It was a rainy day, so contemplating things.
Like most, I have had a long history in audio from high school days with a Knight mono tube hand-me-down to now. Spent time building my own tube, bi-polar and MOSFET amps. Learned a lot on which defects in amps played better with which defects in speakers.
I wound up with my own 60W MOSFET for many years. Used an early "Muse" DAC that had an audible improvement over even my old Rotel CD player that was very good. Sounded quite good IMHO. Better than the Rotel, Hafler, B&K, Parasound amps it followed. None of them bad, I just liked mine better. Musical and relaxed. Measured pretty well too. I have my own speakers, but they still hold up well or better than any I can afford. Seas based.
Anyway, I decided to "upgrade" one last time. I figured, next time will be a table radio in a nursing home, so have fun now.
Started with an SMSL then Topping DAC as they were so highly rated. Unstable, distortion spikes, issues. Anyway, got a Schiit Asgard pre/DAC/head amp box. Very clean. Very. Then I got a Parasound 2125 amp as my old one needed re-capping, never put in any output mute or safety features. Very disappointed overall. Put them in removing my old Nalamichi ps-5 preamp. Clean, but harsh to my ears. Measures .00-something insane low distortion, gobs of power, plenty of power supply for dynamics, just not as friendly. I know, "Friendly" is not an easy to measure parameter.
Where this is going.
The new electronics are at least an order magnitude lower distortion. As time has passed, they seem better. Not sure as nice as I remember, my old stuff, but looking back through rose colored glasses et al. So the point of this thread, can we re-train our expectations for a lower distortion, or do we just naturally prefer the low order even harmonics? Have I lived with a "cleaner" system long enough it is what sounds correct now?
Or is something else at play? I remember fondly amps like the Aragon, Nak Stasis, Levinson 20 something, Roland, an early Krell, Linn, Quad, and a few others.
In my thinking about replacing the Parasound, I have listened to several higher end amps recently. One might expect as the price goes up, the differences would be smaller. Not what I am hearing.
Moon, Atoll, and Hegel sound very nice. Or I would say I don't find them to sound. Krell, Rotel, Marantz, Halo, Arcam all sounded decidedly different. On paper all are superb units. Why in the $2000 to $5000 and up range such a difference?
In conclusion, I am going to rebuild my old amp and see which I prefer. Sorry local stores, not going to plunk down the bucks for a new amp just yet. And if I do another pair of speakers, they would be my own again as I have not heard any under about 4 grand I would want to live with. 5K for speakers would not pass the WAF. She wants the master bath done first.
Like most, I have had a long history in audio from high school days with a Knight mono tube hand-me-down to now. Spent time building my own tube, bi-polar and MOSFET amps. Learned a lot on which defects in amps played better with which defects in speakers.
I wound up with my own 60W MOSFET for many years. Used an early "Muse" DAC that had an audible improvement over even my old Rotel CD player that was very good. Sounded quite good IMHO. Better than the Rotel, Hafler, B&K, Parasound amps it followed. None of them bad, I just liked mine better. Musical and relaxed. Measured pretty well too. I have my own speakers, but they still hold up well or better than any I can afford. Seas based.
Anyway, I decided to "upgrade" one last time. I figured, next time will be a table radio in a nursing home, so have fun now.
Started with an SMSL then Topping DAC as they were so highly rated. Unstable, distortion spikes, issues. Anyway, got a Schiit Asgard pre/DAC/head amp box. Very clean. Very. Then I got a Parasound 2125 amp as my old one needed re-capping, never put in any output mute or safety features. Very disappointed overall. Put them in removing my old Nalamichi ps-5 preamp. Clean, but harsh to my ears. Measures .00-something insane low distortion, gobs of power, plenty of power supply for dynamics, just not as friendly. I know, "Friendly" is not an easy to measure parameter.
Where this is going.
The new electronics are at least an order magnitude lower distortion. As time has passed, they seem better. Not sure as nice as I remember, my old stuff, but looking back through rose colored glasses et al. So the point of this thread, can we re-train our expectations for a lower distortion, or do we just naturally prefer the low order even harmonics? Have I lived with a "cleaner" system long enough it is what sounds correct now?
Or is something else at play? I remember fondly amps like the Aragon, Nak Stasis, Levinson 20 something, Roland, an early Krell, Linn, Quad, and a few others.
In my thinking about replacing the Parasound, I have listened to several higher end amps recently. One might expect as the price goes up, the differences would be smaller. Not what I am hearing.
Moon, Atoll, and Hegel sound very nice. Or I would say I don't find them to sound. Krell, Rotel, Marantz, Halo, Arcam all sounded decidedly different. On paper all are superb units. Why in the $2000 to $5000 and up range such a difference?
In conclusion, I am going to rebuild my old amp and see which I prefer. Sorry local stores, not going to plunk down the bucks for a new amp just yet. And if I do another pair of speakers, they would be my own again as I have not heard any under about 4 grand I would want to live with. 5K for speakers would not pass the WAF. She wants the master bath done first.
I totally disagree. I, and more so my wife, are very sensitive to simple harmonic distortion and it is well documented by blind A/B testing the natural human preference for low order even harmonics and the irritating and harshness of higher order odd harmonics. Now what level is relevant? I would agree the difference between .00001 and .01 is irreverent and open to "Madison Ave" engineering. We seem to be far more insensitive to distortion below 500 Hz than above, which is a good thing as building subs that can play 98 dB, 80 Hz, @ 1M below 1% is more than a challenge. Been there, done that. I know for a fact how sensitive my wife is.
I would suggest, and we may agree or not, that there are many other parameters, some easily measurable such as linear distortion or compression. I can also tell you we can hear the differences between two otherwise identical amplifiers, one using dominant pole compensation and the other transient miller. The measurable differences are below .01% HD, but the difference is about the same level of distortion at all frequencies for Miller and the higher at low/mid but decreasing with dominant pole. I did the builds and did the tests.
I also suggest, it could be a threshold of the total pipe, from creation to your ears. Is that last .1% enough to bother you considering the hundreds of stages of processing from mic to ears? Where we may hear such a large difference between two amps with excellent measurement, is one just that little bit over our threshold? I can't answer, I just know I can hear the difference clearly and my wife can with the advantage of not caring how much effort I put into a build or what I paid for it, I get simple yes/no feedback from her. Consistently. I went as far as trying to trick her to no avail.
I find linear equalization to be not as critical as long as it is not severe and within what your brain expects for the ambient parameters of the room. Your brain does a lot of eq for you. However, I can clearly hear .5dB differences in eq through the midrange. Maybe you are fortunate enough, at least for your wallet, not to be so sensitive. Maybe it is the music you listen to. A good Julian Bream recording will clearly identify amplifier differences as it will make the base strings sound metallic. Joni Mitchel can shred many tweeters as can Harry James. Tracy Chapman can sound just plain not quite right.
I would suggest, and we may agree or not, that there are many other parameters, some easily measurable such as linear distortion or compression. I can also tell you we can hear the differences between two otherwise identical amplifiers, one using dominant pole compensation and the other transient miller. The measurable differences are below .01% HD, but the difference is about the same level of distortion at all frequencies for Miller and the higher at low/mid but decreasing with dominant pole. I did the builds and did the tests.
I also suggest, it could be a threshold of the total pipe, from creation to your ears. Is that last .1% enough to bother you considering the hundreds of stages of processing from mic to ears? Where we may hear such a large difference between two amps with excellent measurement, is one just that little bit over our threshold? I can't answer, I just know I can hear the difference clearly and my wife can with the advantage of not caring how much effort I put into a build or what I paid for it, I get simple yes/no feedback from her. Consistently. I went as far as trying to trick her to no avail.
I find linear equalization to be not as critical as long as it is not severe and within what your brain expects for the ambient parameters of the room. Your brain does a lot of eq for you. However, I can clearly hear .5dB differences in eq through the midrange. Maybe you are fortunate enough, at least for your wallet, not to be so sensitive. Maybe it is the music you listen to. A good Julian Bream recording will clearly identify amplifier differences as it will make the base strings sound metallic. Joni Mitchel can shred many tweeters as can Harry James. Tracy Chapman can sound just plain not quite right.
So, what if your end of the pipe adds something that isnt there upstream, yet makes the listening experience more pleasant - for you?
Thinking 12AX7 triodes strapped at an amplifier's input, as deliberate 2nd generator. Its been done; I saw it in a commercial amp design here.
Another would be dynamic range expansion, which, some are fond of.
Speakers, of course, OB in particular cast an illusion which may not "be there" in the pipe coming in, yet provides to the listener a fascinating soundscape. I'm sure there are listeners so pure that they consider this effect a form of distortion. Pleasant as it may be.
I feel fortunate for the hearing I've got at my age. When out on the street, i can hear the car coming up behind me, coming at me from in front; I can cross at a steep angle without looking with 100% assurance there's nothing that's going to intercept. I can hear the airplane, the geese above, my feet hitting the ground. The kid practicing his drum set in that house's garage - which I can immediately tell is no ones stereo, BTW. The marching band at the highschool a mile away.
I too realize it's only a matter of time before I'm in a bed, with an alexa type device on a nightstand, with a hearing aid in my one good ear. So I applaud your "last" effort to get a better game on. Me? I've got a lot of music to listen to; maybe more than I can even get to before it all turns bad. I'll fiddle-f with small things like USB to I2Cs, reverse matching transformers, maybe even some 96k source which I'm finding sounds better. Too bad I dont have any, relative to the more than enough 44.1 stuff.
Looking at this post initially, I thought I'd have nothing to say.
Thinking 12AX7 triodes strapped at an amplifier's input, as deliberate 2nd generator. Its been done; I saw it in a commercial amp design here.
Another would be dynamic range expansion, which, some are fond of.
Speakers, of course, OB in particular cast an illusion which may not "be there" in the pipe coming in, yet provides to the listener a fascinating soundscape. I'm sure there are listeners so pure that they consider this effect a form of distortion. Pleasant as it may be.
I feel fortunate for the hearing I've got at my age. When out on the street, i can hear the car coming up behind me, coming at me from in front; I can cross at a steep angle without looking with 100% assurance there's nothing that's going to intercept. I can hear the airplane, the geese above, my feet hitting the ground. The kid practicing his drum set in that house's garage - which I can immediately tell is no ones stereo, BTW. The marching band at the highschool a mile away.
I too realize it's only a matter of time before I'm in a bed, with an alexa type device on a nightstand, with a hearing aid in my one good ear. So I applaud your "last" effort to get a better game on. Me? I've got a lot of music to listen to; maybe more than I can even get to before it all turns bad. I'll fiddle-f with small things like USB to I2Cs, reverse matching transformers, maybe even some 96k source which I'm finding sounds better. Too bad I dont have any, relative to the more than enough 44.1 stuff.
Looking at this post initially, I thought I'd have nothing to say.
When you're young, everything is better, you're discovering new stuff all of the time. You pick up a book, and read it cover to cover, you listen to music and you just want to listen to it again and again, you watch a film and you're obsessed with it for months. When you're old, you pick up a book, read a few pages and realize you've read similar stories before ( if you don't doze off before that stage), you listen to music, but it doesn't have the magic it once had. What you need ( as Mr Burns found out ) is the blood of a young boy to feel what it's like to be young again, no upgrades will ever bring your youth back, sorry.
I think some people can learn to hear a lot of things that most people's brains don't react to as something significant. People can learn to hear relative pitch, transcribe a symphony, hear low level distortion, hear soundstage 'depth,' and hear various other things. Some people do learn those things while other people don't share the same interest. Also, some people are born with different innate mental organization, and or with somewhat different body physiology. Maybe not everyone is cutout to a good listener, don't know.
The cost of high end audio gear is dominated by two factors: (1) the cost of the case, which has some kind of jewelry appeal. Boxes that don't look good don't sell very well in that market segment; and (2) sales volumes of high end audio gear tend be in the very low numbers. If a piece sells a few hundred units in the product's lifetime, that's good. The most expensive pieces might sell one or two per year. As a result the markup on high end audio gear has to be about six times the incremental cost of producing one unit. The markup on some items may be even higher, such as is sometimes seen for cables.
It means that in the $2000 to $5000 range, the cost of making one unit has to be only a few hundred dollars at most, and most of that expense will be for the case. Maybe a fair amount for a fancy looking shipping box too.
The above being the case in that market segment, the really good stuff is probably going to retail for $6000 and above. That's just the economics of it.
Another factor is that every high end audio designer has different ideas about what makes for a good amplifier. Not of them are equally correct. What makes for good sound is not entirely predicted by AP measurements, so it means some subjective decision making is likely involved.
Gad, how depressing. Glad to say I am not there yet. Granted I don't read as much as I did because I can't seem to get glasses that don't cause me too much eye strain, but a day without learning is a wasted day, and I have never felt like I have any to waste. Maybe it was the time I almost popped off the side of a mountain, I realized one must not ever waste a day.
I never obsessed with a movie or record. There was always, and still is, something new to see or watch. The best part of listening to several amps and speakers ( which I decided not to buy) was finding more music!
When I get to the stage you describe, then my final music system will be a table radio in the nursing home. I would like to say kicking and screaming, but I guess by then, it too will be gone. Not looking to regain my youth, but in a position I can at least pay for a little better than I could when younger.
Yes, adding even order distortion is sometimes done. One does not need tubes, but a slight imbalance if the input LTP will do the trick. ( I have to remember exactly, it has been a while) I believe the current craze for tubes is mostly mythology. I looked into tubes a while back and built a couple amps. The best of them were like pouring warm butter over your music. Maybe fine for Cello solo, but not for a Swing band or Led Zeppelin.
I can agree with cracked case.
Not depressing. I wouldn’t wish to be forever “young”.
Realistic yes. Focal point and angle of approach change with age and I am glad I experience that change .
The process of de-mything in audio is interesting (measure, listen, evaluate).
Getting deeper into music is rewarding.
And yes, a table top radio (or a portable one) can be enough for me.
If you are looking for an affordable way to experiment with shaping the distortion profile, check this. https://www.firstwatt.com/pdf/art_h2_v1.pdf
George
Not depressing. I wouldn’t wish to be forever “young”.
Realistic yes. Focal point and angle of approach change with age and I am glad I experience that change .
The process of de-mything in audio is interesting (measure, listen, evaluate).
Getting deeper into music is rewarding.
And yes, a table top radio (or a portable one) can be enough for me.
If you are looking for an affordable way to experiment with shaping the distortion profile, check this. https://www.firstwatt.com/pdf/art_h2_v1.pdf
George
I have a Benchmark AHB2 power amp, one of the lowest distortion amps in the world. The main speakers here are Sound Lab electrostatic panels, some very accurate and low distortion speakers. The lowest octave from 14Hz to 28Hz is reproduced by Rel subwoofers.
Benchmark AHB2 Power Amplifier - Benchmark Media Systems
https://www.soundlabspeakers.com/majestic/
Also have a modified Aragon 8008 Mk II power amp.
Aragon - 8008 mkII (Klipsch)
The Benchmark amp has audibly lower distortion than the Aragon. However, in a direct A/B comparison between the two power amps, the Aragon won the listening tests. It wasn't because of anything to do with distortion. It had to do with audible accuracy of reproduction. In other words, there is more to good, accurate, credible SQ than AP figure of merit tests necessarily predict. One particular shortcoming of the Benchmark AHB2 was that a few small details of sound seemed to be overly attenuated or else missing. It was something new to me, but I later heard claims that about amplifiers using too much global feedback doing that. What it actually sounded like to my ears was like AHB2 might have a little noise floor modulation going on with the audio signal. Perhaps that is something that can sometimes be an inadvertent side effect of too much global feedback, don't know. Bottom line is the Aragon is the power amp that gets used, and the Benchmark sits unused. Anyone who values low distortion over anything and everything else is welcome to make me an offer for AHB2 by PM.
Benchmark AHB2 Power Amplifier - Benchmark Media Systems
https://www.soundlabspeakers.com/majestic/
Also have a modified Aragon 8008 Mk II power amp.
Aragon - 8008 mkII (Klipsch)
The Benchmark amp has audibly lower distortion than the Aragon. However, in a direct A/B comparison between the two power amps, the Aragon won the listening tests. It wasn't because of anything to do with distortion. It had to do with audible accuracy of reproduction. In other words, there is more to good, accurate, credible SQ than AP figure of merit tests necessarily predict. One particular shortcoming of the Benchmark AHB2 was that a few small details of sound seemed to be overly attenuated or else missing. It was something new to me, but I later heard claims that about amplifiers using too much global feedback doing that. What it actually sounded like to my ears was like AHB2 might have a little noise floor modulation going on with the audio signal. Perhaps that is something that can sometimes be an inadvertent side effect of too much global feedback, don't know. Bottom line is the Aragon is the power amp that gets used, and the Benchmark sits unused. Anyone who values low distortion over anything and everything else is welcome to make me an offer for AHB2 by PM.
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This might be checked when observing the THD+N profile rather than the THD only.
George
May not want to give up on that Parasound just yet, can be pretty neutral, imo. The original smaller bypass caps are pretty “sizzly” sounding for starters. Excellent design, just not the very best execution but easily fixed. John may not agree, and I fully understand that the production was out of his control also, but he doesn’t have to listen to the one in my house either, so…
Now if they’d used parts from Reliable Capacitor, I wouldn’t be mentioning that.
As far as the difference between the tube amps we were weaned from to the crystal clear solid state amps, I believe it is a compromise, currently anyways. I have preferred to use SS amps, but with a bit of bias, line conditioning, other power supply help in order to help prevent the amplification of noise that would be otherwise be filtered via a highly rolled off treble as found in most tube amps. I donated all my tube amps in 1995 or so.
Now if they’d used parts from Reliable Capacitor, I wouldn’t be mentioning that.
As far as the difference between the tube amps we were weaned from to the crystal clear solid state amps, I believe it is a compromise, currently anyways. I have preferred to use SS amps, but with a bit of bias, line conditioning, other power supply help in order to help prevent the amplification of noise that would be otherwise be filtered via a highly rolled off treble as found in most tube amps. I donated all my tube amps in 1995 or so.
You mean people perceiving things. Whether they actually heard it or not would be confirmed after evaluation.
I'm not sure what kind of amps you are talking about but in sound reproduction world, the quality of equipment is judged on its level of fidelity.
Wow, Aragon must be real bad amplifier, despite the high price. Either that or Benchmark amp veers off the industry standard so far away that it becomes audibly different. The third possibility is that so called "direct A/B comparison" (quoted below) wasn't objectively done with level matching, double blind and quick switching.
There are some people, including a large percentage of another very popular audio forum that involves panthers, that seems to think that power amps are easier to evaluate than they are.
Traditional AP testing should tell us everything, but it doesn't really. DACs and a lot of headphone amps and preamps behave enough like a monolithic device during normal usage that the testing can be pretty simple. A lot of power amps really don't behave this way. They handle big currents, and parts get hot... and drift. Long-term drift (over the course of several minutes) is easy to observe, drift due to quick changes in die temperature are a moderate pain in the butt to see.
Power amps also have to drive a huge, horrifying array of loads, some of which are quite cruel (2 ohm reactive loads, anyone?).
I don't trust myself to assess an amp by ear. Some people may very well be able to, but I'm not one of them. I have the attention span of a squirrel, and I can rarely quantify exactly what I hear.
I also take a single distortion sweep into a 4 ohm or 8 ohm resistive load with a (very large) grain of salt, since there are certainly bad behaviors that aren't obvious in this kind of test.
AHB2s pretty much never come up at surplus, and I'm not made of money. As such, I haven't gotten my hands on one and I don't have any solid opinions on them. I suspect that they are an excellent and well-designed amplifier, but I have yet to confirm that they don't have any bad behaviors.
Traditional AP testing should tell us everything, but it doesn't really. DACs and a lot of headphone amps and preamps behave enough like a monolithic device during normal usage that the testing can be pretty simple. A lot of power amps really don't behave this way. They handle big currents, and parts get hot... and drift. Long-term drift (over the course of several minutes) is easy to observe, drift due to quick changes in die temperature are a moderate pain in the butt to see.
Power amps also have to drive a huge, horrifying array of loads, some of which are quite cruel (2 ohm reactive loads, anyone?).
I don't trust myself to assess an amp by ear. Some people may very well be able to, but I'm not one of them. I have the attention span of a squirrel, and I can rarely quantify exactly what I hear.
I also take a single distortion sweep into a 4 ohm or 8 ohm resistive load with a (very large) grain of salt, since there are certainly bad behaviors that aren't obvious in this kind of test.
AHB2s pretty much never come up at surplus, and I'm not made of money. As such, I haven't gotten my hands on one and I don't have any solid opinions on them. I suspect that they are an excellent and well-designed amplifier, but I have yet to confirm that they don't have any bad behaviors.
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My friends who design such products agree that poor measurements are bad. However, neither of them is interested in the competition for best looking AP numbers. They value subjective SQ too. No excuse for a 'thin' midrange nor for 'sterile' sound, no matter how well an amp measures. For one of the guys, the quality of the stereo illusion of there being a soundstage with expansive, credible width and depth is more important than a little bit of very low order harmonic distortion. If there has to be an engineering trade off, I don't think he is wrong.
Regarding AHB2, aside from the issue I already mentioned it is only specified down to 3-ohms. In many ways it is a very fine amplifier. It just isn't quite perfect, at least not in my eyes.
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