Benchmark AHB2 Review (Updated Measurements)

[blueone]

Unfortunately this is impossible as our ears aren't microphones and our brains are not computers. It's surely unwise to choose anything - hi-fi, car, boat, etc just on specs and/or measurements.

We go for a test drive before buying a car or boat and we visit showrooms to listen to hi-fi. If we are impressed, we arrange a home demo and then buy the item in the knowledge it will offer what we want. Although everyone's idea of perfect sound varies a little, we choose what most pleases us - car, boat, amplifier, speakers - otherwise wouldn't we all end up driving identical cars and listening to identical speakers within a price range we can afford? Surely "character" in an important influence on how we like or dislike cars, speakers, etc and this cannot be measured. Measurements have their place but shouldn't be relied on to make a purchasing decision - we need the test drive or home demo or we are likely to be disappointed!

Cars and boats, being complex mechanical devices, are not good analogies. There aren't analogous mechanisms in amplifiers to transmissions, suspensions, steering, brakes, outward visibility, and seat comfort. The only amplifiers with discernible differences in audio performance are poorly designed or malfunctioning. But you persist...

 

[DonH56]

Car analogies for audio are always dicey IMO. E.g. I have always felt that lumbar support and seating position are the most important attributes of my power amplifier.

 

[Hear Here]

You could have used measurements instead of trying all those amps.
Keith

Had I done so, I'd still be listening to AHB2 and never wanting to turn up the volume! It was great to try those amps and the ones bought and rejected were resold without more than a few quid lost or gained.

 

[Purité Audio]

The NAD 33 certainly looks smart, performance wise a bit of a curates egg.

NAD M33 Streaming Amplifier Review

This is a review and detailed measurements of the NAD M33 Streaming Player with Purifi Eigentakt Amplification. It is kindly sent for testing from a member and has a retail cost of US $4,999. The NAD is part of their "Masters" series and has one of the best industrial designs of any audio...

www.audiosciencereview.com

Wheras the AHB2 is exemplary, although obviously just a power amp.

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

Keith

 

[GXAlan]

To @Hear Here ‘s credit, he has 18 ohm speakers which are 107 dB efficient.
Post in thread 'What speakers do you currently own?'
https://audiosciencereview.com/foru...akers-do-you-currently-own.54472/post-1979810

If the AHB2 puts out 44W into 18 ohms, and he is listening 20 feet away, he could run into clipping at 107 dB.

 

[Mnyb]

To @Hear Here ‘s credit, he has 18 ohm speakers which are 107 dB efficient.
Post in thread 'What speakers do you currently own?'
https://audiosciencereview.com/foru...akers-do-you-currently-own.54472/post-1979810

If the AHB2 puts out 44W into 18 ohms, and he is listening 20 feet away, he could run into clipping at 107 dB.

An amp with high voltage swing then .
Bridged AHB2 ? Or some class-D ( like the NAD )

A case where bridging amps would be unproblematic

 

[Geert]

If the AHB2 puts out 44W into 18 ohms, and he is listening 20 feet away, he could run into clipping at 107 dB

If the clipping sounds like a doorbell, it might be the neighbours of the apartment he lives in

 

[GXAlan]

If the clipping sounds like a doorbell, it might be the neighbours of the apartment he lives in

Take a look at the link to his speakers and his listening space. It seems that his neighbors are the ocean and he really isn’t in an ordinary apartment when those 1.7m tall speakers (67”) also look small in that space.

Rather than jumping on anyone with an opinion as mere subjective bias, it is worth considering the edge cases where differences can be heard. A giant room like this certainly makes it more likely that he will run into clipping given the listening distances.

And that’s coming from someone who embraces sighted bias

 

[Kal Rubinson]

Unfortunately this is impossible as our ears aren't microphones and our brains are not computers. It's surely unwise to choose anything - hi-fi, car, boat, etc just on specs and/or measurements.

Sure. OTOH, many of use who chose the AHB2 did so based on the same subjective assessments that you made. FWIW.

 

[Theta]

Buying the AHB2 for me was prompted by rave recommendations from the owner of very costly speakers from the same stable as my own speakers. He had deep pockets and had previously used numerous very costly amps of all types, so (before hearing them and before any worthwhile reviews were released) I bought this amp.

This rash purchase proved both good and bad:

Bad because it sounded so dull and lifeless compared with my previous SETs. It was an amp that never encouraged me to turn up the volume - on the contrary, it sounded little more exciting than "elevator music", even though it may be deadly quiet and accurate elevator music! Kiss of death as far as I'm concerned, whatever the spec says or test instruments say. A pity because it offers a great package on paper, in an attractive case, at a sensible price, with nice features such as adjustable gain - and it subsequently received excellent reviews in places where measurements are as important or even (it sometimes seems) more important than what reaches our ears!

Good because it propelled me into a practical and exhaustive search for a much better sounding amplifier that would genuinely offer as exciting and goosebump-inducing music as the best of my SETs, but without trying to mimic their sound characteristics.

The AHB2 was returned to the dealer after a few months for a greatly appreciated full-value credit note. Over the next many months, I bought (new or used) or borrowed a dozen solid state amps of all persuasions to find one that equalled or exceeded the musical satisfaction of my previous amps. I was not interested in their Class or their measurements - solely in their ability to provide a superb match for my speakers and deliver the most convincing, exciting and natural sounding music I could achieve. However, I was expecting that a Class A may well be the winner and indeed one of these (the excellent Accuphase A-36) was kept for over a year, but in the end, it was a little too "polite" despite its superb construction, features and sound.

Amps from Devialet, Red Wine, Quad, Masterclass Sugden, and Lyngdorf were also quickly eliminated for one reason or another - not necessarily on sound quality grounds.

Mark Levinson, Bakoon, GamuT, Micromega, Valvet and NAD fared better, but the winners on sheer musical enjoyment boiled down to the GamuT D200 Mk III and the recently released NAD M33. Because of the GamuT's bad manners (an alarming thump on powering up or down), it was reluctantly sold to someone with less sensitive speakers. Because the M33 offered superb sound and was so much better value with it's built-in streamer, DAC and (best not engaged) Dirac Live DSP, I went for the NAD M33.

No regrets whatsoever over the 3+ years I've been using this excellent amp, that went on to be awarded Stereophile's Best Amplifier and Best Component of the Year and Editor's Choice. However, it may soon be changed for the new M66 plus a pair of mono amps in all probability - but only if the new combo actually sounds better!

Apologies to owners of the AHB2 (or Sugden, etc) and anyone putting too much faith in measurements but, when all is said and done, it's what things sound like that really matters most. I guess I'll have to take cover having told this tale on this particular forum.

A sensible price for a 100W amp?

 

[Hear Here]

The NAD 33 certainly looks smart, performance wise a bit of a curates egg.

NAD M33 Streaming Amplifier Review

This is a review and detailed measurements of the NAD M33 Streaming Player with Purifi Eigentakt Amplification. It is kindly sent for testing from a member and has a retail cost of US $4,999. The NAD is part of their "Masters" series and has one of the best industrial designs of any audio...

www.audiosciencereview.com

Wheras the AHB2 is exemplary, although obviously just a power amp.

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

Keith

Perhaps not worth taking too seriously, but AHB2 was a finalist but not a winner in Stereophile's 2016 "Best of" awards in 2016, whereas in 2020 they chose the M33 as their Amplification Component of the Year and their overall Component of the Year and also their Editors' Choice - a hat trick that I believe no other product has ever achieved. Thank you Kal - see -

https://www.stereophile.com/content/stereophiles-products-2020

The point I made earlier about reviewers' caveats regarding the AHB2 is typified by the section under Listening in the City on Page 2 of Kal's review -

Benchmark Media Systems AHB2 power amplifier Page 2

These surprising and delicious details were evident from the bass up through the midrange and extreme treble, which nonetheless remained silky and diaphanous. One example was Hans Theessink's voice at the end of the phrase "as I lay sleeping," in "Late Last Night," from his album Call Me (CD...

www.stereophile.com

Other good reviews (not the sort of rubbish you see on Youtube) have revealed similar misgivings, although high praise was generally showered on this amp

I'm pleased to say that my Avantgarde speaker purchase from 2002 was also a Stereophile Loudspeaker of the Year, although I've upgraded from the Uno to the Duo and now the Duo XD in the intervening years. If you have a few minutes to spare, take a look at Robert Deutsch's excellent review, or even just the Conclusions, to see why I was so keen to purchase these speakers (as in fact was RD for his own use) after my disappointment with my previous ATC50 speakers -

Avantgarde Acoustic Uno Series Two loudspeaker Page 5

As it happened, most of my listening was with Cary 2A3SE monoblocks (much beloved by Sam Tellig), which are prototypical SETs. They certainly have the genre's famed midrange magic, with a wonderful liquidity and a sense of space and openness. Although the rated output is only 5Wpc, they played...

www.stereophile.com

I mention Stereophile as this is a review source that pays great (though not overwhelming) attention to measurements of the equipment they thoughtfully review. I bought both my speakers and the M33 after having carefully read their detailed reviews, but unaware of their award accolades - and brief dealer demo of course!

 

[pogo]

You could have used measurements instead of trying all those amps.

It is not so easy to interpret the important measurements correctly. See also here and this is just one of many operating modes/points (@4ohms): Link

 

[kelesh]

Had I done so, I'd still be listening to AHB2 and never wanting to turn up the volume! It was great to try those amps and the ones bought and rejected were resold without more than a few quid lost or gained.

I think changing a dozen amps to match speakers is tackling the issue backwards. I would have kept the AHB2 (a known and verified constant) and changed a dozen speakers, but that's just me. Also, turning up the volume changes the perceived FR (Fletcher-Munson) so it's advisable to stay at roughly the same SPL (whatever your preferred "reference" listening level is). But it's all good if what you ended up with makes you happy.

 

[Julf]

I mention Stereophile as this is a review source that pays great (though not overwhelming) attention to measurements of the equipment they thoughtfully review.

As long as you remember that their source of income is advertising...

 

[Purité Audio]

Perhaps not worth taking too seriously, but AHB2 was a finalist but not a winner in Stereophile's 2016 "Best of" awards in 2016, whereas in 2020 they chose the M33 as their Amplification Component of the Year and their overall Component of the Year and also their Editors' Choice - a hat trick that I believe no other product has ever achieved. Thank you Kal - see -

https://www.stereophile.com/content/stereophiles-products-2020

The point I made earlier about reviewers' caveats regarding the AHB2 is typified by the section under Listening in the City on Page 2 of Kal's review -

Benchmark Media Systems AHB2 power amplifier Page 2

These surprising and delicious details were evident from the bass up through the midrange and extreme treble, which nonetheless remained silky and diaphanous. One example was Hans Theessink's voice at the end of the phrase "as I lay sleeping," in "Late Last Night," from his album Call Me (CD...

www.stereophile.com

Other good reviews (not the sort of rubbish you see on Youtube) have revealed similar misgivings, although high praise was generally showered on this amp

I'm pleased to say that my Avantgarde speaker purchase from 2002 was also a Stereophile Loudspeaker of the Year, although I've upgraded from the Uno to the Duo and now the Duo XD in the intervening years. If you have a few minutes to spare, take a look at Robert Deutsch's excellent review, or even just the Conclusions, to see why I was so keen to purchase these speakers (as in fact was RD for his own use) after my disappointment with my previous ATC50 speakers -

Avantgarde Acoustic Uno Series Two loudspeaker Page 5

As it happened, most of my listening was with Cary 2A3SE monoblocks (much beloved by Sam Tellig), which are prototypical SETs. They certainly have the genre's famed midrange magic, with a wonderful liquidity and a sense of space and openness. Although the rated output is only 5Wpc, they played...

www.stereophile.com

I mention Stereophile as this is a review source that pays great (though not overwhelming) attention to measurements of the equipment they thoughtfully review. I bought both my speakers and the M33 after having carefully read their detailed reviews, but unaware of their award accolades - and brief dealer demo of course!

I am not sure I would place any faith in Stereophile, last year’s ‘Product of the Year ‘ was this,

Audio Note Meishu Tonmeister Phono integrated amplifier Measurements

Sidebar 3: Measurements I performed the measurements of the Audio Note Meishu Phono Tonmeister with my Audio Precision SYS2722 system. The tubes were already installed when I received the review sample. I removed the cover to check for proper installation. All was well. I waited for 30 minutes...

www.stereophile.com

Keith

 

[Hear Here]

As long as you remember that their source of income is advertising...

Very true that their main source of income is advertising, but that advertising revenue would vanish if they lost their readers. It is readers that are more important than advertisers in the long run.

But you're right that we need to read between the lines of any worthwhile review. If there are reservations that the reviewer had found, he will draw out attention to these in a pretty subtle way and we need to recognise these subtleties and interpret them as we think fit - they mustn't be ignored as they may be of greater importance that at first thought.

 

[Hear Here]

I think changing a dozen amps to match speakers is tackling the issue backwards. I would have kept the AHB2 (a known and verified constant) and changed a dozen speakers, but that's just me. Also, turning up the volume changes the perceived FR (Fletcher-Munson) so it's advisable to stay at roughly the same SPL (whatever your preferred "reference" listening level is). But it's all good if what you ended up with makes you happy.

Your suggestion of keeping a dull amp and looking for a suitable speaker to counter this dullness seems bonkers to me! There can't be many less dull speakers than Avantgarde, so it would be a hard job in my case!

I think most of us would agree that the biggest decision in getting any first-class audio system sounding great is to find a speaker that will sound great in the room it will be working in. The type of speaker first and foremost - conventional box, electrostatic, horn, omni, etc. This is simply because speakers vary enormously compared with every other aspect and are so room dependant, that getting this right is paramount. Finding an amp to serve the chosen speaker for best performance is important, but getting it wrong is far less disastrous than getting the speakers wrong. I enjoyed my experimentation with amps and was surprised at just how much they varied with the same speakers. The best ones were very similar to one another, but there were some "duds" that could quickly be resold or returned to the dealer.

There are other advantages in home demo'ing several amps - you can appreciate their features, controls, eccentricities, etc. Also, as several of the amps I auditioned had DACs or streamers built in, it is an opportunity to test and compare these attributes too. For example with streamers, the most important (well perhaps the second most important) aspect is their control app. If this is rubbish (and many are) or available only on an Android (as some are), then show them the door! Perhaps these brands expect their customers to add more hardware and pay a subscription to Roon to overcome their lack of providing a comprehensive streaming package.

 

[Hear Here]

I am not sure I would place any faith in Stereophile, last year’s ‘Product of the Year ‘ was this,

Audio Note Meishu Tonmeister Phono integrated amplifier Measurements

Sidebar 3: Measurements I performed the measurements of the Audio Note Meishu Phono Tonmeister with my Audio Precision SYS2722 system. The tubes were already installed when I received the review sample. I removed the cover to check for proper installation. All was well. I waited for 30 minutes...

www.stereophile.com

Keith

Well this just goes to show that paying too much attention to the Measurement page is misguided! Take a look at the Conclusions at the end of the write up:

"Words fail to express the satisfaction I derived listening to music through this expensive Audio Note integrated amplifier. I've got nothing bad to say about it—except for the air thing, if you care about that. I detected no (other) anomalies, artifacts, sonic peculiarities, or outright shortcomings. The Tonmeister, together with the Audio Note SUT I auditioned it with, took what I hear from my vinyl collection and made it better, portraying each performance as a singular, unique event occurring at a particular time and place, its secrets revealed.

If there's a better integrated amplifier in the world than the Audio Note Meishu Phono 300B Tonmeister, I haven't heard it yet."

I've not bothered to read the whole review as it's not an amp I have any interested in, but if it was, surely those comments are more likely to encourage a serious demo than a few PC screen plots showing what a microphone picks up?

Had I concerned myself with the Measurements page of the Avantgarde Uno's 2002 review, perhaps I wouldn't have bothered to read the extremely detailed and accurate write-up by Robert Deutsch that prompted my purchase, and I'd have missed out on years of musical entertainment listening to those great speakers.

 

[SIY]

If there are reservations that the reviewer had found, he will draw out attention to these in a pretty subtle way and we need to recognise these subtleties and interpret them as we think fit

Trying to count the number of angels that can dance on a pinhead.

 

[RichB]

Your suggestion of keeping a dull amp and looking for a suitable speaker to counter this dullness seems bonkers to me! There can't be many less dull speakers than Avantgarde, so it would be a hard job in my case!

I think most of us would agree that the biggest decision in getting any first-class audio system sounding great is to find a speaker that will sound great in the room it will be working in. The type of speaker first and foremost - conventional box, electrostatic, horn, omni, etc. This is simply because speakers vary enormously compared with every other aspect and are so room dependant, that getting this right is paramount. Finding an amp to serve the chosen speaker for best performance is important, but getting it wrong is far less disastrous than getting the speakers wrong. I enjoyed my experimentation with amps and was surprised at just how much they varied with the same speakers. The best ones were very similar to one another, but there were some "duds" that could quickly be resold or returned to the dealer.

There are other advantages in home demo'ing several amps - you can appreciate their features, controls, eccentricities, etc. Also, as several of the amps I auditioned had DACs or streamers built in, it is an opportunity to test and compare these attributes too. For example with streamers, the most important (well perhaps the second most important) aspect is their control app. If this is rubbish (and many are) or available only on an Android (as some are), then show them the door! Perhaps these brands expect their customers to add more hardware and pay a subscription to Roon to overcome their lack of providing a comprehensive streaming package.

Yikes.

Is there a thread somewhere, where this might be considered informative?

- Rich