Dust Settled Consensus- is the Benchmark AHB2 an Audiophile Amplifier?

For me it has. It is the only amp I have left after the following amps came and went in the last 2 years:

- CODA #8

- Parasound A21+

- NAD M22 V2

- D-Sonic M3a 800s

- CODA CSiB integrated (from 2019 not latest)

- LSA Voyager 350 GAN (modified by EVS much better than stock)

- KRELL K-300i integrated

- KRELL Duo 175XD

I use the AHB2 monos in my office with the Benchmark LA4 preamp and a warmish Musetec 005 DAC. I also have a tube Magnum Dynalab 108T tuner that also sounds great with the clean Benchmark combo. I have the Benchmark DAC3B but switched it out for the warmer Musetec 005 DAC. I use the DAC3B instead with a tube headphone amp.

I sold the KRELL XD amps because I continued to upgrade up the line. I will be buying a more powerful KRELL XD amp for my future Livingroom system (when the amp is released).

Another amp that I would consider with the AHB2 is the CODA #16. It has the same crystal-clear clarity of the AHB2 amps. The AHB2, KRELL XD, and the CODA #16 are my fav amps. I am no longer searching for amps. 

BTW - I listen all day and late into the night with my office system. No fatigue, just enjoyment.

From my experience the AHB2 should not be used with speakers that go into 2 Ohm and I feel it does not provide thunderous power with speakers it even matches well with. When I demoed the Magico A3 speaker I took along a single AHB2 stereo amp and it was awful with the A3. A Mark Levinson amp and ML 585 integrated was so much better. I attributed the AHB2's poor showing to a lack of power. 

Running the amps in mono are actually not rated for 2 Ohm while the single stereo is officially rated for continuous operation in 2 Ohm. I had monos on my hard to drive Thiel CS3.7 and it was lacking grunt. The CODA #8 and the KRELL XD line were so much better in the thunder department. The D-Sonic also had way more grunt than the AHB2 though I thought the AHB2 was the cleanest and nicest sounding on the Thiel (minus the grunt on certain music).

What I use the AHB2 monos today is really a killer setup. I have the KEF LS50 Meta + KEF KC62 sub in my small office powered by the AHB2s. I had planned on buying the Yamaha NS3000 monitors (almost $10K) from Canada but the AHB2 and KEF LS50 Meta sounded so good I decided to save my money. 

I am done in the office system. 

My Livingroom system which will be rather costly will either use the Benchmark LA4 preamp or Holo Serene preamp (both ASR wet dreams). 

The following post on ASR about the AHB2 was so right on the money and so well written.

Review and Measurements of Benchmark AHB2 Amp | Page 5 | Audio Science Review (ASR) Forum

@decooney The Benchmark DAC3B | RAAL-Requisite VM-1a tube headphone amp | RAAL-Requisite SR1a earphones or CA-1a headphones are an incredible combo. The DA3B is magic with this headphone amp. Other warmer DACs, like my Musetec 005 DAC, do not match well with the 7 tubes in this amazing headphone amp.

I am trying to recreate the same level of sound with a future 2-channel system in a decent sized room. It is going to cost me some money to do so but the above sound is the benchmark that needs to be surpassed, and I do not mean the AHB2.

My office system with the KEF LS50 meta and the AHB2 stuff cannot approach the level of sound as the RAAL VM-1a. Even if I spent $100K more on gear for my office system. Room acoustics dictate that it will not sound as good as the SR1a earphones. Now in a bigger room I believe I can get better than the VM-1a + SR1a.

Stereophile will be reviewing the VM-1a and SR1a and likely going to say the same as me.

• AHB2 monos | LA4 preamp | SR1a earphone | RAAL amp adapter box | Musetec 005 DAC is very good. Though not as good as the VM-1a + Benchmark DAC3B.
• AHB2 monos | LA4 preamp | SR1a earphone | RAAL amp adapter box | Benchmark DAC3B is awful.

@ricevs I do remember reading about this GAN 1 amp now. Now that you have compared it to the Voyager, I will believe what you say. Ric's mod of the Voyager was great. It was almost like the AHB2 for my ears, with more power than the stereo AHB2. Since I had the AHB2 I decided to sell the Voyager.

BTW - the AHB2 monos (what I use) are close to 400 watts (or maybe 500) without increased distortion as you usually see when you switch a stereo amp to mono.

@kijanki I discussed with John Siau (AHB2 designer) and also Tom Thiel (Jim’s brother) about the AHB2 monos on the CS3.7’s. I do not think you can find more knowledgeable folks on the amp and speakers. Anyways, they said it would work and Tom liked the AHB2 on the CS3.7 (he uses the AHB2 in his work). I also liked the AHb2 on the CS3.7. It really had the best silky-smooth sound. My observations are exactly like that great post on ASR that I linked above.

Review and Measurements of Benchmark AHB2 Amp | Page 5 | Audio Science Review (ASR) Forum

However, I disagree with John Siau and Tom Thiel believing the AHB2 monos are a proper match for the CS3.7. For music like Santana’s Soul Sacrifice (Woodstock) the CS3.7 sounded better with a more capable 2 Ohm amp.

@ricevs I had a Peachtree NOVA 150 for a few years and at one time I tested out the preamp section and the amp sections separately. The preamp section was not that good (amp was not bad). Now this is not the same as the GAN amp you referenced but I cannot get my mind to think Peachtree is great after my experience with the NOVA 150.

BTW - what is an audiophile amp? A lot of amps that people rave about are not ones I could ever live with. Nice to hear sometimes but not to listen to every day like I do. For my ears, the AHB2’s are reference level gear, but with some limitations. Like all gear.

@ricevs I just sold a KRELL Duo 175XD (175-watt Class A) amp that I know will not be ideal for the Blades in my Livingroom. The room is rather open with a 25+ foot ceiling. The AHB2 monos which have more power than that will also not be really powerful enough with the Blade. Contrary to the Stereophile review that used the AHB2 monos with the Blade 2 Meta. 

I am getting a big boat anchor Class A amp for the Blades because these speakers will use that power and current to make better sound than the AHB2 or the 175-watt Class A amp I just sold.

 I am looking at a KRELL Dou 300XD, KRELL Duo 375XD mono, or KRELL KSA i400. The KRELL XD line is closer to the PASS in that it is warmer than the AHB2. No thoughts of Seppuku on my part. I can have both AHB2 and KRELL and enjoy both.

I liked the AHB2 very much when I got it. It was very clear, clean and noiseless, but when the Coda 16 arrived it made the AHB2 sound thin, anemic and lacking weight. I now have tube mono blocks so maybe I like distortion.

I totally agree with that comment with certain speakers. In fact, I bought lancelocks AHB2. The CODA #16 sound a lot like the AHB2 on top but it has grunt. That 150 watt CODA #16 is more powerful sounding than my 400 or 500 watt AHB2 monos. Though with a proper speaker match the AHB2 is great.

That comment about the AHB2 owners never hearing or owned $10K+ amps is not true in my case or in the case of some folks I have conversed with online.

The great thing about the AHB2 is that it should not be an amp that is a mystery. It is rather low cost and with a 30-day, home trial. If it does not work for you then you move on.

The guy that bought my KRELL Duo 175XD (a $11K amp) had the AHB2 with Harbeth speakers (a great pairing in my opinion). He was amazed at what he heard. However, after a couple of weeks he felt he was listening to the amp and not the music. It was too revealing for him. He easily sold the AHB2 and bought my KRELL. He loves my KRELL so far. Though I would say the KRELL is sufficiently revealing and is just much warmer.

When I heard Harbeth with a top end Luxman stack (m900u/c900u) I enjoyed it, but I was thinking this would sound great with my AHB2's.

@radioheadokplayer The HPA4 + DAC3B + Meze Empy is also a great combo. I had that for a while and really enjoyed it.