My almost annual trip to California resulted in visiting only one currently active audiophile, the very industrious Roger who always has endless audio construction projects and modification experiments in process. Well this time I thought his sound was far better than in a long time, and possibly due to his use of actual commercial amplifiers, Manleys, which looked sufficiently muscular and I'm sure were undeniably hifi. Previously he was into SET's with a home made SET having an enormous tube. SETs can have serious rolloff, and I think his might have. However, Roger attributed the most recent improvements to damping, specifically the metallic 3M damping material he is now applying in over inch thick layers to potentiometers. (This looks like great stuff BTW and I think I will start trying it myself in applications where hockey tape wouldn't work.) He's tossed his transformer volume control (very complicated and expensive) because, in the end, he was unable to find a way to properly damp it (all those transformers!). Still present were a few of his amazing huge clamps, (everything must be clamped rigid, Roger believes) but fewer clamps than before, or so it seemed, maybe I wasn't looking hard enough.
His system IMO has generally lacked high frequency bandwidth as it's first offense. He's somewhat apologetic about that, claiming great hearing loss. However, this time it was much more extended than previously I thought, despite his still taping off the electret tweeters on his Zu speakers. It actually sounded tolerable bandwidth wise, also with new subwoofer. (Perhaps the bass even makes the highs sound better.) It even had one positive quality, solidity, which my system relatively lacks. A lot of speakers based around cone speakers in small rooms have solidity, though it's often too much in-your-face solidity, Roger's was about just right, in that one parameter.
However, come home, and the improvement otherwise in my system is staggering. I don't have a thin midrangy system like ESL-57's. With my gigantic subs, electronic EQ, and huge Acoustat 2+2's, I still rate well on solidity, though it's highly dependent on the actual crossover, EQ, delay, and other adjustments.
And then soon my system became even better. I was then so inspired to do some more oscillator sweeps, and 1/6 octave phone analyzer readings on the Stereophile Pink Noise track.
I clearly did show some loss at 100Hz in one channel. Strangely there was NO notch at 100 Hz, (though I had set a notch to 104 at one time, the size was 0.0dB) just notches at 72.6 and 130 which I changed to 72.6 and 140, which somehow made a larger difference at 100Hz than you might expect, not flat but not terribly sucked out anymore. This improved the "solidity" significantly. Note the subwoofer is crossed over at 100 Hz, but notches as high as 140 make a significant difference to the sound.
I also fine tuned the Linkwitz range notches to 2729 Hz (1/3 octave, -1.5dB) and 5200 Hz (1/2 octave, -3.5dB). These not only make for a smooth dip in the 2-3Khz range as various people have recommended, it flattens some issues with the Acoustats themselves, which actually seem to have a slight peak right where it hurts the ear the most around 6kHz and also around 2.7Khz Previously I used a single notch around 3.5kHz, but that left lumps at the new notch frequencies. I'm not sure when I zeroed out the sub 1000 Hz notches in the midrange. When I got the 2+2's at first those EQ's, which I had tuned using the 1+1's, seemed OK, but later it seemed they didn't quite fit where notches might be useful, and they weren't as much needed. I didn't photograph the midrange EQ in November when I did my first official 2+2 sweeps and adjustments. I think I might have zeroed out the sub 1000 Hz notches then, and/or added two notches above 2 khz, but they weren't exactly the same as now, or I added different sub 1000 Hz notches. Anyway, in the interests of restoring solidity, and perhaps more, I've removed all sub 1000 Hz notches for now from the midrange, and have once or twice tweaked two notches above 2kHz (there could possibly usefully be a third around 8-10 kHz, just to flatten/smooth the response, but that "artistry" will require a lot more development).
The sound even more improved, and more solid, I had accidentally moved the listening chair too far back during packing but lined up to the original tape which puts the ear about 6 inches beyond the peak of the roof, works great. I started going through my favorite "special" discs, DVD-Audios and SACD, and then just kept up playing CD's mostly, my new years resolution being to play more music, and now I'm pretty much keeping it always playing, most recently from discs since they are easy to collect from my racks (not so easy to put back). Each different method of selecting music (each different App, or physical media storage system, etc) makes you choose different music--a sadly uninvestigated phenomena.
I've also recently sweep tuned the kitchen subwoofer for greatly improved sound. It turns out the room exaggerated 41.8Hz, where I now have a -15dB notch 1/2 octave wide. With this change, FM no longer makes one sick near the sink, for example, because of throbbing bass. I may now be able to switch back from the remarkably fine Sansui TU-D99X, thin but possibly their actual finest model which introduced the Walsh-type FM decoder they patented, to my still best tuner of all time, the Kenwood L-1000T. The latter had become intolerable because of the bass exaggeration.
With these minor (though, possibly the most important) changes out of the way, I then moved on to Tweak-O-Mania!
Just before my trip I had been in crunch mode getting my house "ready" for the trip in various ways. The biggest project of the year was making the old Kimball organ redundant by sampling it, and then getting it taken by Salvation Army. But projects continued right up to the last minute, including fixing tile in the small bathroom, hoping to make my house perhaps just enough more liveable for someone to move in (which, wouldn't be expected, but there is always a remote possibility, and those possibilities are important if for nothing else than one's own self esteem--I promised to get rid of the Kimball 6 years ago for one thing, and I'd been promising to fix the tile for several years).
So anyway, I don't really mean to complain so much, but because of all the other stuff, highly visible audio project were being deliberately postponed. If I barely have enough time for all the other stuff, which indeed I barely did, just barely completing everything I'd planned to do, I wouldn't have made if I had dilly dallied with audio projects of questionable importance.
BUT NOW I COULD DO THEM!!!
So finally I had time to fix the big speaker wire messes, including the ways that both supertweeters were hooked up with big extra coils of wire and stacks of connectors that would be hard to explain to another audiophile (but could be explained, if I only had the time, and a patient enough listener).
The supertweeters are now (20 days after returning home) hooked up pretty much correctly, with the wires from the amplifier running to "connector blocks" where they are merged with the thinner gauge wire that connects to the roll-off capacitors and both supertweeters. The connector blocks are actually repurposed Furutech tightening bananas, which accept a huge gauge of input bare wire. I strip and twist a generous portion of all the wires together and shove them all into the bare wire inlet of the Furutech and then tighten the two screws as much as possible. They most connect to the two of 11 gauge wires for each polarity of the Canare 4S11 that runs up to the connector block, together with the 16 gauge wire stranded that runs to the capacitors and speaker terminals. They do this easily. This is one idea that I've sort of adopted from my friend George, who uses a special kind of copper ring for joining pairs of speaker wires by a similar method. He claims his copper ring is the best, blah, blah. But the same principle can be used with most anything that clamps onto wire, I decided, and one can hardly beat the finely gold plated copper used in the Furutech connectors.
Actually, I fear this clamping method isn't as perfect as George believes. If there is any room for oxygen, the copper will corrode, and corroded bare copper is a semiconductor.* The bare stranded wires are not being clamped tightly enough to eliminate copper corrosion. It's better to have silver plated copper in the first place (George strongly believes that silver or silver plating causes harsh sound, but that's because his reference is the softened sound he expects despite his transducers), then clamped strongly or soldered in some way that doesn't permit air oxidation. But as far as resistance, etc., the fairly large mass of wire now clamped with two screws in the Furutech connector is good enough for the supertweeters, I have decided. And it neatens up the wires, gets blocks of connectors off the floor, and it makes the wires as short as possible, with a new twist I'm also employing in the midrange. I use lower inductance and resistance wire (the Canare 4S11) for the longer runs, and the slightly higher inductance and resistance wire (my silver plated teflon coated milspec copper stranded wire) for the shorter side. It just naturally happened I had already set things up this way for the super tweeters, but I had a coil of the teflon wire on one side connected to a block of connectors because I had never had time to get around to trimming the wire connections to fit (ever since I had to move the supertweeters inboard of the Acoustats after upgrading to the Acoustat 2+2's).
(*George used to use copper stranded speaker wire that had turned sea green because of corrosion. He said it's the best just like that, determined by his listening to it. I'm not sure what kind of wire he was using when he quit playing his stereo 3 years ago, but it's certainly not silver plated. He generally likes to space wires as much as possible, which creates a huge amount of inductance. This is all NOT high fidelity to me, but it works for him. He says that what I do, and things I often say, don't make sense.)
In redoing the supertweeter speaker/amplifier wiring, I discovered that one supertweeter was formerly out of polarity, or at least so it seemed. Everything is now visibly correct from the speakers to the amplifiers.
I also had a very ugly block of connectors for the right Acoustat, where connected a short piece of 4S11 to a short piece of 16G "audiophile" wire (using polypropylene inner sleeves protecting the bare copper with the corrosive and poor dielectric contact with the vinyl covering) that actually connected to the acoustats. This ugly block of connectors sitting on the floor consisted of a pair of Furutech locking bananas, a second pair they were screwed into, and a third RadioShack Gold connector merely to keep the two pairs of pairs of Furutech connectors properly spaced.
This all became necessary when the original short piece of custom terminated 4S11 was no longer long enough, either because I have moved the 1+1's out from the wall more (which I started doing in spring of 2019) or because I switched to the 2+2's when then had to be moved as far as possible to the sides, with the supertweeters now on the inside because I can't fit them on the outside and still have a passageway through the room. So I've had this ugly block of connectors on the floor for about 6 months or more and it's bugged me every day.
My first approach, however, didn't seem fully satisfactory. I simply soldered 5 inch pieces of the teflon solid wire to the ends of the Canare 4S11. This solder joint was made in a fairly convenient but questionable way. I simply wrapped a loop of the silver coated solid wire around the stranded copper, squeezed it down as tightly as possible, and soldered with eutectic solder. After the pressure of the iron was removed, the wire always slinked a bit, making me worry about cold solder. I worked on this through numerous attempts for two hours, and finally decided it was good enough, the joint looked smooth all around, just not quite as shiny as I would have liked. I then was unable to find my "rescue tape" and all my shrink wrap was too small, so I had to cover up the joints with vinyl electrical tape.
That got rid of the connector blocks, but it looked ugly to audiophile eyes and thinking. It would be much better to use a single piece of wire, preferably the 10G solid core silver plated teflon coated hand twisted wire I use for most everything else now. But I would only want to do this if I had a locking banana of the "straight" kind, and not the "bent" kind like all of my Furutechs (which I just seem to have run out of again, I buy them in bunches now).
Well, it turned out that in fixing one side of the supertweeter wiring, I freed up a short piece of wire that had exactly the right kind of "straight" locking banana I needed, AND it had locking screws. (I have some other pairs, of terminated 4S11 with straight locking bananas, but the 4S11 wires are crimped into the bananas, not screwed.)
These straight locking bananas were just what I needed to take one existing short piece of teflon twisted pair wiring and put it to use for the right Acoustat. Crawling around the floor and especially making the connections behind the highly modified QSC ABX box I use for amplifier switching still took almost two hours of work, but finally the right Acoustat was wired nicely by audiophile standards, with no electrical tape or ugly solder joints.
At first, however, it sounded harsh. I had the wire almost 18 inches off the ground, going up and over the Acoustat interfaces and the stack of digital equipment down to the ABX box connectors. It occurred to me this "high" run could be picking up distant interference, or perhaps vibration.
I lowered the wire by bending it (solid core wire must be bent to each new shape) down closer but still about 7 inches above the floor mostly. I also "damped" the piece of wire by hanging a Velco strap tied to a loop of phone wire serving as a dumb weight, in the middle of the wire run.
At this point it sounded great, and the soundfield seemed more unified than ever before, or at least a long time.
I then remembered that by switching from 4S11 to 10G twisted pair I was approximately doubling the inductance and 50% increasing the resistance. This would make this shorter run of wire from the ABX box more similar to the twice-as-long wire (now 4S11) running to the other speaker. So, for the first time in a long time, perhaps, I have basically equal speaker wire inductance on both sides, and the resistance is fairly close also.
I've never been one of those people to axiomatically cut all speaker wires for stereo channels to the same length. I know this has virtues, but it then leaves you with useless coils of wire, which may better pick up noise and have leakage characteristics. And with all the wires I have, it gets maddening very quickly. So instead I terminate each wire to the more-or-less exact length needed (usually with some extra margin, but over time, I've been finding margins not useful anyway, and I just cut things pretty close to the lengths needed).
So just 20 days back home, I've made major improvements some delayed perhaps by years, and I'm enjoying music more than ever.
The rattle in the right Acoustat has not been noticeable, even though I'm consistently playing at the "realistic" level (1.0V input max to the Hafler which is just below it's rated sensitivity for full power).
His system IMO has generally lacked high frequency bandwidth as it's first offense. He's somewhat apologetic about that, claiming great hearing loss. However, this time it was much more extended than previously I thought, despite his still taping off the electret tweeters on his Zu speakers. It actually sounded tolerable bandwidth wise, also with new subwoofer. (Perhaps the bass even makes the highs sound better.) It even had one positive quality, solidity, which my system relatively lacks. A lot of speakers based around cone speakers in small rooms have solidity, though it's often too much in-your-face solidity, Roger's was about just right, in that one parameter.
However, come home, and the improvement otherwise in my system is staggering. I don't have a thin midrangy system like ESL-57's. With my gigantic subs, electronic EQ, and huge Acoustat 2+2's, I still rate well on solidity, though it's highly dependent on the actual crossover, EQ, delay, and other adjustments.
And then soon my system became even better. I was then so inspired to do some more oscillator sweeps, and 1/6 octave phone analyzer readings on the Stereophile Pink Noise track.
I clearly did show some loss at 100Hz in one channel. Strangely there was NO notch at 100 Hz, (though I had set a notch to 104 at one time, the size was 0.0dB) just notches at 72.6 and 130 which I changed to 72.6 and 140, which somehow made a larger difference at 100Hz than you might expect, not flat but not terribly sucked out anymore. This improved the "solidity" significantly. Note the subwoofer is crossed over at 100 Hz, but notches as high as 140 make a significant difference to the sound.
I also fine tuned the Linkwitz range notches to 2729 Hz (1/3 octave, -1.5dB) and 5200 Hz (1/2 octave, -3.5dB). These not only make for a smooth dip in the 2-3Khz range as various people have recommended, it flattens some issues with the Acoustats themselves, which actually seem to have a slight peak right where it hurts the ear the most around 6kHz and also around 2.7Khz Previously I used a single notch around 3.5kHz, but that left lumps at the new notch frequencies. I'm not sure when I zeroed out the sub 1000 Hz notches in the midrange. When I got the 2+2's at first those EQ's, which I had tuned using the 1+1's, seemed OK, but later it seemed they didn't quite fit where notches might be useful, and they weren't as much needed. I didn't photograph the midrange EQ in November when I did my first official 2+2 sweeps and adjustments. I think I might have zeroed out the sub 1000 Hz notches then, and/or added two notches above 2 khz, but they weren't exactly the same as now, or I added different sub 1000 Hz notches. Anyway, in the interests of restoring solidity, and perhaps more, I've removed all sub 1000 Hz notches for now from the midrange, and have once or twice tweaked two notches above 2kHz (there could possibly usefully be a third around 8-10 kHz, just to flatten/smooth the response, but that "artistry" will require a lot more development).
The sound even more improved, and more solid, I had accidentally moved the listening chair too far back during packing but lined up to the original tape which puts the ear about 6 inches beyond the peak of the roof, works great. I started going through my favorite "special" discs, DVD-Audios and SACD, and then just kept up playing CD's mostly, my new years resolution being to play more music, and now I'm pretty much keeping it always playing, most recently from discs since they are easy to collect from my racks (not so easy to put back). Each different method of selecting music (each different App, or physical media storage system, etc) makes you choose different music--a sadly uninvestigated phenomena.
I've also recently sweep tuned the kitchen subwoofer for greatly improved sound. It turns out the room exaggerated 41.8Hz, where I now have a -15dB notch 1/2 octave wide. With this change, FM no longer makes one sick near the sink, for example, because of throbbing bass. I may now be able to switch back from the remarkably fine Sansui TU-D99X, thin but possibly their actual finest model which introduced the Walsh-type FM decoder they patented, to my still best tuner of all time, the Kenwood L-1000T. The latter had become intolerable because of the bass exaggeration.
With these minor (though, possibly the most important) changes out of the way, I then moved on to Tweak-O-Mania!
Just before my trip I had been in crunch mode getting my house "ready" for the trip in various ways. The biggest project of the year was making the old Kimball organ redundant by sampling it, and then getting it taken by Salvation Army. But projects continued right up to the last minute, including fixing tile in the small bathroom, hoping to make my house perhaps just enough more liveable for someone to move in (which, wouldn't be expected, but there is always a remote possibility, and those possibilities are important if for nothing else than one's own self esteem--I promised to get rid of the Kimball 6 years ago for one thing, and I'd been promising to fix the tile for several years).
So anyway, I don't really mean to complain so much, but because of all the other stuff, highly visible audio project were being deliberately postponed. If I barely have enough time for all the other stuff, which indeed I barely did, just barely completing everything I'd planned to do, I wouldn't have made if I had dilly dallied with audio projects of questionable importance.
BUT NOW I COULD DO THEM!!!
So finally I had time to fix the big speaker wire messes, including the ways that both supertweeters were hooked up with big extra coils of wire and stacks of connectors that would be hard to explain to another audiophile (but could be explained, if I only had the time, and a patient enough listener).
The supertweeters are now (20 days after returning home) hooked up pretty much correctly, with the wires from the amplifier running to "connector blocks" where they are merged with the thinner gauge wire that connects to the roll-off capacitors and both supertweeters. The connector blocks are actually repurposed Furutech tightening bananas, which accept a huge gauge of input bare wire. I strip and twist a generous portion of all the wires together and shove them all into the bare wire inlet of the Furutech and then tighten the two screws as much as possible. They most connect to the two of 11 gauge wires for each polarity of the Canare 4S11 that runs up to the connector block, together with the 16 gauge wire stranded that runs to the capacitors and speaker terminals. They do this easily. This is one idea that I've sort of adopted from my friend George, who uses a special kind of copper ring for joining pairs of speaker wires by a similar method. He claims his copper ring is the best, blah, blah. But the same principle can be used with most anything that clamps onto wire, I decided, and one can hardly beat the finely gold plated copper used in the Furutech connectors.
Actually, I fear this clamping method isn't as perfect as George believes. If there is any room for oxygen, the copper will corrode, and corroded bare copper is a semiconductor.* The bare stranded wires are not being clamped tightly enough to eliminate copper corrosion. It's better to have silver plated copper in the first place (George strongly believes that silver or silver plating causes harsh sound, but that's because his reference is the softened sound he expects despite his transducers), then clamped strongly or soldered in some way that doesn't permit air oxidation. But as far as resistance, etc., the fairly large mass of wire now clamped with two screws in the Furutech connector is good enough for the supertweeters, I have decided. And it neatens up the wires, gets blocks of connectors off the floor, and it makes the wires as short as possible, with a new twist I'm also employing in the midrange. I use lower inductance and resistance wire (the Canare 4S11) for the longer runs, and the slightly higher inductance and resistance wire (my silver plated teflon coated milspec copper stranded wire) for the shorter side. It just naturally happened I had already set things up this way for the super tweeters, but I had a coil of the teflon wire on one side connected to a block of connectors because I had never had time to get around to trimming the wire connections to fit (ever since I had to move the supertweeters inboard of the Acoustats after upgrading to the Acoustat 2+2's).
(*George used to use copper stranded speaker wire that had turned sea green because of corrosion. He said it's the best just like that, determined by his listening to it. I'm not sure what kind of wire he was using when he quit playing his stereo 3 years ago, but it's certainly not silver plated. He generally likes to space wires as much as possible, which creates a huge amount of inductance. This is all NOT high fidelity to me, but it works for him. He says that what I do, and things I often say, don't make sense.)
In redoing the supertweeter speaker/amplifier wiring, I discovered that one supertweeter was formerly out of polarity, or at least so it seemed. Everything is now visibly correct from the speakers to the amplifiers.
I also had a very ugly block of connectors for the right Acoustat, where connected a short piece of 4S11 to a short piece of 16G "audiophile" wire (using polypropylene inner sleeves protecting the bare copper with the corrosive and poor dielectric contact with the vinyl covering) that actually connected to the acoustats. This ugly block of connectors sitting on the floor consisted of a pair of Furutech locking bananas, a second pair they were screwed into, and a third RadioShack Gold connector merely to keep the two pairs of pairs of Furutech connectors properly spaced.
This all became necessary when the original short piece of custom terminated 4S11 was no longer long enough, either because I have moved the 1+1's out from the wall more (which I started doing in spring of 2019) or because I switched to the 2+2's when then had to be moved as far as possible to the sides, with the supertweeters now on the inside because I can't fit them on the outside and still have a passageway through the room. So I've had this ugly block of connectors on the floor for about 6 months or more and it's bugged me every day.
My first approach, however, didn't seem fully satisfactory. I simply soldered 5 inch pieces of the teflon solid wire to the ends of the Canare 4S11. This solder joint was made in a fairly convenient but questionable way. I simply wrapped a loop of the silver coated solid wire around the stranded copper, squeezed it down as tightly as possible, and soldered with eutectic solder. After the pressure of the iron was removed, the wire always slinked a bit, making me worry about cold solder. I worked on this through numerous attempts for two hours, and finally decided it was good enough, the joint looked smooth all around, just not quite as shiny as I would have liked. I then was unable to find my "rescue tape" and all my shrink wrap was too small, so I had to cover up the joints with vinyl electrical tape.
That got rid of the connector blocks, but it looked ugly to audiophile eyes and thinking. It would be much better to use a single piece of wire, preferably the 10G solid core silver plated teflon coated hand twisted wire I use for most everything else now. But I would only want to do this if I had a locking banana of the "straight" kind, and not the "bent" kind like all of my Furutechs (which I just seem to have run out of again, I buy them in bunches now).
Well, it turned out that in fixing one side of the supertweeter wiring, I freed up a short piece of wire that had exactly the right kind of "straight" locking banana I needed, AND it had locking screws. (I have some other pairs, of terminated 4S11 with straight locking bananas, but the 4S11 wires are crimped into the bananas, not screwed.)
These straight locking bananas were just what I needed to take one existing short piece of teflon twisted pair wiring and put it to use for the right Acoustat. Crawling around the floor and especially making the connections behind the highly modified QSC ABX box I use for amplifier switching still took almost two hours of work, but finally the right Acoustat was wired nicely by audiophile standards, with no electrical tape or ugly solder joints.
At first, however, it sounded harsh. I had the wire almost 18 inches off the ground, going up and over the Acoustat interfaces and the stack of digital equipment down to the ABX box connectors. It occurred to me this "high" run could be picking up distant interference, or perhaps vibration.
I lowered the wire by bending it (solid core wire must be bent to each new shape) down closer but still about 7 inches above the floor mostly. I also "damped" the piece of wire by hanging a Velco strap tied to a loop of phone wire serving as a dumb weight, in the middle of the wire run.
At this point it sounded great, and the soundfield seemed more unified than ever before, or at least a long time.
I then remembered that by switching from 4S11 to 10G twisted pair I was approximately doubling the inductance and 50% increasing the resistance. This would make this shorter run of wire from the ABX box more similar to the twice-as-long wire (now 4S11) running to the other speaker. So, for the first time in a long time, perhaps, I have basically equal speaker wire inductance on both sides, and the resistance is fairly close also.
I've never been one of those people to axiomatically cut all speaker wires for stereo channels to the same length. I know this has virtues, but it then leaves you with useless coils of wire, which may better pick up noise and have leakage characteristics. And with all the wires I have, it gets maddening very quickly. So instead I terminate each wire to the more-or-less exact length needed (usually with some extra margin, but over time, I've been finding margins not useful anyway, and I just cut things pretty close to the lengths needed).
So just 20 days back home, I've made major improvements some delayed perhaps by years, and I'm enjoying music more than ever.
The rattle in the right Acoustat has not been noticeable, even though I'm consistently playing at the "realistic" level (1.0V input max to the Hafler which is just below it's rated sensitivity for full power).
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