Monday, January 4, 2021

2020: Biggest Year for Audio Improvements Yet

 It was not a good year in many ways because of COVID-19.  I especially missed hearing the San Antonio Symphony after February 2020.  Fortunately, so far, all of my close friends and associates and I are still in good health, and staying as safe as possible.

But for improvements to my audio system, it was probably the best year yet.  Major improvements included:

1) The Semi-Automatic Music System (SAMS--a long post about this is currently being written) was implemented.  I had been thinking about something like this for over 4 decades if not 5.  This is the integration of my Home Automation system (based on Insteon and Universal Devices) with my living room stereo.  From 5 keypads around the house, I can turn on Background Music (an FM tuner set to the wonderful classical radio station KPAC), Mute, or enable Feature Music (everything else).  When I hit the sack for sleep at night or a nap in the afternoon, I press the Bedtime button on my bedside keypad and the stereo shuts off.  So now I can very easily enjoy the classical FM station every day, all day long, with little effort.  Previously I could go days without even turning the stereo on, partly because doing so was such a big hassle.  Unlike some of my dreams, it doesn't automatically read my mood and select music, nor does it even automatically turn on (except after a Mute that hasn't been made Mute Hold), but nevertheless it has quickly made a big change in my lifestyle.  I now can and mostly do have music playing every waking hour, and almost every waking minute, since I only need to shut it off the second I hit the sack.  Audiophiles generally don't seem to be interested in such things, but I think it's very important and I will continue making it better.  Although I have long been and remain a "good stereo in every room in the house" kind of person, the living room system very nicely distributes background music through the house, all the better much of the time for not being "in your face."

None of this requires an app.  It does not require logging into a smartphone first.  It's simple pushbuttons in wall and table keypads.  No menus or popups.  I hate things that require apps to enable.  For one thing, it's not reflexive, unless you're a phone addict who never lets go of it.  For my "ambient light" home program, I have a very cool ceiling projector that can only be operated by push buttons.  But the manufacturer isn't interested in DC trigger control, only app control.  Everyone wants you to use their apps.  It fits into the planned obsolescence modern computing monopoly bundled "services," advertisement, and spyware model, not the independent audiophile and DIY mindset.  Computing apps and services fold in years, good audio equipment remains wonderful for decades.  Contact closures and DC triggers are open system ways of controlling things that move from one "system" to another eternally.  I still haven't recovered from when Sonos de-certified their CR100 dedicated controllers with no replacement except an app.   The CR100 was always there at my bedside, always a touch away from carrying out some function (until the later days when they were frequently making updates).  It wasn't much a vehicle for advertising (though I'm not sure about spyware...I didn't read the fine print) so that meant it had to go with no replacement.  Apps are fine, great indeed, for adjusting things, like the new app for my SVS subwoofer.  Apps are not great for turning on or off the stereo.  Apps require too much work for something that needs to be simple and reflexive.  But everyone want you to be hooked into their stereo ecosystem, through their app.  So, of course, you'll buy more stuff from them, and not anyone else.  So they avoid universal and compatible solutions such as contact closure and/or DC triggers, and boast about their wonderful apps to run all the things in our lives, or at least one of them--with other apps for each of the others.

2) Linear Phase Crossovers were rolled out.  I first heard about linear phase crossovers decades ago--from Siegfried Linkwitz himself!  (He chose not to go this route.)   This is my first ever attempt to do this, and it sounds great.  Greatly improves transparency and reduces excess bass overhang.

3) Steep Crossovers were rolled out.  I did this just before the Linear Phase crossovers, and it might have even been more important than the latter.  It made a huge and obvious difference, as well as enabling me to play louder without various Acoustat and Subwoofer artifacts.  I went from LR4 crossovers to LR8, ie from 24dB per octave to 48dB per octave.

4) Both the Linear Phase and Steep Crossover improvements were made possible by putting 3 miniDSP OpenDRC processors in line with my 3 "ways" (sub, panel, supertweeters).  Meanwhile I did not give up the still useful Behringer DEQ's, thanks to AES digital interfaces, there is no loss having more digital processors in line.  I first purchased these miniDSP's over 2 years ago but never had the time to set them up and program them.

5) Living room FM tuner is now connected to an outdoor antenna.  I had two outdoor whip antennas installed in 2017, and immediately put one to use with my Kitchen FM tuner, which is handy to tune different stations on.  However I did not connect the second whip antenna to the living room FM tuner until just a few months ago.  I had intended the second whip for my Scanner, which I finally got around to buying in 2020.  But comparing kitchen and living room tuners...the living room sounded good but was quite a bit noisier...I decided to repurpose the second whip antenna slightly.  After trying two different FM Separators, I finally settled on a 2 Way Splitter to split the antenna signal between the FM tuner and the Scanner.  On the tuner, it seems to make almost no difference as compared with no splitter.  In fact in my first and only test, the FM seemed to sound better going through the splitter.

The lowered noise level was only one of the improvements this made in the sound.  It's far nicer sounding, more transparent (almost like uncompressed digital recordings) and a continual bass rumble has mostly gone away.  That was the bass rumble which sometimes caused my Krell to shut down, when I was still using the Krell.

The SAMS would have been pointless without the improvements in sound from the living room FM tuner.  I couldn't bear to keep KPAC turned on all day before this.

6) Speaker wiring improved.  Nearly all speaker wires are now hand-twisted silver plated 14g copper with PTFE insulation.  I picked up a roll of this milspec wire a couple years ago on eBay.  It had original list price over $3000 but I paid less than 1/10th of that.  Strategically, the one speaker wire which is different (Canare 4S11) is a longer run, and the lower impedance Canare wire helps balance it out.  The Canare would have to be replaced with hand-twisted 4 quad of the milspec wire to keep things balanced.  Also Furutech locking bananas are used consistently for the Acoustat signal wiring.

7) Improved digital encoding for FM tuner.  This was a necessary step for the SAMS, and also for better time shifting of FM broadcasts.  And it sounds better too.  Previously I almost always listened to the FM Tuner (itself a classic Pioneer F-26) though Sonos (Sonos analog in and Sonos uncompressed digital out--Sonos was converting the F-26 analog to digital).  Now the FM tuner output is buffered by a Musical Fidelity X10-D, digitized by a Black Lion ADC, monitored and optimized with a Behringer DEQ 2496, and sent in AES form to my Henry Engineering AES switch (which also makes SAMS possible).  This is about as good as going through the Emotiva XSP-1 and being digitized by my Lavry, but I decided to make a separate dedicated path for convenience.  One of the big things here is that I set the volume level on the DEQ, so I don't need to make level adjustments for the FM tuner on the Tact anymore.  Having a separate level control for the tuner is very very convenient (and needed for SAMS).  For time shifting, the optical digital output from the Behringer is converted to coax with a Xantech XT-Dig-11 (which works as well as the M-Audio CO2 I used to use but are now long out of production and beginning to fail).  The coax then feeds a Marantz PMD 580 for digital recording.  I listen to the Marantz through its coax output feeding a new Kramer Tools 4x1VB coax switch, which then feeds Digital Input #3 on my Tact. 

8) AC Power Distribution was improved by getting a Furutech outlet box on the Amplifier circuit (needed for the DACs and digital splitters used on that circuit).  The two main power amplifiers themselves (Hafler and Aragon) have always plugged directly into the wall (though the Hafler now connects to AC power through an Insteon On/Off module, rated at 15A, which I believe to be lossless) and the Hafler now also has an upgraded 18 inch power cord from Cullen.  To power the miniDSPs I got a 2nd Cullen Power Box on the digital side of my system.  To power the new dedicated digital encoding path for the FM tuner I got a new metal power strip, and to power the Insteon IOLink that control the stereo for SAMS, I got a second Hammond 90 degree angled power strip.  (I love these Hammond angle strips for powering accessories and wall warts).  The thump producing Tensor Lamp is now plugged into a CJE surge suppressing power strip with 15 foot cord, which plugs into a non-audio circuit.  The frequent thumping from the hallway Bag End E-Trap has been eliminated with a Greenwave Filter.

9) The living room system was Time Aligned better than ever before.  I purchased the ARTA analysis software and figured out (and extensively documented here) what seems to be the best way to do the time alignment.

10) DVD-Audio and SACD discs are played on the Oppo UDP-205 through HDMI using my Kramer Tools De-Embedder so no analog resampling is required.  I had this de-embedder before, but had given up with it until I finally figured out how to use it correctly this year.  (And I only did that because of goading from a helpful local audio society member who insisted I could and should do this.)   When the red light on the De Embedder is switched on, it means it is converting everything to 48kHz stereo.  That's handy for DVD-Audio's like Hotel California which is encoded at 192kHz...which is above the 96kHz limit of many of my components.  Otherwise, when the red light is switched off, there is no conversion, and whatever the Oppo is putting out is obtained.  The Oppo is then set to output PCM for SACD, and it nicely outputs 88kHz for that.  Other DVD-Audios such as Fleetwood Mac are encoded at 96kHz, and I get that when I've selected the stereo tracks with the red light on.  DVD-Audio and SACD reproduction is now far more transparent than when I was resampling the analog output of the Oppo through my XSP-1 and Lavry converter, which I may still need to do in some cases.

11) HDCD Decoding.  I re-established the path to decode HDCD from titles on my server by sending the digital content through Sonos to my Denon DVD-9000, and then re-sampling the analog to digital on the Lavry.  I also started, but only started, looking deeper into this.  I obtained software that can de-compress HDCD recordings, and also determine which HDCD features particular songs use and how often.  I discovered there is (or was) a whole community of people who have been exploring HDCD.  Most now seem to believe that the HDCD digital filter selection feature is not used.  If that is true, I could just play a fairly good number of my HDCD tracks directly, without decoding and re-sampling, simply pre-uncompressing files that use the compression features.   But I have not verified it myself yet and find it hard to believe since many of the titles I think especially need HDCD decoding, such as the HDCD set from Fresh Aire, don't even use the compression features only the filter selection features.

12) Wires neatened.  After many of the changes this year, the wiring for the living room had gotten very jumbled.  I think this is especially bad when unshielded speaker wire gets twisted around digital cables and so on.  By the end of the year I had found the time to neaten up all the cabling, with help from Cable Elevators and Dark Field Mini Cable Elevators

13) Equipment failures corrected.  The living room stereo had at least 2 significant failures this year.  The 4.9 year old Emotiva XSP-1 (barely still in warranty) developed a noise in the Moving Coil section.  Emotiva repaired it for free under warranty, sending me an Audio Precision analysis of performance after the repair.  While waiting for the repaired preamp, I moved the barely used and only 2 year old XSP-1 from the bedroom to the living room where it continues to work fine.  The repaired unit went to the Bedroom Stereo.  As the display on these units tends to wear out if kept on continuously, I now turn the Emotiva XSP-1's off when not being used.  I'm now planning to automate the living room unit, automatically turning on or off as needed.  Though they don't always do this under warranty, Emotiva graciously replaced the somewhat faded display on my 4.9 year old unit while doing other repairs.  I also got to talk to an interesting Emotiva engineer.

The plate amplifier in the right SVS PB 13 ultra died and I was sent a free upgraded replacement from SVS.  The new unit is controlled through Bluetooth, which turns out to be very convenient, especially for setting the correct polarity.  At first I was shocked at how much simpler the new unit looked--no controls.  I was worried they sent me the wrong replacement.

At least 2 out of my 8 (!) Behringer DEQ 2496 units failed.  That's just a little above normal because it seems they last about 5 years on average.  (A third unit might have failed early in 2020 or late 2019, I don't recall.)  I'm working more and more on spacing these units apart for better ventilation.  The 2 failures in the bedroom system might have been pushed by a ground loop in the digital input of the top unit (which did NOT fail) which then feeds the bottom unit (two bottom units failed prematurely despite ample ventilation).  In addition to fixing the ground loop in multiple ways (belt and suspenders) by using optical connections and now-ordered unshielded ethernet jumper to the Sonos node which feeds the top Behringer, I'm thinking the miniDSP units might be more reliable, and I'm planning to migrate the bedroom system to use miniDSPs instead of Behringer DEQ's.  I don't need any of the dynamic features or displays of the DEQ's in the bedroom.  As each Behringer in the bedroom system fails (like right now) it will be replaced with a miniDSP.

As problematic as the above failures were, I had worse troubles in my video system.  The key HDBaseT digital video extender from the kitchen to the Living Room failed, and I then spent months working out a replacement.  The first 2 replacement units ordered, first from Monoprice and then Gefen, introduced serious ground loops into the Kitchen audio system.  I then decided to use the newest Gefen unit in the bedroom system and repurpose the earlier model Gefen that had been in the Bedroom for the Living Room, because the bedroom TV is only optically connected to the bedroom stereo and thereby immune to ground loops in the video system.  Then, months later, either the newest Gefen deteriorated or I just hadn't noticed it at first, the colors were constantly shifting on the bedroom TV.  I then tried a 2nd Gefen replacement model which looked very similar to my earlier Gefen model and used the same 24v power supply.  I figured because it used the 24v power supply like the earlier model, it would be immune to ground loops.  That 2nd Gefen replacement model introduced the same ground loop as the first Gefen replacement in the living room system but I was able to return it to Markertek on time to get a full refund.  Finally I obtained 2 replacement Gefen units identical to the one I bought in 2016 which work fine on all my systems and don't create ground loops--on eBay.  One of the replacement units lacked power supply, but I was also able to find a replacement 24v Gefen power supply on eBay also.

And as bad as my trouble with video extenders was, I've really been more put out by the sudden failure of my four year old HDMI 4x4 digital video matrix just a few days before Christmas switch than almost anything.  (Merry Christmas...your video system will be down until further notice.)  This ties my computer, DVR, and other video sources to all of my TV's.  Scouring the internet, I found a identical replacement to my original unit at the SolidSignal radio dealer, not wanting to repeat the endless circus I endured regarding unusable HDMI extenders.  However I neglected to pay for express shipping (I should have though of that) and so I've had to wait now 2 weeks over the holidays without my video distribution system and I still haven't heard that the replacement unit has even shipped.   I've discovered that using mere 2 way splitters can introduce endless "negotiation" issues between the sources and the monitors.  This was the second HDMI matrix switch I've owned which failed in the last 10 years.  I hate HDMI and HDCP with a purple passion and hope the people who saddled us with these endlessly problematic and failure prone "intellectual property protection" technologies will burn in hell.  Professional digital video users can use coax-based systems with solid connectors which are very reliable because they aren't endlessly trying to catch you "stealing" content.  Over the past 15 years I have spent thousands of dollars on special HDMI cables, splitters, switches, and extenders, which would have been much much cheaper (or not even necessary) except for HDMI and HDCP.  The typical HDMI switch, splitter, or extender only seems to last about 4 years...and they want you to replace them even more frequently because of endless planned obsolescence, there's a major new feature added every 2-3 years and you must upgrade everything for that.  But I don't follow the curve, I've never watched anything higher than 1080p (sometimes with 3D) and I don't have any plans to.  "Video" is just screen space to me, not magic like audio, no matter what they do.  I think you need a large screen or projector for even 4k to even mean much, and then 4k projectors and screens are way more expensive than 1080p.  Just making a 1080p image wall size makes it far more immersive than 4k in a 40 inch TV--who needs that?  And now they're talking about 8k! This makes as much sense as 192kHz sampling and above or DSD 512--also useless IMO.  I feel fairly certain, 96kHz sampling is all we need.  It hasn't been scientifically established we need anything higher than 44.1kHz.  And for what is that super fidelity for anyway?  Could something have really even been recorded that well, or require it?

The small 12V battery in my 2006 Prius died also, though it worked well enough for me to drive to the dealer and get it replaced after I used a jumper battery to boost start.  It turned out that the 12V battery was 9 years old.  I can only hope my next HDMI devices last that long.  I've got hard drives over 14 years old that are still spinning too. 

14) Listening position, relative levels, and EQ adjusted.  I am always doing this, so it's hardly worth mentioning, except that it is one of the most important things.  Recently I have decided to go for "flat as reasonable" as my target curve, instead of one rising in the bass.  This generally makes things sound more transparent, better overall, freer of bass booming, and I can play louder without irritation.  From the low end to the high end, however, there remains a very gradual downward tilt, along with slight depression around 4kHz--only the latter being deliberate but both are desirable, I believe.   A rise above 19kHz leads to a peak around 20khz where the super treble level almost exactly matches the bass again, and then quickly declines as best I can currently measure (though I should have response to 40khz at some level, perhaps 30dB down).  I suspect a rise in super sonic level to at least match the bass level, making up for a gradual treble decline, is also a good thing.  However I would prefer that bass matching peak to occur around 40kHz rather than 20kHz.  But I can't do much better with a microphone only calibrated to 23kHz and perhaps my current tweeters either.

15) Bedroom System Restoration and Upgrades.  I set up the year long disconnected Mitsubishi LT-3 (and did measurements--it had greater arm/cartridge resonances than the Ittok on my Linn).  When the repaired XSP-1 arrived, I had to reconnect the preamp and everything all over again.  Then I decided the Denon DVD-5000 "dac" in the bedroom was sounding grainy I replaced it (and the Audio GD DAC used for the TV) with Topping E30's, which still sound a tad grainy but have zero noise.   I replaced the optical connection between Behringer and E30 with a new 3 foot Lifatec, which seemed to reduce grain a bit more.  Then the Behringer DEQ 2496 used for the Revel M20 monitors died and was replaced with a new unit.  The new unit died within two weeks.  I have still not resolved that, however I determined that the Cat6a jumper from my home distribution network was wrongly a shielded STP and not the unshielded UTP cable I had intended to use.  That may have been partly responsible (along with poor quality AES implementations) for the recent bedroom Behringer and Tact failures.  AES is supposed to be resistant to ground loops not only because it is balanced but also all receivers and transmitters are supposed to be transformer coupled.  I am currently waiting on a new Cat 6a UTP jumper cable, and a second Lifatec fiber optic cable for coupling from the Sonos node to the first Behringer...another measure to break ground loops and protect the Behringers.  I am hoping that breaking the ground loops in the digital paths will reduce or eliminate the grainy sound the Bedroom Stereo has had recently too.

16) Oppo UDP 205 now used as main Streamer.  Only a few weeks before the wonderful audio party I hosted in the beginning of March 2020, I realized I could use the Oppo UDP 205 as streamer, and thereby stream high definition recordings on my server using Roon.  Previously I had done all streaming through my old Sonos nodes, which are limited to CD resolution.  The Oppo sends digital via coax to my Tact preamp through digital input #2.  The Oppo has the lowest jitter I have ever measured as well as being capable of the highest definition signals my system can handle (24/96).

17) QOBuz added.  I already had Tidal and Roon, but in 2020 I added QOBuz, which fills in some missing recordings Tidal does not have, and adds many High Definition recordings.  This didn't seem to be important until I discovered I could stream through the Oppo.

18) Tuner evaluations, tests, and repairs.  I removed the Kenwood L-1000T from the kitchen to determine how to fix the drift.  It became apparent that the power supply gets far too hot and needs vent holes in the top cover.  I tried other measures, such as loosening the side cover, which was good enough to fix the drift but not good enough to satisfy my concerns about the power supply.  I am planning to have a machine shop cut holes in the top cover.  Meanwhile I first tried the Sansui TU-D99X tuner I had been planning to give away, but was shocked at how good it was.  I kept using the Sansui for a long time, then switched to my Yamaha TX-1000, another excellent tuner, more open sounding but also more noise than the Sansui.  Finally, I finally repaired the meter lamps in the Kenwood 8300 tuner I bought a decade ago and rolled it into the kitchen.  Sadly it is higher noise and possibly even higher distortion than the other tuners, and is especially bested by the Pioneer F-26 (on a different and probably lesser antenna).  It might be better with alignment.  Having also had a few other legendary Kenwood models, the only one that has sounded good to me is an L-1000T (and I suspect the L-02T might be even better).  There were times when I thought my life had been ruined because I gave away an 8300 and kept a 7500.  Then I got a KT-917 and thought it was a joke.  Then I got a 600T and thought it was wooly sounding (but I still love the linear strength meter).  Then I said (wrongly) if only I'd kept my 8300...that must have been the best.   Present experience suggests it might be better than a 7500, but not that much.  I should have considered other brands like Pioneer more.

19) Adjusting Kitchen Surround System.  I added a Behringer DEQ to the kitchen system (the second DEQ in that system now) in order to properly adjust the levels to the two rear surround speakers, and then fine tuned both 5 and 7 channel using the AIX test disc, so surround recordings sound way better than before.  But I have no way to adjust the side surround speakers independently at this time, so a readjustment through disc menus is required to switch from 5 channel recording to 7 channel recordings with proper levels.  (With a 5 channel recording, I play both sides and rears but at a reduced level, as compared with 7 channel.)

20) Expanded Drive Space

My "music server" is my Kitchen Mac, a Late 2012 Mac Mini.  Until midyear 2020, I'd stored everything in the factory 1.1Tb Fusion drive, which was backed up with a trio of 2-4Tb backup drives.  Recently I had been constantly deleting files to keep it from maxing out, and in 2020 I created a special program to find files with identical contents and delete them.   However, this only saved about 130Gb, so I bought a 5Tb external drive, but after some thought I decided to make the 5Tb drive my first 5Tb backup drive, and repurpose one of my 2Tb drives as the "expansion" drive.  The backup drives need to be the largest drives of all, I realized.  Anyway this 2Tb drive expanded my max storage capability from 1.1 to 3.1Tb, so for the time being I have no worry about running out of space for music files.

21) New Test Equipment

I did a number of interesting technical investigations in 2020.  Some involved checking out the technical performance of equipment.  Sadly, however, I broke my ST1700A about midyear when my Tensor Lamp fell down from the "workbench" slightly above the input binding posts and knocked the "+" post off.  It would not be until the first days January 2021 that I got around to clearing the bench, examining the inside of the ST1700A, and deciding which replacement binding posts to order, and ordering them.

That possibly would not have happened had I not finally acquired a long desired piece of new test equipment, which I have not done anything with yet.  An HP 3582A.  This is HP's ultimate audio frequency spectrum analyzer.  I've seen many interesting speaker investigations done using it.  However, so far, I've only gotten about half way through the Tutorial, despite having set a goal to finish the Tutorial before buying an Earthworks M50, which I still haven't done either.

Such tests as I have done have either used ARTA, the program I bought in 2020 to do speaker time alignment and other analysis, or such primitive instruments as my long cherished Meguro MN-445B Noise Meter, which I used to exactly verify the noise fault that had arisen within my Emotiva Preamp, or one of my Fluke 8060A meters--which I use constantly, or even the program Audacity, which I used to study tonearm cartridge resonances, and Feickert Test Disc and Platter Speed app, which I used to verify my Linn has very accurate speed.

Another new, treasured, and already proven useful piece of test equipment is the Greenwave EMI Meter, which shows noise on AC lines.  This enabled me to quickly rule out the idea that failures in my bedroom system were due to AC line noise, which led me to the ultimate discovery that the Cat6a patch cable I thought was unshielded was actually shielded and introducing a ground loop into the digital input.

22) Passwords and IDs