Benchmark AHB2 power amp impressions?


Does anyone have any opinions/info to share about the new Benchmark AHB2 power amp? Do the company's assertions about drastically reducing noise and distortion ring true? Thanks to all.  
ranchhand1
I have the same questions that ranchhand1 has above about the Benchmark Media's assertions about drastically reducing noise and distortion, etc.

The review, by Paul Seydor of the Benchmark Media AHB2 power amplifier ($2,995) in The Absolute Sound (#262), was very interesting.  He gave it a “high, enthusiastic, and confident thumbs up. The product review was interesting and alerted me to a new product that I had not heard of before.  Please note that reviewers, friends, Audiogon, etc. recommenations are interesting BUT I always listen and decide for myself.

Since the Benchmark DAC2 DAC has its own volume control, it means it can be connected direct to the power amplifier (no pre-amp).  The Benchmark AHB2 power amplifier can also be used in stereo or a mono only version for increased power.

I am not in the market for new products since I am very happy with my Bricasti M1 DAC and my Hypex NCore NC400 mono block power amplifiers. However, if I was in the market, I would review the Benchmark AHB2 and the Benchmark DAC2 DAC.   I like the fact that Benchmark products are engineered and manufactured in the USA. Please see:

http://benchmarkmedia.com

I like their transparent audio path and their design looks very good.   Does anyone have any comments, or experience, with the Benchmark AHB2 power amplifier and/or the Benchmark DAC2 DAC?   Thanks.   

I have been using the Benchmark DAC2 now for several years now. I could not be happier with this unit. I use it on my office system as a digital pre-amp. I also use a FM- Tuner with this DAC since it has 2 analog inputs. I have 2 other computer based sources going into the digital inputs of the DAC. All the inputs sound great. I have very good equipment for an office system. The weakest link is not the DAC.

1) KEF LS50 speakers
2) Torus RM15 power
3) Magnum Dynalab tuner
4) Benchmark DAC2
5) Audience speaker cable and  balanced interconnects
6) Parasound  A23 amp
7) Roon and Tidal for FLAC digital music sources

I used to have a BAT VK-42SE pre-amp in this mix with the Benchmark DAC2 serving as a DAC and not a digital pre-amp. The sound was a little fuller with the BAT but I preferred the sound I have now with the DAC2 alone. It sounds realistic and clean.  I sold the BAT. The BAT was a 6K item when It came out and the new replacement for it is a 9K piece. A lot of people may prefer the fuller sounding BAT in the mix.

My goal now for almost 2 years is to get the Benchmark AHB2 amp. Once certain business investments are completed I will jump at getting this amp to replace my Parasound A23.  Cannot spend money on audio at the moment.

I have heard quite a few DACs over the last few years, The best being the Resonessence Labs MIRUS DAC and the PS Audio DirectStream. The DAC2 was not played on the same level equipment (especially amp) as the other 2 so it is not a fair comparison. However, using the DAC2 for years now has not made me wish I had something different. I think it is pretty close in performance to the top 2 DACs I have heard.

Benchmark is based in Syracuse, NY. I have family in that town so I am also happy to support business based there. Especially when I am so happy with their products and email support.


I had a chance to audition the AHB2 in my own system and later on also received the DAC2 to complete the audition (thanks to the local dealer for making this happen).  However this was maybe 9 months ago so please take into account that my observations are largely based on what I can recall.
The AHB2 is a very well built amp and its got a nice heft to it despite its small size, which is plus when moving it around in the rack.  Fit and finish is first class - no complaints there.  Since it was a new unit I gave it some 50 hours of burn in before critical listening
I drove it first with my CAT SL-1 preamp (AHB2 set on mid gain sounded bland so ran it on high gain).  It is indeed a QUIET amp - with the pre on mute, not a sound with my ears to the speakers (bookshelf Green Mountain Audio). To me the sound was very clean - almost too clean.  Abundant micro details and a black background though a little lean overall.  Overall it sound a little sterile for my taste - something like what you might expect to hear in a recording studio monitor I assume (I was reminded a little of my listening session with Genelec studio monitors which had a similar sound signature).  Pace and rhythm was very good, mids were very clean  but the overall presentation lacked something (the emotion?) which to my mind is that critical glue that binds all the elements of the recording and presents it as music.
Next up I drove it directly from the analog outputs of the DAC2 (DAC2 set to 0dB and AHB2 to low gain as is recommended).  This combination felt like a better match (even quieter and with more perceived drive) but the sonic signature didn't change much - and it was still a little lean and that sterility factor persisted - perhaps even more so.
I appreciate all the technology that has gone into making the AHB2 and the small form factor, great finish and substantial 190W @4ohms from a small chassis, But I wan't swayed enough by the sound to pull the trigger to purchase it.  Also, my own sense is that while the amp has three gain options to make it a suitable match for different pre/DACs etc, it was probably mostly conceived as a partner for the DAC2.
YMMV

I just got an AHB2 this past week. After using and moving heavy amps for a long time (Pass, McIntosh, etc) I decided I want a lighter, smaller amp. After reading reviews on the Benchmark, I decided to try it.

I’d echo many of jitterbug’s comments, though I don’t find it ‘sterile’. Perhaps because it’s so quiet and we tend to get used to other ‘noise’ in the music it seems that way, I don’t know.   I’ve been able to hear separation of instruments more clearly than ever before (at least to my auditory memory) and the level of detail is really something.   In familiar recordings I’m also hearing things I don’t recall hearing before. So far it’s been a real pleasure!

I’m using it with a Cambridge 851d as a preamp/dac and my current speakers are Harbeth C7-ES3’s. I currently stream via Apple TV to the Cambridge, and also use an Oppo 93 as a transport.

I plan on moving to a Benchmark DAC-2 HGC shortly as the Cambridge has developed a quite noticeable transformer hum.  


I Have owned a pair of AHB2 as monoblocks for a year, and they replaced a pair of Marantz MA9S2 with no regrets. Yes they are quiet and clear, more so than the Marantz.

It does not sound Sterile to me , but the partnering electronics have to match. In my system the Hegel P30 preamp sounds a little too aggressive on the AHB2, but the Cambridge 851E gives it a happy marriage. 

I have better amps but for the price, size, performance and convenience , the AHB2 is a great buy. I plan to keep them for a long time . 
Benchmark make great products - many of them "giant killers" for a good price. To be honest I don't care for the Marantz sound at all but I know many like the smoother more laid back or "natural" presentation they are known for.
If THD and S/N were all the buzz, we would never have things like tube amps, SETs, etc. where even 3% THD is not far from the norm, as well as s/n < 100dB.
It is no wonder that many audiophiles from the real world (you can find those only on various audio forums such as this one) assess this amp as "too clinical", "no emotion", etc. This is in sharp contrast to assessments of so called professional reviewers. Ask yourself why.
I'll start by asserting the following: neither Revel Ultima Salon 2 nor AHB2 that were used in most professional reviews are exceptional. Yes, you will find many praises for the two. But the MAJORITY of the real world audiophiles have already spoken. Nowadays, many people who bought Salon 2s regret their decision. MANY of them try to sell their speakers in very good condition on agon for less than half of the $22k msrp price, e.g. $10k, but are unable to. The word spread. The speakers were not worth $22k to begin with.
What about AHB2?
I'll answer by asking what about it's frequency range? What about slew rate? Rise time? It is widely known that as far as human ear is concerned both frequency range and slew rate are much more important than THD and other parameters (they are important, but not to the extent these other ones are). Ideally, the frequency range of an amplifier should be in the range 3MHz or more, but definitely more than 1MHz. Thus it is much better to design an amplifier with lower s/n and/or THD, and correspondingly higher frequency range and slew rate / rise time than vice versa. Only then you will get the so called "organic" sound, yet detailed and "you are there", "non fatigue" etc.
@navrsale 

You seem to be an expert. Could you please provide some data on the slew rate etc. of the Benchmark amp?
@navrsale 

AHB2 Slew rate is 16V/uS and rise time at 3.5mS and a bandwidth of 200kHz.

I can't understand why you think a 3 Mega Hz bandwidth is required in an audio amplifier. 

You seem to prefer higher distorting euphonic designs and there is nothing wrong with your taste.

However, some audiophiles are impressed and interested in the market leasing high fidelity that the AHB2 amp offers. Especially the performance at low levels like 1 watt where this amplifier excels just as amazingly as it does bridged at 300+ watts.
@shadorne 

I can't understand why you think a 3 Mega Hz bandwidth is required in an audio amplifier.

Maybe he can hear very high frequencies :)))