Amplifier distortions - what, and how much are audible

[PENG]

John Siau is saying nothing except that amp distortions can rise to a dB level consistent with home appliance noise, when using otherwise excellent equipment. Does anyone here think he meant that the distortion will sound like a washing machine?

The point is, what is the point then? The fact is, we can all hear our washing machines loud and clear anywhere in a small to medium size room/house (say 2000 sq.ft), but we can't hear the Parasound A21+ amp's noise except listening to close to reference level during the quiet to almost completely silent passages such as in between movements in a violin concerto? So, okay he's right in saying what he's saying, but there's not much point saying it when it actually have the outside chance of misleading people, again not someone like you who are obviously very experienced and knowledgeable in the related topics.

Perhaps the best thing to do is audition one of his AHB2 amps and listen for ourselves instead of being so critical of his presentation – a presentation attempt meant for audiophile consumption.

I have to respectfully disagree, audiophiles likely wouldn't care as lots of them, even the majority I would guess, usually just go by what they thought they heard, without thinking much about Oh, I heard the snake hiss that ADTG talked bout, every time there's a momentary peak pushing near 105 dB SPL in the contents I listened to.

Also, I don't think anyone (that is anyone who under the basic related/applicable theories and principles..) need to his AHB2 amp to appreciate how quiet/silent that amp would be when used for even listening to pure tones at well below it's clipping level.

Benchmark’s AHB2 amps hit all the real audio checkboxes, in a small efficient form. If you don’t like what you hear through it, you don’t like the source recording or something in the chain before or after the AHB2 amp.

I am not sure it you think anyone would disagree with you on this lol..

The comparison is amp to amp. The topic is "Amplifier distortions - what, and how much are audible". We are still measuring things that matter less, and avoiding measuring things that matter more.

Totally agreed, I wish there are good ways to measure the audibility of different audible sound quality due to different recording/mastering quality in quantifiable ways, but even in subjective ways would be nice. I don't want them to stop measuring SINAD, but when we are dealing with the kind of amps JS mentioned in the video, the quality of recording/mastering will, imo have much more audible effects as related to enjoyability.

This is getting more interesting than worrying about phase, so I hope you are not ready to revert to "I am done on this topic"

By the way, I too, am a believer in the AHB2 being among the best in terms of transparency, especially if two are used for 2 channel stereo in bridge mode. My own wish is if he would do a better job on slew rate in the upcoming version, I have no doubt the specified slew rate as it is now is more than high enough, but it is far from SOTA, yet it's specified SINAD is definitely SOTA, second or third to may be a few class D amps (based on measurements found on ASR, or probably Stereophile, or SoundStage Hifi too but not sure.

 

[PaulBe]

The point is, what is the point then? The fact is, we can all hear our washing machines loud and clear anywhere in a small to medium size room/house (say 2000 sq.ft), but we can't hear the Parasound A21+ amp's noise except listening to close to reference level during the quiet to almost completely silent passages such as in between movements in a violin concerto? So, okay he's right in saying what he's saying, but there's not much point saying it when it actually have the outside chance of misleading people, again not someone like you who are obviously very experienced and knowledgeable in the related topics.



I have to respectfully disagree, audiophiles likely wouldn't care as lots of them, even the majority I would guess, usually just go by what they thought they heard, without thinking much about Oh, I heard the snake hiss that ADTG talked bout, every time there's a momentary peak pushing near 105 dB SPL in the contents I listened to.

Also, I don't think anyone (that is anyone who under the basic related/applicable theories and principles..) need to his AHB2 amp to appreciate how quiet/silent that amp would be when used for even listening to pure tones at well below it's clipping level.



I am not sure it you think anyone would disagree with you on this lol..




Totally agreed, I wish there are good ways to measure the audibility of different audible sound quality due to different recording/mastering quality in quantifiable ways, but even in subjective ways would be nice. I don't want them to stop measuring SINAD, but when we are dealing with the kind of amps JS mentioned in the video, the quality of recording/mastering will, imo have much more audible effects as related to enjoyability.

This is getting more interesting than worrying about phase, so I hope you are not ready to revert to "I am done on this topic"

By the way, I too, am a believer in the AHB2 being among the best in terms of transparency, especially if two are used for 2 channel stereo in bridge mode. My own wish is if he would do a better job on slew rate in the upcoming version, I have no doubt the specified slew rate as it is now is more than high enough, but it is far from SOTA, yet it's specified SINAD is definitely SOTA, second or third to may be a few class D amps (based on measurements found on ASR, or probably Stereophile, or SoundStage Hifi too but not sure.

This is the part of your post response I would like to address:
"By the way, I too, am a believer in the AHB2 being among the best in terms of transparency, especially if two are used for 2 channel stereo in bridge mode. My own wish is if he would do a better job on slew rate in the upcoming version, I have no doubt the specified slew rate as it is now is more than high enough, but it is far from SOTA, yet it's specified SINAD is definitely SOTA, second or third to may be a few class D amps (based on measurements found on ASR, or probably Stereophile, or SoundStage Hifi too but not sure."

What is special about the AHB2 in bridge mode other than more power? I use one AHB2 for each bi-amped floor speaker - One channel for woof; The other channel for tweet; Bi-amped mono blocks.

What is wrong with the slew rate with the AHB2? It has a bandwidth that exceeds any amp I remember; from the bottom to the top; with perhaps an exception for some Nelson Pass designs. Any band limited class D amp has lower slew rate, though some have incredibly good low frequency response.

Do you have a reference for the upcoming version? I didn't know a new version is being made. Or, are you stating you would like better slew rate in any new version?

When I read reviews in pop audiophile magazines, I read between the lines. IMO it is rare that reviewers really understand what they are writing. Most reviewers are dilettantes.

Terms like SINAD are functional, yet incomplete. I don't have a substitute or addition. Alas, we use what we have.

 

[PENG]

What is special about the AHB2 in bridge mode other than more power? I use one AHB2 for each bi-amped floor speaker - One channel for woof; The other channel for tweet; Bi-amped mono blocks.

Just higher voltage output, I always prefer to have much more headroom that I actually think I need, for the peaks/transients in contents I might listen to.

What is wrong with the slew rate with the AHB2? It has a bandwidth that exceeds any amp I remember; from the bottom to the top; with perhaps an exception for some Nelson Pass designs. Any band limited class D amp has lower slew rate, though some have incredibly good low frequency response.

I did not say or thought there's something wrong. Like headroom, I simply want more, higher in this case.

Do you have a reference for the upcoming version? I didn't know a new version is being made. Or, are you stating you would like better slew rate in any new version.

I am just hoping they are working on a new version, that offers even better specs, knowing that better specs will just be "better relatively speaking", not audibly better. The same goes for distortions, noise, frequency response etc.etc., like DACs, resistor tolerances, better specs typically result in higher costs, why would people like me still want them and willing to pay more would be the question, and John Siau did provide something on that near the end the video.

When I read reviews in pop audiophile magazines, I read between the lines. IMO it is rare that reviewers really understand what they are writing. Most reviewers are dilettantes.

I said something to that effect in the beginning....

Terms like SINAD are functional, yet incomplete. I don't have a substitute or addition. Alas, we use what we have.

I actually would like to see distortions and noise measured separately, but it is easier to measure SINAD, and as you said SINAD is functional, highly functionally imo.

 

[AcuDefTechGuy]

John Siau is saying nothing except that amp distortions can rise to a dB level consistent with home appliance noise, when using otherwise excellent equipment. Does anyone here think he meant that the distortion will sound like a washing machine?

Perhaps the best thing to do is audition one of his AHB2 amps and listen for ourselves instead of being so critical of his presentation – a presentation attempt meant for audiophile consumption.

Benchmark’s AHB2 amps hit all the real audio checkboxes, in a small efficient form. If you don’t like what you hear through it, you don’t like the source recording or something in the chain before or after the AHB2 amp.

The comparison is amp to amp. The topic is "Amplifier distortions - what, and how much are audible". We are still measuring things that matter less, and avoiding measuring things that matter more.

Let’s not even talk about amps for a minute.

If you say a speaker has distortion noise of 40dB and tell people repeatedly that a washer also has a noise of 40dB, many people are going to think this speaker sounds as loud as a washer.

That’s how advertising works. This is what they mean by “misleading”.

 

[PaulBe]

Let’s not even talk about amps for a minute.

If you say a speaker has distortion noise of 40dB and tell people repeatedly that a washer also has a noise of 40dB, many people are going to think this speaker sounds as loud as a washer.

That’s how advertising works.

Perhaps John Siau will develop a more satisfying comparison.

 

[AcuDefTechGuy]

Perhaps John Siau will develop a more satisfying comparison.

All he has to say is, “At 100W this amp can produce a hissing noise of 40dB from the speaker from 1 meter distance if there is no other sound playing at the same time”.

 

[PaulBe]

All he has to say is, “At 100W this amp can produce a hissing noise of 40dB from the speaker from 1 meter distance if there is no other sound playing at the same time”.

Here is Benchmark's contact page:

Contact

Support - Before and After the Sale: Our Technical Support and Engineering teams will work with you to attain the highest level of performance from whichever Benchmark product you decide to purchase. Feel free to contact us at any time with your questions, we are here to provide expert advice...

benchmarkmedia.com

 

[Trell]

Perhaps the best thing to do is audition one of his AHB2 amps and listen for ourselves instead of being so critical of his presentation – a presentation attempt meant for audiophile consumption.

Listen to this amp?

Here is a review with many measurements:

Review and Measurements of Benchmark AHB2 Amp

This is a review and detailed measurements of the Benchmark AHB2 Amplifier using THX technology to reduce distortion. I was going to request one for testing due to membership demand but to my pleasant surprise, the company volunteered to contact me and send not one, but two units! I requested...

www.audiosciencereview.com

 

[PaulBe]

Listen to this amp?

Here is a review with many measurements:

Review and Measurements of Benchmark AHB2 Amp

This is a review and detailed measurements of the Benchmark AHB2 Amplifier using THX technology to reduce distortion. I was going to request one for testing due to membership demand but to my pleasant surprise, the company volunteered to contact me and send not one, but two units! I requested...

www.audiosciencereview.com

I've read it. It's a stellar review. I use 9 Benchmark AHB2's in my whole HT. I listen to them everyday. More accurately, I listen through them everyday. The listening experience far exceeds the review.

 

[AcuDefTechGuy]

I use 9 Benchmark AHB2's in my whole HT.

9 x Ahb2 = about $32,000.

That's just way too much for most people. We're talking about McIntosh and Bryston money here. Most people don't even feel "right" to spend anywhere near that.

Then add another $7K for the Marantz AV10. So your "electronics" is about $40K?

And if room acoustics and speakers/subs are a lot more important than electronics - as they should be - how much did you spend on them? $80K ?

 

[mtrycrafts]

All he has to say is, “At 100W this amp can produce a hissing noise of 40dB from the speaker from 1 meter distance if there is no other sound playing at the same time”.

Otherwise, it might be masked totally or partially.

 

[PaulBe]

9 x Ahb2 = about $32,000.

That's just way too much for most people. We're talking about McIntosh and Bryston money here. Most people don't even feel "right" to spend anywhere near that.

Then add another $7K for the Marantz AV10. So your "electronics" is about $40K?

And if room acoustics and speakers/subs are a lot more important than electronics - as they should be - how much did you spend on them? $80K ?

I spent more than some and less than others. I'm retired. My bills are paid. It's my hobby. You've seen my speakers - Homebuilt 2-way monitors. I've been told by one of the forum 'experts' here that I don't know what I'm doing, so, nothing more to say here... move along... move along...

My neighbor has about $150K sunk into a fishing boat, trailer, and pickup truck. Then there is the cost of the fishing trips. He comes home with about $30 worth of fish. I don't fish. I spend $30 at the fish market, or, go out to a Friday night fish fry.

I know average people who spend thousands of dollars every year on season tickets for their favorite sports teams.

It's kind of silly to discuss amp distortions and complain about the $32K cost of 18 SOTA Benchmark amp channels. One of the other manufacturers amps in the Siau video is $22K for 2 channels. Some cost more. McIntosh and Bryston would cost more than Benchmark.

I see you are an authorized dealer for some very expensive equipment. Equipment more expensive than Benchmark. Equipment I can't afford to buy. Care to explain the conflict between your words and what you do? What exactly are you fishing for?

Edit - Yep. Touched a nerve here too.

 

[AcuDefTechGuy]

Otherwise, it might be masked totally or partially.

At 100dB from 1 meter away, I wouldn't even hear much of anything else other than the extremely loud music.

 

[mtrycrafts]

At 100dB from 1 meter away, I wouldn't even hear much of anything else other than the extremely loud music.

How far away, hopefully not close to ear.

 

[AcuDefTechGuy]

I spent more than some and less than others. I'm retired. My bills are paid. It's my hobby.

My neighbor has about $150K sunk into a fishing boat, trailer, and pickup truck. Then there is the cost of the fishing trips. He comes home with about $30 worth of fish. I don't fish. I spend $30 at the fish market, or go out to a Friday night fish fry.

I know average people who spend thousands of dollars every year on season tickets for their favorite sports teams.

It's kind of silly to discuss amp distortions and complain about the $32K cost of 18 SOTA Benchmark amp channels. One of the other manufacturers amps in the Siau video is $22K for 2 channels. Some cost more. McIntosh and Bryston would cost much more.

I see you are an authorized dealer for some very expensive equipment. Equipment more expensive than Benchmark. Equipment I can't afford to buy. Care to explain the conflict between your words and what you do?

One thing I hate about being a dealer is having to answer questions like that. Like dealers can't just be regular forum members.

I was an AH member like 20 years before I became a "dealer".

I was a moderator for Gene before I became a dealer.

Oh, and my FULL TIME JOB is being a full time hospital pharmacists for 30 years, not being a dealer.

But anyway, being a dealer just means I can sell things that other people WANT. I can sell the KEF Muon, but I don't have to buy them.

I can sell Storm Audio and Bryston, but it doesn't mean I have to buy them. I can sell $100K Sony projectors, but it doesn't mean I have to buy them.

If I were starting over again today, I would just get an AVR and be set for Processor/Amps. I can't hear ANY difference between an $2K AVR vs a $20K amp, so I won't spend the money on expensive amps or AVPs.

So there is absolutely no conflict between my words and my actions. I buy what's best for me. I sell what other people want for them.

I know there's one thing everyone can agree on - we all have to do what makes us happy.

 

[PaulBe]

One thing I hate about being a dealer is having to answer questions like that. Like dealers can't just be regular forum members.

I was an AH member like 20 years before I became a "dealer".

I was a moderator for Gene before I became a dealer.

Oh, and my FULL TIME JOB is being a full time hospital pharmacists for 30 years, not being a dealer.

But anyway, being a dealer just means I can sell things that other people WANT. I can sell the KEF Muon, but I don't have to buy them.

I can sell Storm Audio and Bryston, but it doesn't mean I have to buy them. I can sell $100K Sony projectors, but it doesn't mean I have to buy them.

If I were starting over again today, I would just get an AVR and be set for Processor/Amps. I can't hear ANY difference between an $2K AVR vs a $20K amp, so I won't spend the money on expensive amps or AVPs.

So there is absolutely no conflict between my words and my actions. I buy what's best for me. I sell what other people want for them.

I know there's one thing everyone can agree on - we all have to do what makes us happy.

Your presentation here invites the questions. What exactly are you fishing for?

Concerning selling - I can't sell things I don't believe in or wouldn't use. I'd make a very poor salesman.

Anyway, since you sell a bunch of very expensive audio equipment, I assume you have clients you can get information from. Do you have clients?

I know someone who is a Pharma Rep. Talk about a license to steal money...

Edit - Looks like I touched a nerve... asking questions is a two way street.