I'd rather accept it , look into it for evidence and go from there .I'm not sure we should believe what vendor is saying about amps..
That's my feeling but it's enough to peak interest , for me at least .
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Amplifiers can you hear a diffrence?
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I say that, unless he can fortify his claim that his wife/GF heard the difference from the kitchen, we ignore it on the account he had one too many when writing that.
Blumlein 88
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If he had wife and girlfriend in the kitchen at the same time, I'm not surprised they didn't hear it.I say that, unless he can fortify his claim that his wife/GF heard the difference from the kitchen, we ignore it on the account he had one too many when writing that.
Blumlein 88
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I don't know what to think either. I would remind that usually measurements of amps are with resistive loads and not with real speakers.
I know I've mentioned it before, but the Swedish AES results of series amp testing are interesting. They did that blind and only one was found to be transparent. I don't know how many they tested altogether. They did use a loudspeaker load. I've done the same thing many years ago, and also found obvious unexpected differences. My series testing was never blind which makes it even less credible.
The totally transparent amp which happened to be in the first two I tried was a Spectral. I was using ESL's which are an odd load especially in the upper octaves for amps. The Spectral sounded the same as a short piece of interconnect. I then believed other quality SS amps would be able to accomplish the same thing. They could not. I suspect it was variation in the upper two octaves, but didn't pursue that enough to find out. I also was younger then and my hearing was good to about 18 khz.
The Spectral had 1 mhz bandwidth. The other amps that were about transparent also had good bandwidth. 200 khz or so. Those with only 50 khz sounded different. But the difference sounded like much more than that. Of course the Spectral was designed for use on Quad ESL63s which is what I was using. So was it bandwidth, or just the amp was designed to work as intended for the speaker I was using while others were not?
Considering switching amps have filters and such at the upper end, it wouldn't be surprising if perhaps those interacted in slightly audible ways involving FR with actual loudspeaker loads.
Stereophile's test of the excellent Benchmark shows with their simulated loudspeaker load enough variation in frequency response it borders on audibility even down around 2 khz. It is about the only result not near theoretical perfection. Also that amp curtails response in the treble into lower impedance loads if the treble impedance dips to 2 ohms. I would imagine it would sound less than transparent for young listeners on my Soundlabs which are below 2 ohms in the treble. The Soundlabs are not a typical load of course unless that is what you use for listening.
Stereophile's test of the excellent Benchmark shows with their simulated loudspeaker load enough variation in frequency response it borders on audibility even down around 2 khz. It is about the only result not near theoretical perfection. Also that amp curtails response in the treble into lower impedance loads if the treble impedance dips to 2 ohms. I would imagine it would sound less than transparent for young listeners on my Soundlabs which are below 2 ohms in the treble. The Soundlabs are not a typical load of course unless that is what you use for listening.
Jus to add info that might be interesting: from what I know THX Ultra amp standard requires amp not to clip with current in any power/frequency condition but at the same time speaker is required not to go below 3.5 ohms with impedance.
I'm drunk now so can't reply properly but , reading these things ( Swedish AES and Alans ideas plus recognising your post) leaves me in a state of bewilderment as the mantra of so-called objectivists has seemed always to be ' modern amp technology is transparent'I don't know what to think either. I would remind that usually measurements of amps are with resistive loads and not with real speakers.
I know I've mentioned it before, but the Swedish AES results of series amp testing are interesting. They did that blind and only one was found to be transparent. I don't know how many they tested altogether. They did use a loudspeaker load. I've done the same thing many years ago, and also found obvious unexpected differences. My series testing was never blind which makes it even less credible.
The totally transparent amp which happened to be in the first two I tried was a Spectral. I was using ESL's which are an odd load especially in the upper octaves for amps. The Spectral sounded the same as a short piece of interconnect. I then believed other quality SS amps would be able to accomplish the same thing. They could not. I suspect it was variation in the upper two octaves, but didn't pursue that enough to find out. I also was younger then and my hearing was good to about 18 khz.
The Spectral had 1 mhz bandwidth. The other amps that were about transparent also had good bandwidth. 200 khz or so. Those with only 50 khz sounded different. But the difference sounded like much more than that. Of course the Spectral was designed for use on Quad ESL63s which is what I was using. So was it bandwidth, or just the amp was designed to work as intended for the speaker I was using while others were not?
Considering switching amps have filters and such at the upper end, it wouldn't be surprising if perhaps those interacted in slightly audible ways involving FR with actual loudspeaker loads.
Stereophile's test of the excellent Benchmark shows with their simulated loudspeaker load enough variation in frequency response it borders on audibility even down around 2 khz. It is about the only result not near theoretical perfection. Also that amp curtails response in the treble into lower impedance loads if the treble impedance dips to 2 ohms. I would imagine it would sound less than transparent for young listeners on my Soundlabs which are below 2 ohms in the treble. The Soundlabs are not a typical load of course unless that is what you use for listening.
So where's the truth .
I have voltage level-matched the ATI AT4000 and AT522NC and compared them single-blind and they were distinguishable.
Contrary to class-d reports form others, I found the NC accentuated the highs. It was not "dark".
It seems reasonable the completely different amplifier architectures could sound different.
The perfect measurement would compare the amplifier input to the output driving a set of representatbie reactive loads.
Differences in timing and amplitude are errors.
- Rich
Contrary to class-d reports form others, I found the NC accentuated the highs. It was not "dark".
It seems reasonable the completely different amplifier architectures could sound different.
The perfect measurement would compare the amplifier input to the output driving a set of representatbie reactive loads.
Differences in timing and amplitude are errors.
- Rich
Well he lives in auz , iv been in bars there where folks fly in for a drink so if he can't keep his Mrs away from his side skirt he's not worth listening to in the first place.
Yes and no. Expectation bias works both ways. If you believe that new ultra spec'd amp should sound better, it will.
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Said Epimenides the Cretan*, if memory serves.
________
* not Cretin
Well, he was right then.
Blumlein 88
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I think not all amps are transparent with all speakers. Worse it may mostly be down to FR. Not distortion or noise levels.
D
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Purely subjective, was never really happy with my nCore monoblocks. Loaned a Norma integrated amp to compare. Sold my nCore’s.
Norma: Extreme low noise, high speed schematic topology and wide band ( >2 MHz ).
What was the procedure to determine that only one amp is transparent? Wouldn't you need to find at least two which sound the same and use that as the standard for transparency?
Blumlein 88
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Yes and no.
In case A you have source>power amp>speaker.
In case B you have source>power amp>loudspeaker load>resistors to drop voltage>power amp>speaker.
In essence you were comparing an interconnect to the sound of a power amp and loudspeaker load.
Even if the power amp playing your speaker was less than transparent, it would be possible the additional amp in the circuit altered the end result. So yes the power amp on the speaker could be so degraded it wouldn't show problems in the power amp under test. You can reverse positions of the amps to get a handle on that. If the speaker power amp and the test amp swap positions, you might find one amp transparent in the test and another not. Which is what happened.
Then if you test several power amps you could start using only those being transparent or closest to it to up the overall transparency level of your test.
In my initial case, I used the Spectral as DUT. It was exactly the same as wire. I swapped positions of the amp. The other amp was clearly colored vs wire. I tested other amps. Some were odd. One amp had a grainy character. Combining it with a tube amp gave a strange smoothness of tubes with grain riding on it. Neither amp was transparent. I got lucky in having a transparent amp on my first try. Even without that by testing multiple amps you could move toward those most transparent and get the total test closer to complete transparency. What I found in practice was with almost any amp powering the actual speakers you could hear whether or not the amp under test was like wire or different than wire.
NOTE: In those famous Richard Clark amplifier challenges where you could win $10k, he specified the amps have identical frequency response to 10 khz or he would equalize one or the other to make it so. No one ever earned the $10k.
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Hi Lars,
I read your comment from 4 years ago on the pinkfishmedia site as well, and the question you left unanswered was what made the difference to you?
Is it a "sound", or more something like the mosfets power reserve, or does the high bandwidth do anything special for you?
As you've compared it with several other amps among which a respected Hegel series, I'd love to know your thoughts.