll get to it this year. Lots of testing will be needed, including to determine how far down the tweeter can play well, and this needs to be done with utmost care.
6 & 7. (6) Determined that the previous anti-skate level on my Linn turntable was inadequate, in several ways, including my usual blank disc, and a new full sided blank disc. In the final adjustment, I set the Ittok anti-skate to maximum, a reading of about 3.2. This produces stasis at all parts of the blank record...sometimes there is a back and forth but the arm never gets carried away inward as it does at lower anti-skate settings. My actual tracking force is around 2.2g. This new anti-skate setting is no doubt also part of the best sound ever. Also, it almost completely eliminates the problem of the cartridge going haywire, as it was ALWAYS doing, at the center of records. I now observed that (7) to be the side of the wide Dynavector 17D3 cartridge body hitting the clamp and bouncing slightly back away from the center, over and over. But, with the better anti-skate compensation, the cartridge body is better centered and therefore further inwards relative to the stylus, as it should be, and doesn't hit the clamp. This is great for playing most records now, but sadly it still doesn't work on all records. I could possibly benefit from an arm lifting device like Q Up.
8. I cleared the old VCR player and stack of recordings and stuff 18 inches high from atop the kitchen rack away. This means I can actually see the wall attached right surround speaker more clearly, and improves the sound greatly (it was very very dark sounding before, and of course I couldn't even see it). I also twisted the speaker more downward because the high frequences are very reduced below the axis of the speaker. So now it is pointed 35 degrees or so toward the listening position. This improved the darkness, but it may still be the most dark sounding of all the speakers, but it's also hard to tell fairly. But clearly the Audiogeorge modified units, with tweeter phase made uninverted and woofer choke removed, sound desirably brighter, I have guessed, reversing my previous opinions. I think this is primarily because of the boundar positioning. I plan to remove the right surround speaker from the wall mount, test the tweeter better, try reversing the tweeter phase, as a first step. I also have a brand new (NOS) speaker unit to compare it to, and the damaged woofer unit. The VCR has moved underneath the kitchen table where it will be part of a table rack I made years ago along with whatever I use as the Kichen Front amplifier, and possible the surround amplifier too (which would probably be the Yamaha receiver when I get a new processor).
9. I have positioned a new-to-me surround processing unit atop the rack, but pushed far back, and the unit is quite low, for a special kind of surround processing (not the usual modern processor stuff, but more on that later) that merely expands 5.1 recordings to 7.1 speakers so I can enjoy all my surround speakers with music 5.1 recordings. The "New" unit is a NOS SSI System 1000 II stereo processor. It is intended for generating 5.1 channels from 2, a mid 1980's early surround processor. It proclaims Dolby Surround, and this is nearly the first implementation. Basically it uses a Hafler-like matrix to produce the side surrounds, combined with a bucket brigade delay system that uses Dolby noise reduction. I'm unclear if the noise reduction is use double ended (to reduce the noise from the early bucket-brigade delay) or single ended, to soften the sound of the back. Anyway, my idea is to use this processor on the OPPO side surrounds as if they were the front speakers, and then take the "surround" produced by the processor for the back surround speakers, thereby expanding a 5.1 signal as on all DVD's into a 7.1 signal for my 7.1 speaker arrangement. I read someone suggesting an idea like this. Also it's possible simply to duplicate the sides for the backs (side surrounds and back surrounds playing the "side surround" signal). I'm going to set up a switch (already in place) to select 1. derived back surround speakers as I just described using the SSI processor, 2. duplicated signal for the back surrounds from the side surround signal, 3. routing the sides TO the backs alone for ambisonic and ambiphonic recordings, of which I have a few, and 4. actual discrete 7.1 which the Oppo produces from some Blu Ray discs, such as the AIX Blu Ray sampler I have.
(Not Counted.) I have also read a lot of reviews and other information on more modern Surround Sound processors. Unlike anything I've had, now multichannel audio input is now handled through HDMI, and many units come with advanced room correction. I'd like to have at least Audyssey XT32, and also some kind of loudness eq system like Audyssey Dynamic Volume and EQ. And of course some way of generating 7.1 and at least 9.1 systems (including front wides) from 5.1 sources. I've come close to buying a few models like this on eBay, and also from an audiphile friend, but I'm in no hurry, as I want to get the speakers and other things optimized first, and I look forward to playing with my home brew 5.1 to 7.1 conversion--which provides many direct adjustments perhaps unavailable on modern processors. I also checked out the features of my Integra Research RDC7, obtaining the actual manual for my "Upgraded" unit. It does have analog multichannel inputs (only) and you have to use a custom snake cable to connect them through a DB25 connector. Not only does it not have 7.1 inputs (which even my Yamaha does), it appears not to have precisely Dolby Pro Logic IIx (only II), however what it is similarly able to derive 7.1 channels from 5.1 sources. I was long planning to use RDC7 as my "ultimate" surround processor but I now understand the important features it doesn't have, like HDMI inputs, 7.1 input channels, and ultimately I do want to have at least a 9.1 setup with wide channels.
10. FINALLY (after 4 years of chipping away on this project) I re-established the Queen's Room (guest bedroom) stereo, with Tripplite power strip horizontally mounted inside the desk underneath shelf with 8 outlets. The small amplifier is started with a trigger voltage generator: a 12V DC linear type power supply wall-wart, feeding a silicone wrapped bleed-off resistor calibrated to provide shut-off in about a second. That is switched by an Insteon Home Control On-Off module, which I have programmed my Universal Devices controller to be controlled by the Insteon On-Off wall switch which controls the light and fan. Once the light is turned on, and you wait 2 seconds, you just tap the light switch a second time and the stereo (featuring a tiny Parasound amp and the Gallo A'Diva speakers) comes on, with audio signal from a Sonos Connect, which is set up to play the FM tuner from another room, the Pioneer F-26 which is tuned to KPAC-FM, the all classical radio station. Then, when you turn the lights off, the stereo also switches off. This is great for visits and my girl friend loved it when I demonstrated it last week. I didn't mention that I had many other ideas, so you could also play the stereo when the lights were off and turn the stereo on and off without turning the lights on or off. But I decided not to make it any more complicated right away. Now, it's very simple, and she likes that. This was also a major home improvement project. The longest delay was determining the proper resistor size. I waited until a computer club meeting to do that. I found the bleed resistor testing interesting but my friend thought it was a waste to use a linear wall wart when a switching type would simply drop the voltage immediately, problem solved. I felt a switching wall wart would corrupt the AC power on the power strip and degrade the audio quality. He thought that concern was silly. But I went ahead and did it my way, finally with full silicon sealing on the bleed resistor. Then it took another year to get around to ordering the power strip AND especially drilling the holes in the cabinet and mounting the new power strip to it, which required another trip to the hardware store to get long enough screws than Tripplite had provided. Despite all the added complexity, the wiring of the setup is much tidier now thanks to the horizontally mounted power strip.
11. Got Roon Set Up. This was big for me, I always wanted Roon, but with my 8 zone Sonos system, I was hardly about to switch to these new fancy streaming systems costing $2k-$20k Per Node. Perhaps, I opinied, I one day when I had lots of time I would set up a Raspberry Pi system with an audio network similar to Sonos in which I could run Roon (see Roon Raspberry Pi). But in Feburary a friend told me that Roon now supports Sonos. Hurrah!!! Before long I installed Roon on my main kitchen Macintosh. Now I can run Roon on my Sonos system, and it works great. Finally it is easy to use Tidal, and know what kind of version you are playing. Generally, I would prefer the plain vanilla PCM I think, but since the Roon/Tidal/Sonos system finally at least does some level of "unfolding" automatically, having MQA is not so much a loss. Maybe it would be a gain in some cases? Anyway, I'm happy that I now have the system I dreamed of having in these regards. I'm getting used to Roon. I hope they continue to imrpove it, and personally, if they do keep improving it, I'm happy paying an annual charge.
12. Bought, tested, and set up an ATI 1502 amplifier in the bedroom now but basically because I wanted a new amplifier for he Revel M20's in the kitchen--where I may ultimately put either the ATI or the Parasound HCA-1500A. I had long been interested in ATI amplifiers, but mostly lusting after newer TOTL signature models. A friend pointed out a Parasound HCA-1500A as I already had in the bedroom would probably be better for the kitchen as well. Anyway, I bought an ATI 1502, one of the earliest ATI models, something I almost bought about 15 years ago at a friend-of-a-friends house. I think it's beautifully made on the outside, looks better made than a piece of General Radio equipment, and I love the big side fins. I did measurements on two days, (the first day of measurements being all in error for reasons I'm unclear of but I know to avoid doing certain things on my ST1700B), showing both to be excellent amplifiers in power, noise level, and THD+N (all the things I can measure on ST1700B and a scope, I didn't have time for other measurements). Amazingly the ATI 1502 is better than the 1500A on static noise level, but in most distortion measurements the 1500A is very slightly better. Overall, but based only on these limited measurements that didn't include distortion and noise spectra and damping-factor-by-frequency, I doubt I'd be able to hear a difference between the amplifiers, and I doubt there's significant difference in the unmeasured areas as well. By choice I'd take the Parasound due to trigger switch and lower distortion, but the ATI may yet have some advantages, we'll see. The one I received is very nice --it looks exactly like the one I passed up on 15 years ago as if it were stored in a museum since then.. And it was packed beautifully with foam-in-place as if it was General Radio equipment too. One can't count on those aspects of an equipment purchase, so it's a happy purchase despite seeing an HCA-1500A on ebay for $499 right after I bought the ATI, and given choice between the two I might take the Parasound. For awhile I considered the additional HCA-1500A also, but then decided to buy an "upgraded" Hafler 9300 with new increased capacitance, which is hard to do in the small chassis. It might be better than my main 9300, we'll see. If nothing else I'll see if new capacitors makes a difference (I've been thinking my Hafler slightly power supply weak, just doesn't have quite the "kick" of the Krell, though it may sound better than the Krell otherwise). The ATI is now set up in the bedroom partly as experiment, but I've decided it makes slightly too much chassis sound and directs it better into the room than the parasound, so I have it turned off, and I'm seeing if my cat tolerates the lack of a warm amplifier next to where he sleeps. I think the Parasound made about as much chassis noise, but it was directed more diffusely so I couldn't tell where it came from. Now I know from experiment this quarter that most of the background hum comes from the power amplfier, and it's something worth fixing somehow. I could have an automated switch to turn the amp on and off, and/or I could refurbish the power supply capacitors in the amplifier. All this amplifier stuff (the new 9300 has just arrived, waiting to be tested) and I haven't gotten around to...well the miniDSP's for one thing. Though I did find this quarter I could run the major linear phase EQ program using Wine on my Mac, at least for now as long as I stick with less than Mojave OS. In Mojave they remove support for 32 bit applications, and last I checked Wine was still catching up with that, however they said they would ultimately support even 32 bit windows applications on Mohave.
13. I added a heat shield to protect my 4x4 video matrix switched (used by my household video network, from 4 kitchen based sources) from the heat from my Yamaha HTR-5970 receiver. It gets plenty hot, even hotter playing mutichannel, with the bottom of the matrix switch getting ominously hot. Not only did this require figuring out how to do this (I had many other plans, and at one point tried aluminum foil, but that was ridiculous) and getting the rack brackets, then rack screws, then labeling and removing enough connections (a lot!!!) to get the paper foamboard squeezed in--and it is very tightly squeezed in and feels about as hard as wood--it would be impossible for it to just fall. Now, not only does the matrix switch stay cool, it almost seems like the Yahama is staying slightly cooler. But I really need to off-load the excess load of the 6 ohm Revel M20 main speakers from the Yamaha. That was the justification for buying the ATI amplifier, though now I might run the ATI in the bedroom, or maybe not.
14. I set up a stepped attenuator to attenuate the Mac computer audio output being input to my Pioneer video recorder. It needs to be reduced because the output of the Schiit converter which feeds the recorder inputs (I use that after a series of digital splitters sends off the digtal to the receiver also) is 2V, and the video recorder inputs expect 1V. Formerly I had some Harrison Labs attenuators, but those aren't necessarily the greatest, and I misplaced them.
15. I performed a series of changes reduced the kitchen system hum level often to as low as -150dB as seen from the Subwoofer EQ now installed in the main rack. I tried lots of things, the ultimate so far was to feed the source signal from the Yahama receiver with a solid ground connection to the Behringer EQ, which is basically the only thing in the system (now) which is actually grounded. I had been isolating that the EQ with an isolation transformer, but it turned out that had been making the ground loop hum worse. I also came up with how to handle other grounds, the FM from the outside antenna which already goes through a high end arrestor outside is now grounded inside to my auxiliary power strip plugged straight into the wall (a Monster) and then isolated with an FM/RF isolation transformer before going into the tuner. Before all these changes, which I think I started in January, the hum was pushing -90dB. Even now it occasionally rises to -135db and I don't know why, but that is far better than -90dB.
16. I have upgraded the Oppo BDP-95 with the latest firmware (over the net, it was a piece of cake) so it now plays up to 7.1 channels on Blu Ray discs which have 7.1 channels. (Apparently all DVD's, even DVD-Audio, only has 5.1 channels.) I first discovered and had to prove that I was not getting all seven channels from the oppo. I could tell the test tone didn't do that, but I figured the error was limited to the test tones and when actually playing 7.1 channel discs you would get them all (including the essential back surround channels). But even after I acquired the AIX Records calibration disc on ebay, I still found the back channels weren't working and confirmed that on a voltmeter. It was also a question of whether the inputs--which require menu programming thats somewhat complex--were actually send all 7.1 channels through the Yahama. It really only has 5.1 input jacks, but if you program some mode you can use another input as the front channels, then you get the back channel inputs where the old fronts used to be. It took some effort, even getting the Yamaha menus to work on the Yamaha remote which I finally did too, to get this to work. But I ultimately verified I was not getting the backs out of the Yamaha using the AIX disc and a voltmeter connected to the outputs so there was no uncertainty. So then I also checked if I was getting up to 96kHz and 24 bits from the Oppo SPDIF digital output. I confirmed that it was doing that using DVD-Audio discs (but not Blu Ray) and the Sencore digital analyzer, which can show the active number of bits too (I was thinking I needed to make a recording and use analyzer software for that, but the Sencore did it directly on the digital signal). So then after upgrading the Oppo both the Test Tone AND the 7.1 output from the AIX blu ray worked. And I was still getting at least up to 96kHz and 24 bits from the digital outputs, though of course with the copy protect bit set so no digital recorders will record the signal (just as it had been before, and I know now for sure I never made a direct digital recording of a DVD-Audio, though I often thought I could, I merely made different analog samplings). Oppo always gave the consumer user the most possible, pushing the envelope of what they could get away with under the noses of the DRM people at movie studios. Even after upgrading, I was also still able to insert and run the Region Free ISO disc just enough to makes my BDP-95 Region Free and I can play may Blakes Seven movies on it. So all my fears about upgrading the Oppo had been unwarranted--I lost nothing--and I gained the full 7.1 outputs from the Blu Ray discs that have them.
17. I performed numerous measurements and adjustments to the Kitchen surround speaker level and delay controls and subwoofer level and EQ adjustments on the Behringer EQ now added for the subwoofer (I can't remember when I hooked up the EQ, that may have been in this Quarter also). Finally I concluded it's best to set the level controls ONLY in the Yamaha, and set the delay controls in both, because the multichannel inputs DO get level control in the Yamaha, but the delay and EQ don't apply to the multichannel inuts. I added but ultimately removed EQ's from the surround speakers themselves partly since I can't use it when playing multichannel discs through my Yamaha anyway (the multichannel input on the Yamaha does no digital conversion or EQ or delay processiong, however it does apply the relative level adjustments) and I want to focus on fixing the unEQ'd response of the speakers first. I've also done lots more listening to surround processing modes on the Yamaha (for 2 channel sources) and multichannel discs than I've ever done before.
18. Visited an audiophile friend, and determined that his system DID reproduce midbass that my living room system is lacking, which I measured and figured was caused by reflection cancellation last year. I determined this by listening to a female vocalist. It turned out that he had a similar cancellation, which he fixed using a different miniDSP model from what I got. He fed a REW-calculated midbass adjustment through that as a different channel into his pair of subwoofers. I had been thinking of doing a similar thing, in various ways. What an inspiration!
19. Measured the damping factor of the Krell using several frequencies and loads and reported to this blog. That was the only thing I've done on the Krell this year...I've switched to playing on the Hafler 9300, and made some minor adjustments to EQ's and levels that seem to make that better than ever. I actually un-did the EQ adjustment that I had rather ineffectively been using since late last year to boost the missing mid-bass after deciding it was causing more harm than good by reducing the available maximum loudness for the Acoustats. Meanwhile, my friend who lives in France who had no stereo set up since moving there bought a pair of Mark Levinson ML-2's, which may be great for his Quad ESL 63's and his Rogers LS3/5a's. We had lots of discussion about that, and the ML-2 is one of the very few Real Class A amplifiers, with most others that call themselves Class A really being amplifiers that are not always Class A but merely deliver rated power in Class A watts into 8 ohms. The ML-2, as a Real Class A amplifier, cannot deliver anything but Class A watts, until the point where it runs out of power supply current with loads below 2 ohms. And we discussed the benefits of regulated power supplies in power amplifiers--Class AB amplifiers would get even more benefit. An ML-2 would not be useful for me on the Acoustats, but I thought for awhile a Mark Levinson No. 20 might be suitable, and is Class A (I thought) and has regulated power. Well it turns out the No. 20 is not a Real Class A amplifier either, though it does generously provide 100 Class A Watts into 8 ohms, and less Class A watts (but more power overall) into lower impedances. It couldn't really be a Real Class A amplifier with 4 times the power on essentially the same chassis as the ML-2. And a full analysis reveals that I need at least as much peak power as the Hafler 9300, which has about 400W peak power into 4 ohms. The No. 20 can only provide 200W power into 4 ohms, and because of the regulated power there is no extra "peak" headroom. So it seems the No. 20 would not be adequate for the Acoustats. I plan to pack and store the Krell for a few years until I have full time to work on it during my retirement. Even the Krell is merely an amp that delivers Class A Watts instead of being Real Class A, but it can ramp up to deliver 400 Class A Watts which is quite a few, and has way more low impedance power than the No 20 amplifier also.
20. Set up an Oyaide power strip in the living room for the existing 2 midrange DACs (permitting ABX switching between two different power amps) and the AES digital splitter that feeds them (which must be on the same AC circuit, I determined last year--though theoretically if the DACs had perfect isolation of the AES inputs as they are supposed to it wouldn't be necessary--for eliminating ground loop hum). Previously and for several years this critical power strip had been a simple plastic Radio Shack variety. That this was still feeding my midrange DACs was an audiophile outrage. A visitor noticed this at the last audio party I hosted in 2017. Anyway, a high end power strip for this is essential because of how critical the DACs are, AND because I'm running the Hafler 9300 which only has single ended inputs. With single ended connections, that makes the low impedance of the ground paths even more important, and The Oyaide does this so much better I feel I can hear the improvement. This tweak helped elevate the Hafler 9300 to the Krell-like level of performance I had previously with balanced connections. All of my other power strips are some kind of audiophile or medical grade...I especially like the $125 Wiremold medical grade power strips which have long 14g cords, no lights or switches, and true medical grade duplex outlets. I use those for all the equipment in the two audio racks on the left side of the room, which are all powered by the power conditioner on the right side of the room from a 20A 10G circuit dedicated to low power devices. But for the DACs only a short cord was needed, and something with even more bling was desireable.
21. Started a new policy of listening to at least one disc or full resolution digital file or stream per night, whether it be a vinyl LP or a plastic disc such as CD or DVD-Audio. Over the years, I've tended not to play discs on work nights, but it takes just a little bit of effort to get a disc playing, and it's worth it for the special good feeling, though I still enjoy FM radio also.
22 & 23. Measured newly purchased refurbished Hafler 9300 and re-measured my original 9300 for comparison. They measured identically, showing that original has not aged and refurb was done correctly. Added measurements to blog post with numbers from the ATI and Parasound amplifiers. Set up the refurbed 9300 on the living room system, and believed it to be the best of all, with more punch than my original 9300 because new capacitors (now "permanent"!). The 9300 beats the ATI and Parasound in noise level and THD+N at the lowest output levels, with the Parasound only pulling slightly ahead monotonically at higher powers (and the ATI catching up with the Parasound after a stall around !w). At 125W all three amplifiers have THD in the 0.00x% range close to my ST 1700B residual.
24. Seeing as my Oppo BDP-95 is providing full high resolution from DVD-Audio discs in two channel at the Coax SPDIF port, I decided for the first time (!) to connect that to my Yamaha receiver. Thankfully I'm beginning to get familiar with Yamaha setup menus, I got this new coax digital input assigned to the input that used to be the Sony DVR now long retired. It sounds wonderful, and enables me to have my normal sub crossover with the disc player (playing discs through the multichannel input, it appears the subwoofer is only activated for "multichannel" modes on multichannel discs, so if you are listening to stereo, you get no subwoofer output at all, which my system relies on, and otherwise sounds very thin. This is an issue with disc playing I'd overlooked for 14 years, now fixed. AND I have a very rare ability to use the high resolution data from high resolution discs, not just 16 bit. AND I can play with all the DSP surround modes, which possibly sound better than discrete multichannel in some ways, probably because of my still unoptimized surround speakers.
26. After setting up the ATI, and struggling to eliminate chassis hum and electrical hum for a few hours, I though it was quiet enough. However, when I played some FM, it sounded surprisingly grainy. I resolved then (without doing anything like a proper test...the FM was a noisier tuner than I usually listen to and even that varies...so there might be nothing wrong with the ATI at all) to put the Parasound 1500A back into the bedroom, and instead use the un-refurbed 9300 I used to use in the living room in the kitchen. The ATI might then be just a spare until I get it refurbed. I put the 1500A back into the bedroom after about 24 hours. However, in the process of trying to make the ATI hum free, I had made some important changes (below).
27. Instead of taking the analog from the Behringer DEQ 2496 for the bedroom power amp, which is problematic because it must be adapted from balanced to unbalanced, and the Behringer has an electrically noisy supply and ground-loop inducing ground connection, I now send the digital from the Behringer to a DAC, a repurposed Denon DVD-5000A which features dual-differential 1704's. The 5000A gets optical digital signal through a high end glass fiber cable, so it is electrically isolated from all the ground loops in the digital processors. That reduced the electrical hum to almost nothing with the ATI. I did this after trying different cables and also adding back in the Harrison Labs attenuators (24dB !) I had removed when originally removing the Parasound. The sound quality was more crystaline clear, but possibly slightly edgy, using the ATI...which was a big motivation to bring back the Parasound as described in item 26. This upgrade had been "planned" for over a year, in fact I had a pair of 5000A's stacked in the bedroom for that long ready to be deployed for the monitors (Revel M20's) and the subwoofer (SVS 1642). However, now that I am using only the 44.1kHz output of the Sonos system, and with only one sampling rate I can use different DAC's, and adjust for the delay difference in the Behringer delay menu. For the time being, I'm still using the analog output of a second Behringer for the subs, and I just guestimated the delay of the 5000A being 10ms and dialed that into the Behringer. It needs to be set properly.
(Not Counted.) I also put the ATI amplifier on an Insteon on/off module so I could turn it off easily when going to sleep, and turn it back on from the bed. I kept that while using the Parasound, but the larger transformer might be an issue with the Insteon module, so I'm manually switching the amplifier for now. I will count this when I've added a proper trigger-generator to turn the amplifier on, powered by Insteon. That gets into issues, as nobody sells a standalone 12V trigger generator. If you use a linear type, as I did in the second bedroom, you must add a calibrated resistor so the voltage drops fast enough not to double click the relay. If you use a digital supply, you must be sure your digital supply does not generate RFI into the air and back into the powerline, otherwise corrupt the whole audio system. Rod Elliot discusses the design of proper audio system trigger relays and generators. You will see his trigger generator schematic shows 22 parts including 10 semiconductors! And that's with a simple linear supply.
http://sound.whsites.net/project156.htm
If you think I'm paranoid about RFI from small DC supplies, read this discussion of linear vs switched supplies by a ham.
http://ka7oei.blogspot.com/2014/08/completely-containing-switching-power.html
28. Also to reduce hum, I first found how to plug the behringer into the same duplex outlet on the Brickwall surge filter I use in the bedroom. That helped a little, and when I started using the 5000A, I also plugged it into the same duplex outlet as the amplifier.
29. Reaching the end of the month, I was cleaning the living room and came across the warranty card and interconnect that came with the SSI surround processor 1000 II. That was one of only two required cables to set up my new surround back for DVD-Audio's (which don't have discrete back surround) with 3 choices on a selector switch: (1) discrete--straight from the Oppo surround back jacks, which are inoperative with DVD-Audio and SACD but operative with AIX Blu Ray, (2) Simulated back using the processor, using the processor's "surround" channels as the new back channels, and (3) duplicated from the surround channels, which might work best in some cases, and is mandated for ambisonic and ambiphonic (with disconnected surround sides...I decided not to bother with a external switch for that...though I have a new chifi switch on order.
Actually, the night before, also clearing the Living Room, I opened the box for the new custom Y cables from ProAudioLA.com. These connect the side "surround" outputs to the Yahama side surround inputs AND the processor "front channel" inputs. It took some thinking to get this connected correctly. And I needed to re-power the Oppo, which had been disconnected from the power strip to make room for the new front channel amplifier which is not fully hooked up yet, but I've determined that it doesn't pollute the AC ground at all, turned off or not, so no ground loop problem. That's my original Hafler 9300 I used to use in the living room.
Put on Hotel California in 5.1, playing surround side and back channels only. It was clearly better to have surround back simulated than none from the disc. The processed seemed better than the duplicated, and I fiddled with the controls to make it sound even better.
Tada! Surround is now sounding...fun, and really fun for the first time. Stereo may still have more soul, however, I haven't changed my observation on that yet.
This might even be better than full 7.1 discrete, because you can customize it, I am thinking now.
(Not counted.) Replaced the Mapleshade weights on top of the cover of the new living room 9300, which is a trifle loose. It required a slightly different positioning. Not counted because I had these on the previous unit.
1. Hung right surround speaker on wall for the first time in 14 years since since I got the speakers. Previously it had been sitting on the equipment rack right to my side, hardly surround at all. I made a goal of doing this in January, and just barely pulled it off. I find it hard to hang things on walls, but I believe I did a great job with two stud-mounted screws for the speaker mount. I ultimately came up with a wiring scheme in which the teflon coated silver plated 14g wire is twisted loosely around the ball of the clamp, so when unscrewing it, hopefully at least, it doesn't fall to the floor.
2 Did 2 generations of Needle Drop experiments on the Stereo Review Test Record 12 on my LP12 based turntable. (After getting the record cleaned by a gracious audiophile friend on his Loricraft Record Cleaner.) From the first generation, a friend determined among other things the horizontal and vertical arm/cartridge resonances were 13+ Hz, much too high. Also the horizontal low frequency resonance is disturbingly undamped.
3. I applied cloth Hockey Tape to the Ittok tonearm and integral headshell to increase mass (to lower the arm/cartridge resonant frequency) AND to dampen the transmission resonances of the much much too resonant undamped stainless Ittok arm. This resonance improvement was spectacular, and in combination with the clamp I use have elevated my Vinyl Playback to Best Ever For Me, exceeding in almost all ways the sound of my PSX-800 rig (which may actually have been noticeably more speed stable...but otherwise similar sounding) also helped by the best preamp I've ever had by far (the Emotiva XSP-1) and the best speakers and tuning, etc. Additional tests continue to show the superiority of clamping vs not clamping. I believe the common audiophile notion that you can have too much damping is almost completely wrong, and the Linn notion that you want zero damping is total nonsense. The more complete damping the better, and that is the approach followed by all the megabuck turntable systems of the past couple decades (except Linn). My friend in France discovered Hockey Tape as an ideal damping material for turntable parts many years ago also applied his knowledge to the record cutting system of a famous mastering engineer, leading to a Grammy winning recording.
4. The second generation of Needle drop showed the vertical resonance had dropped by 1 Hz, but the lateral resonance only 0.5 Hz, because the arm's lateral mass is about twice as much as vertical, which is easy to imagine, the entire central base of the arm pivots only in on the horizontal axis. (At least another coat of Hockey Tape is desirable at this point, to reduce mass another Hz. Maybe two more coats. And, an extra dose, possibly combined with coins, application to the horizontal top bar of the pivot (which doesn't move except laterally) in order to give an extra mass boost to lower the frequency of the horizontal resonance.)
5. Determined that all 4 (Optimus) RCA LX-55 surrounds speakers sounded best with the speaker ports completely stuffed. I did this stuffing using folded dark grey foam backing rod, which looks cool I think, and could easily be removed. The bass needs as much reduction as possible, even with the Small speaker setting (and permitted by it as well, because of the near ceiling positioning of the speakers, which is unavoidable in the kitchen.
(Not Counted.) I damaged one LX55 speaker in the process, and replaced it with my final #5 unit, which I had to dig out of storage. The damaged speaker had very brittle woofer surround, and the pliers I was trying to use to remove the final straw that had been in the port but fell inside, I barely touched the foam surround and it cut like beer foam, and there was no going back. Now the damaged speaker is in the workshop for testing with my two varieties of replacement woofer I obtained, as I was planning to do anyway for all the speakers eventually, once I've determined the best replacement and modification strategy. One of the replacement varieties I obtained is Italian made and actually has flat response to 5kHz, where most 5" woofers have a serious dustcap resonance peak there. I found out about both by read ing LX-5 replacement stories online. My LX-55's are virtually identical to the original Optimus LX-5's, I think, but so LX-55's were sold you can't find out much about them. I bought an additional NOS LX-55 online for comparison and experimentation and I ultimately plan on have 6 surround speakers anyway.
(Not Counted.) Also for future surround speaker experimentation, I obtained a pair of the famous Infinity "Walsh Tweeters" (not really a Walsh driver, as those most face downwards into a box load, but these Infinity drivers are famous and special in their own right). These are normally crossed over at 10kHz on the actual RS-2000 Infinity Monitors (which was possibly the first speaker I fell in love with, or lust, sometime around 1971), as I finally determined after finally being inspired to buy the tweeters, from a well known refurbisher on eBay. (He packed them AMAZINGLY well, every detail of packaging optimized.) So I know own the most exotic part (and actually the only part I find even remotely interesting now) from the first speaker I fell in love with. I also determined that in the original loudspeaker, they are crossed over with a simple capacitor. It's possible with a steeper crossover, and for low power surround speaker use, they could be crossed as low as 6kHz, which would make a perfectly omnidirectional system out of the LX-55 woofer after removing the problematic Radio Shack "Lineaum" tweeter (which, actually, I don't have very much respect for anymore, it's full of suckouts below 10kHz and there is virtually nothing above 10kHz). This is currently my "ultimate" idea for surround speaker (small woofer plus magical omni tweeter), but I'm not sure I'll get to it this year. Lots of testing will be needed, including to determine how far down the tweeter can play well, and this needs to be done with utmost care.
6 & 7. (6) Determined that the previous anti-skate level on my Linn turntable was inadequate, in several ways, including my usual blank disc, and a new full sided blank disc. In the final adjustment, I set the Ittok anti-skate to maximum, a reading of about 3.2. This produces stasis at all parts of the blank record...sometimes there is a back and forth but the arm never gets carried away inward as it does at lower anti-skate settings. My actual tracking force is around 2.2g. This new anti-skate setting is no doubt also part of the best sound ever. Also, it almost completely eliminates the problem of the cartridge going haywire, as it was ALWAYS doing, at the center of records. I now observed that (7) to be the side of the wide Dynavector 17D3 cartridge body hitting the clamp and bouncing slightly back away from the center, over and over. But, with the better anti-skate compensation, the cartridge body is better centered and therefore further inwards relative to the stylus, as it should be, and doesn't hit the clamp. This is great for playing most records now, but sadly it still doesn't work on all records. I could possibly benefit from an arm lifting device like Q Up.
8. I cleared the old VCR player and stack of recordings and stuff 18 inches high from atop the kitchen rack away. This means I can actually see the wall attached right surround speaker more clearly, and improves the sound greatly (it was very very dark sounding before, and of course I couldn't even see it). I also twisted the speaker more downward because the high frequences are very reduced below the axis of the speaker. So now it is pointed 35 degrees or so toward the listening position. This improved the darkness, but it may still be the most dark sounding of all the speakers, but it's also hard to tell fairly. But clearly the Audiogeorge modified units, with tweeter phase made uninverted and woofer choke removed, sound desirably brighter, I have guessed, reversing my previous opinions. I think this is primarily because of the boundar positioning. I plan to remove the right surround speaker from the wall mount, test the tweeter better, try reversing the tweeter phase, as a first step. I also have a brand new (NOS) speaker unit to compare it to, and the damaged woofer unit. The VCR has moved underneath the kitchen table where it will be part of a table rack I made years ago along with whatever I use as the Kichen Front amplifier, and possible the surround amplifier too (which would probably be the Yamaha receiver when I get a new processor).
9. I have positioned a new-to-me surround processing unit atop the rack, but pushed far back, and the unit is quite low, for a special kind of surround processing (not the usual modern processor stuff, but more on that later) that merely expands 5.1 recordings to 7.1 speakers so I can enjoy all my surround speakers with music 5.1 recordings. The "New" unit is a NOS SSI System 1000 II stereo processor. It is intended for generating 5.1 channels from 2, a mid 1980's early surround processor. It proclaims Dolby Surround, and this is nearly the first implementation. Basically it uses a Hafler-like matrix to produce the side surrounds, combined with a bucket brigade delay system that uses Dolby noise reduction. I'm unclear if the noise reduction is use double ended (to reduce the noise from the early bucket-brigade delay) or single ended, to soften the sound of the back. Anyway, my idea is to use this processor on the OPPO side surrounds as if they were the front speakers, and then take the "surround" produced by the processor for the back surround speakers, thereby expanding a 5.1 signal as on all DVD's into a 7.1 signal for my 7.1 speaker arrangement. I read someone suggesting an idea like this. Also it's possible simply to duplicate the sides for the backs (side surrounds and back surrounds playing the "side surround" signal). I'm going to set up a switch (already in place) to select 1. derived back surround speakers as I just described using the SSI processor, 2. duplicated signal for the back surrounds from the side surround signal, 3. routing the sides TO the backs alone for ambisonic and ambiphonic recordings, of which I have a few, and 4. actual discrete 7.1 which the Oppo produces from some Blu Ray discs, such as the AIX Blu Ray sampler I have.
(Not Counted.) I have also read a lot of reviews and other information on more modern Surround Sound processors. Unlike anything I've had, now multichannel audio input is now handled through HDMI, and many units come with advanced room correction. I'd like to have at least Audyssey XT32, and also some kind of loudness eq system like Audyssey Dynamic Volume and EQ. And of course some way of generating 7.1 and at least 9.1 systems (including front wides) from 5.1 sources. I've come close to buying a few models like this on eBay, and also from an audiphile friend, but I'm in no hurry, as I want to get the speakers and other things optimized first, and I look forward to playing with my home brew 5.1 to 7.1 conversion--which provides many direct adjustments perhaps unavailable on modern processors. I also checked out the features of my Integra Research RDC7, obtaining the actual manual for my "Upgraded" unit. It does have analog multichannel inputs (only) and you have to use a custom snake cable to connect them through a DB25 connector. Not only does it not have 7.1 inputs (which even my Yamaha does), it appears not to have precisely Dolby Pro Logic IIx (only II), however what it is similarly able to derive 7.1 channels from 5.1 sources. I was long planning to use RDC7 as my "ultimate" surround processor but I now understand the important features it doesn't have, like HDMI inputs, 7.1 input channels, and ultimately I do want to have at least a 9.1 setup with wide channels.
10. FINALLY (after 4 years of chipping away on this project) I re-established the Queen's Room (guest bedroom) stereo, with Tripplite power strip horizontally mounted inside the desk underneath shelf with 8 outlets. The small amplifier is started with a trigger voltage generator: a 12V DC linear type power supply wall-wart, feeding a silicone wrapped bleed-off resistor calibrated to provide shut-off in about a second. That is switched by an Insteon Home Control On-Off module, which I have programmed my Universal Devices controller to be controlled by the Insteon On-Off wall switch which controls the light and fan. Once the light is turned on, and you wait 2 seconds, you just tap the light switch a second time and the stereo (featuring a tiny Parasound amp and the Gallo A'Diva speakers) comes on, with audio signal from a Sonos Connect, which is set up to play the FM tuner from another room, the Pioneer F-26 which is tuned to KPAC-FM, the all classical radio station. Then, when you turn the lights off, the stereo also switches off. This is great for visits and my girl friend loved it when I demonstrated it last week. I didn't mention that I had many other ideas, so you could also play the stereo when the lights were off and turn the stereo on and off without turning the lights on or off. But I decided not to make it any more complicated right away. Now, it's very simple, and she likes that. This was also a major home improvement project. The longest delay was determining the proper resistor size. I waited until a computer club meeting to do that. I found the bleed resistor testing interesting but my friend thought it was a waste to use a linear wall wart when a switching type would simply drop the voltage immediately, problem solved. I felt a switching wall wart would corrupt the AC power on the power strip and degrade the audio quality. He thought that concern was silly. But I went ahead and did it my way, finally with full silicon sealing on the bleed resistor. Then it took another year to get around to ordering the power strip AND especially drilling the holes in the cabinet and mounting the new power strip to it, which required another trip to the hardware store to get long enough screws than Tripplite had provided. Despite all the added complexity, the wiring of the setup is much tidier now thanks to the horizontally mounted power strip.
11. Got Roon Set Up. This was big for me, I always wanted Roon, but with my 8 zone Sonos system, I was hardly about to switch to these new fancy streaming systems costing $2k-$20k Per Node. Perhaps, I opinied, I one day when I had lots of time I would set up a Raspberry Pi system with an audio network similar to Sonos in which I could run Roon (see Roon Raspberry Pi). But in Feburary a friend told me that Roon now supports Sonos. Hurrah!!! Before long I installed Roon on my main kitchen Macintosh. Now I can run Roon on my Sonos system, and it works great. Finally it is easy to use Tidal, and know what kind of version you are playing. Generally, I would prefer the plain vanilla PCM I think, but since the Roon/Tidal/Sonos system finally at least does some level of "unfolding" automatically, having MQA is not so much a loss. Maybe it would be a gain in some cases? Anyway, I'm happy that I now have the system I dreamed of having in these regards. I'm getting used to Roon. I hope they continue to imrpove it, and personally, if they do keep improving it, I'm happy paying an annual charge.
12. Bought, tested, and set up an ATI 1502 amplifier in the bedroom now but basically because I wanted a new amplifier for he Revel M20's in the kitchen--where I may ultimately put either the ATI or the Parasound HCA-1500A. I had long been interested in ATI amplifiers, but mostly lusting after newer TOTL signature models. A friend pointed out a Parasound HCA-1500A as I already had in the bedroom would probably be better for the kitchen as well. Anyway, I bought an ATI 1502, one of the earliest ATI models, something I almost bought about 15 years ago at a friend-of-a-friends house. I think it's beautifully made on the outside, looks better made than a piece of General Radio equipment, and I love the big side fins. I did measurements on two days, (the first day of measurements being all in error for reasons I'm unclear of but I know to avoid doing certain things on my ST1700B), showing both to be excellent amplifiers in power, noise level, and THD+N (all the things I can measure on ST1700B and a scope, I didn't have time for other measurements). Amazingly the ATI 1502 is better than the 1500A on static noise level, but in most distortion measurements the 1500A is very slightly better. Overall, but based only on these limited measurements that didn't include distortion and noise spectra and damping-factor-by-frequency, I doubt I'd be able to hear a difference between the amplifiers, and I doubt there's significant difference in the unmeasured areas as well. By choice I'd take the Parasound due to trigger switch and lower distortion, but the ATI may yet have some advantages, we'll see. The one I received is very nice --it looks exactly like the one I passed up on 15 years ago as if it were stored in a museum since then.. And it was packed beautifully with foam-in-place as if it was General Radio equipment too. One can't count on those aspects of an equipment purchase, so it's a happy purchase despite seeing an HCA-1500A on ebay for $499 right after I bought the ATI, and given choice between the two I might take the Parasound. For awhile I considered the additional HCA-1500A also, but then decided to buy an "upgraded" Hafler 9300 with new increased capacitance, which is hard to do in the small chassis. It might be better than my main 9300, we'll see. If nothing else I'll see if new capacitors makes a difference (I've been thinking my Hafler slightly power supply weak, just doesn't have quite the "kick" of the Krell, though it may sound better than the Krell otherwise). The ATI is now set up in the bedroom partly as experiment, but I've decided it makes slightly too much chassis sound and directs it better into the room than the parasound, so I have it turned off, and I'm seeing if my cat tolerates the lack of a warm amplifier next to where he sleeps. I think the Parasound made about as much chassis noise, but it was directed more diffusely so I couldn't tell where it came from. Now I know from experiment this quarter that most of the background hum comes from the power amplfier, and it's something worth fixing somehow. I could have an automated switch to turn the amp on and off, and/or I could refurbish the power supply capacitors in the amplifier. All this amplifier stuff (the new 9300 has just arrived, waiting to be tested) and I haven't gotten around to...well the miniDSP's for one thing. Though I did find this quarter I could run the major linear phase EQ program using Wine on my Mac, at least for now as long as I stick with less than Mojave OS. In Mojave they remove support for 32 bit applications, and last I checked Wine was still catching up with that, however they said they would ultimately support even 32 bit windows applications on Mohave.
13. I added a heat shield to protect my 4x4 video matrix switched (used by my household video network, from 4 kitchen based sources) from the heat from my Yamaha HTR-5970 receiver. It gets plenty hot, even hotter playing mutichannel, with the bottom of the matrix switch getting ominously hot. Not only did this require figuring out how to do this (I had many other plans, and at one point tried aluminum foil, but that was ridiculous) and getting the rack brackets, then rack screws, then labeling and removing enough connections (a lot!!!) to get the paper foamboard squeezed in--and it is very tightly squeezed in and feels about as hard as wood--it would be impossible for it to just fall. Now, not only does the matrix switch stay cool, it almost seems like the Yahama is staying slightly cooler. But I really need to off-load the excess load of the 6 ohm Revel M20 main speakers from the Yamaha. That was the justification for buying the ATI amplifier, though now I might run the ATI in the bedroom, or maybe not.
14. I set up a stepped attenuator to attenuate the Mac computer audio output being input to my Pioneer video recorder. It needs to be reduced because the output of the Schiit converter which feeds the recorder inputs (I use that after a series of digital splitters sends off the digtal to the receiver also) is 2V, and the video recorder inputs expect 1V. Formerly I had some Harrison Labs attenuators, but those aren't necessarily the greatest, and I misplaced them.
15. I performed a series of changes reduced the kitchen system hum level often to as low as -150dB as seen from the Subwoofer EQ now installed in the main rack. I tried lots of things, the ultimate so far was to feed the source signal from the Yahama receiver with a solid ground connection to the Behringer EQ, which is basically the only thing in the system (now) which is actually grounded. I had been isolating that the EQ with an isolation transformer, but it turned out that had been making the ground loop hum worse. I also came up with how to handle other grounds, the FM from the outside antenna which already goes through a high end arrestor outside is now grounded inside to my auxiliary power strip plugged straight into the wall (a Monster) and then isolated with an FM/RF isolation transformer before going into the tuner. Before all these changes, which I think I started in January, the hum was pushing -90dB. Even now it occasionally rises to -135db and I don't know why, but that is far better than -90dB.
16. I have upgraded the Oppo BDP-95 with the latest firmware (over the net, it was a piece of cake) so it now plays up to 7.1 channels on Blu Ray discs which have 7.1 channels. (Apparently all DVD's, even DVD-Audio, only has 5.1 channels.) I first discovered and had to prove that I was not getting all seven channels from the oppo. I could tell the test tone didn't do that, but I figured the error was limited to the test tones and when actually playing 7.1 channel discs you would get them all (including the essential back surround channels). But even after I acquired the AIX Records calibration disc on ebay, I still found the back channels weren't working and confirmed that on a voltmeter. It was also a question of whether the inputs--which require menu programming thats somewhat complex--were actually send all 7.1 channels through the Yahama. It really only has 5.1 input jacks, but if you program some mode you can use another input as the front channels, then you get the back channel inputs where the old fronts used to be. It took some effort, even getting the Yamaha menus to work on the Yamaha remote which I finally did too, to get this to work. But I ultimately verified I was not getting the backs out of the Yamaha using the AIX disc and a voltmeter connected to the outputs so there was no uncertainty. So then I also checked if I was getting up to 96kHz and 24 bits from the Oppo SPDIF digital output. I confirmed that it was doing that using DVD-Audio discs (but not Blu Ray) and the Sencore digital analyzer, which can show the active number of bits too (I was thinking I needed to make a recording and use analyzer software for that, but the Sencore did it directly on the digital signal). So then after upgrading the Oppo both the Test Tone AND the 7.1 output from the AIX blu ray worked. And I was still getting at least up to 96kHz and 24 bits from the digital outputs, though of course with the copy protect bit set so no digital recorders will record the signal (just as it had been before, and I know now for sure I never made a direct digital recording of a DVD-Audio, though I often thought I could, I merely made different analog samplings). Oppo always gave the consumer user the most possible, pushing the envelope of what they could get away with under the noses of the DRM people at movie studios. Even after upgrading, I was also still able to insert and run the Region Free ISO disc just enough to makes my BDP-95 Region Free and I can play may Blakes Seven movies on it. So all my fears about upgrading the Oppo had been unwarranted--I lost nothing--and I gained the full 7.1 outputs from the Blu Ray discs that have them.
17. I performed numerous measurements and adjustments to the Kitchen surround speaker level and delay controls and subwoofer level and EQ adjustments on the Behringer EQ now added for the subwoofer (I can't remember when I hooked up the EQ, that may have been in this Quarter also). Finally I concluded it's best to set the level controls ONLY in the Yamaha, and set the delay controls in both, because the multichannel inputs DO get level control in the Yamaha, but the delay and EQ don't apply to the multichannel inuts. I added but ultimately removed EQ's from the surround speakers themselves partly since I can't use it when playing multichannel discs through my Yamaha anyway (the multichannel input on the Yamaha does no digital conversion or EQ or delay processiong, however it does apply the relative level adjustments) and I want to focus on fixing the unEQ'd response of the speakers first. I've also done lots more listening to surround processing modes on the Yamaha (for 2 channel sources) and multichannel discs than I've ever done before.
18. Visited an audiophile friend, and determined that his system DID reproduce midbass that my living room system is lacking, which I measured and figured was caused by reflection cancellation last year. I determined this by listening to a female vocalist. It turned out that he had a similar cancellation, which he fixed using a different miniDSP model from what I got. He fed a REW-calculated midbass adjustment through that as a different channel into his pair of subwoofers. I had been thinking of doing a similar thing, in various ways. What an inspiration!
19. Measured the damping factor of the Krell using several frequencies and loads and reported to this blog. That was the only thing I've done on the Krell this year...I've switched to playing on the Hafler 9300, and made some minor adjustments to EQ's and levels that seem to make that better than ever. I actually un-did the EQ adjustment that I had rather ineffectively been using since late last year to boost the missing mid-bass after deciding it was causing more harm than good by reducing the available maximum loudness for the Acoustats. Meanwhile, my friend who lives in France who had no stereo set up since moving there bought a pair of Mark Levinson ML-2's, which may be great for his Quad ESL 63's and his Rogers LS3/5a's. We had lots of discussion about that, and the ML-2 is one of the very few Real Class A amplifiers, with most others that call themselves Class A really being amplifiers that are not always Class A but merely deliver rated power in Class A watts into 8 ohms. The ML-2, as a Real Class A amplifier, cannot deliver anything but Class A watts, until the point where it runs out of power supply current with loads below 2 ohms. And we discussed the benefits of regulated power supplies in power amplifiers--Class AB amplifiers would get even more benefit. An ML-2 would not be useful for me on the Acoustats, but I thought for awhile a Mark Levinson No. 20 might be suitable, and is Class A (I thought) and has regulated power. Well it turns out the No. 20 is not a Real Class A amplifier either, though it does generously provide 100 Class A Watts into 8 ohms, and less Class A watts (but more power overall) into lower impedances. It couldn't really be a Real Class A amplifier with 4 times the power on essentially the same chassis as the ML-2. And a full analysis reveals that I need at least as much peak power as the Hafler 9300, which has about 400W peak power into 4 ohms. The No. 20 can only provide 200W power into 4 ohms, and because of the regulated power there is no extra "peak" headroom. So it seems the No. 20 would not be adequate for the Acoustats. I plan to pack and store the Krell for a few years until I have full time to work on it during my retirement. Even the Krell is merely an amp that delivers Class A Watts instead of being Real Class A, but it can ramp up to deliver 400 Class A Watts which is quite a few, and has way more low impedance power than the No 20 amplifier also.
20. Set up an Oyaide power strip in the living room for the existing 2 midrange DACs (permitting ABX switching between two different power amps) and the AES digital splitter that feeds them (which must be on the same AC circuit, I determined last year--though theoretically if the DACs had perfect isolation of the AES inputs as they are supposed to it wouldn't be necessary--for eliminating ground loop hum). Previously and for several years this critical power strip had been a simple plastic Radio Shack variety. That this was still feeding my midrange DACs was an audiophile outrage. A visitor noticed this at the last audio party I hosted in 2017. Anyway, a high end power strip for this is essential because of how critical the DACs are, AND because I'm running the Hafler 9300 which only has single ended inputs. With single ended connections, that makes the low impedance of the ground paths even more important, and The Oyaide does this so much better I feel I can hear the improvement. This tweak helped elevate the Hafler 9300 to the Krell-like level of performance I had previously with balanced connections. All of my other power strips are some kind of audiophile or medical grade...I especially like the $125 Wiremold medical grade power strips which have long 14g cords, no lights or switches, and true medical grade duplex outlets. I use those for all the equipment in the two audio racks on the left side of the room, which are all powered by the power conditioner on the right side of the room from a 20A 10G circuit dedicated to low power devices. But for the DACs only a short cord was needed, and something with even more bling was desireable.
21. Started a new policy of listening to at least one disc or full resolution digital file or stream per night, whether it be a vinyl LP or a plastic disc such as CD or DVD-Audio. Over the years, I've tended not to play discs on work nights, but it takes just a little bit of effort to get a disc playing, and it's worth it for the special good feeling, though I still enjoy FM radio also.
22 & 23. Measured newly purchased refurbished Hafler 9300 and re-measured my original 9300 for comparison. They measured identically, showing that original has not aged and refurb was done correctly. Added measurements to blog post with numbers from the ATI and Parasound amplifiers. Set up the refurbed 9300 on the living room system, and believed it to be the best of all, with more punch than my original 9300 because new capacitors (now "permanent"!). The 9300 beats the ATI and Parasound in noise level and THD+N at the lowest output levels, with the Parasound only pulling slightly ahead monotonically at higher powers (and the ATI catching up with the Parasound after a stall around !w). At 125W all three amplifiers have THD in the 0.00x% range close to my ST 1700B residual.
24. Seeing as my Oppo BDP-95 is providing full high resolution from DVD-Audio discs in two channel at the Coax SPDIF port, I decided for the first time (!) to connect that to my Yamaha receiver. Thankfully I'm beginning to get familiar with Yamaha setup menus, I got this new coax digital input assigned to the input that used to be the Sony DVR now long retired. It sounds wonderful, and enables me to have my normal sub crossover with the disc player (playing discs through the multichannel input, it appears the subwoofer is only activated for "multichannel" modes on multichannel discs, so if you are listening to stereo, you get no subwoofer output at all, which my system relies on, and otherwise sounds very thin. This is an issue with disc playing I'd overlooked for 14 years, now fixed. AND I have a very rare ability to use the high resolution data from high resolution discs, not just 16 bit. AND I can play with all the DSP surround modes, which possibly sound better than discrete multichannel in some ways, probably because of my still unoptimized surround speakers.
26. After setting up the ATI, and struggling to eliminate chassis hum and electrical hum for a few hours, I though it was quiet enough. However, when I played some FM, it sounded surprisingly grainy. I resolved then (without doing anything like a proper test...the FM was a noisier tuner than I usually listen to and even that varies...so there might be nothing wrong with the ATI at all) to put the Parasound 1500A back into the bedroom, and instead use the un-refurbed 9300 I used to use in the living room in the kitchen. The ATI might then be just a spare until I get it refurbed. I put the 1500A back into the bedroom after about 24 hours. However, in the process of trying to make the ATI hum free, I had made some important changes (below).
27. Instead of taking the analog from the Behringer DEQ 2496 for the bedroom power amp, which is problematic because it must be adapted from balanced to unbalanced, and the Behringer has an electrically noisy supply and ground-loop inducing ground connection, I now send the digital from the Behringer to a DAC, a repurposed Denon DVD-5000A which features dual-differential 1704's. The 5000A gets optical digital signal through a high end glass fiber cable, so it is electrically isolated from all the ground loops in the digital processors. That reduced the electrical hum to almost nothing with the ATI. I did this after trying different cables and also adding back in the Harrison Labs attenuators (24dB !) I had removed when originally removing the Parasound. The sound quality was more crystaline clear, but possibly slightly edgy, using the ATI...which was a big motivation to bring back the Parasound as described in item 26. This upgrade had been "planned" for over a year, in fact I had a pair of 5000A's stacked in the bedroom for that long ready to be deployed for the monitors (Revel M20's) and the subwoofer (SVS 1642). However, now that I am using only the 44.1kHz output of the Sonos system, and with only one sampling rate I can use different DAC's, and adjust for the delay difference in the Behringer delay menu. For the time being, I'm still using the analog output of a second Behringer for the subs, and I just guestimated the delay of the 5000A being 10ms and dialed that into the Behringer. It needs to be set properly.
(Not Counted.) I also put the ATI amplifier on an Insteon on/off module so I could turn it off easily when going to sleep, and turn it back on from the bed. I kept that while using the Parasound, but the larger transformer might be an issue with the Insteon module, so I'm manually switching the amplifier for now. I will count this when I've added a proper trigger-generator to turn the amplifier on, powered by Insteon. That gets into issues, as nobody sells a standalone 12V trigger generator. If you use a linear type, as I did in the second bedroom, you must add a calibrated resistor so the voltage drops fast enough not to double click the relay. If you use a digital supply, you must be sure your digital supply does not generate RFI into the air and back into the powerline, otherwise corrupt the whole audio system. Rod Elliot discusses the design of proper audio system trigger relays and generators. You will see his trigger generator schematic shows 22 parts including 10 semiconductors! And that's with a simple linear supply.
http://sound.whsites.net/project156.htm
If you think I'm paranoid about RFI from small DC supplies, read this discussion of linear vs switched supplies by a ham.
http://ka7oei.blogspot.com/2014/08/completely-containing-switching-power.html
28. Also to reduce hum, I first found how to plug the behringer into the same duplex outlet on the Brickwall surge filter I use in the bedroom. That helped a little, and when I started using the 5000A, I also plugged it into the same duplex outlet as the amplifier.
29. Reaching the end of the month, I was cleaning the living room and came across the warranty card and interconnect that came with the SSI surround processor 1000 II. That was one of only two required cables to set up my new surround back for DVD-Audio's (which don't have discrete back surround) with 3 choices on a selector switch: (1) discrete--straight from the Oppo surround back jacks, which are inoperative with DVD-Audio and SACD but operative with AIX Blu Ray, (2) Simulated back using the processor, using the processor's "surround" channels as the new back channels, and (3) duplicated from the surround channels, which might work best in some cases, and is mandated for ambisonic and ambiphonic (with disconnected surround sides...I decided not to bother with a external switch for that...though I have a new chifi switch on order.
Actually, the night before, also clearing the Living Room, I opened the box for the new custom Y cables from ProAudioLA.com. These connect the side "surround" outputs to the Yahama side surround inputs AND the processor "front channel" inputs. It took some thinking to get this connected correctly. And I needed to re-power the Oppo, which had been disconnected from the power strip to make room for the new front channel amplifier which is not fully hooked up yet, but I've determined that it doesn't pollute the AC ground at all, turned off or not, so no ground loop problem. That's my original Hafler 9300 I used to use in the living room.
Put on Hotel California in 5.1, playing surround side and back channels only. It was clearly better to have surround back simulated than none from the disc. The processed seemed better than the duplicated, and I fiddled with the controls to make it sound even better.
Tada! Surround is now sounding...fun, and really fun for the first time. Stereo may still have more soul, however, I haven't changed my observation on that yet.
This might even be better than full 7.1 discrete, because you can customize it, I am thinking now.
(Not counted.) Replaced the Mapleshade weights on top of the cover of the new living room 9300, which is a trifle loose. It required a slightly different positioning. Not counted because I had these on the previous unit.
