Benchmark AHB2 or Class D (GaN FET)

I heard it pushing Martin Logan panels hard. Not impressed. The room was probably a factor but I get better sound at home with ICEpower driving Acoustats.

Not the last time that dopes think demo means LOUD. The amp seemed to square it off.

I would add the Orchard Audio Starkrimson Ultra to the class D amps to try list.  it’s a GaN FET amp.  I’ve heard great reviews for the AHB2 but haven’t actually heard one yet.  What speakers are you going to run them with?  Do you need more power than what the AHB2 puts out?

Nothing new here. THX AAA is just a variation of feed-forward error correction. Peter Walker (Quad) used this method in 1976 with the 405 amp. Later the 306/606 and other Quad amps used feed-forward successfully. 

@nymarty my speakers are Acoustic Zen Crescendo II.

They are nominally 6 ohms and about 90dB sensitivity.

Gold Note PA-10 GaN FET class A/D power amplifiers and they are truly balanced and are bridgeable. Reviews are all positive and I have auditioned these with both tube and SS preamplifiers and they are Italian marvels. Outstanding value and sound. 

Ciao 

I have owned the AHB2 stereo and monos. I love the crystal-clear sound of the AHB2. It is actually my favorite sounding amp. However, I sold them to get am amp with much more power, CODA #16. Overall, I like the CODA #16 better.

Here is a great description of how the AHB2 sounds. Totally agree with this post.

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

Currently, I also own a modded Peachtree GAN1 "amp". The mods took it to spectacular levels. However, it is a PIA to use. So, I am going to use the GAN1 for headphones and get another amp for the Yamaha NS5000 speakers. The GAN1 is currently driving the NS5000 and it sounds very good. Just a PIA to use.

If you do not have a very hard to drive speaker, then you may like the AHB2. I am thinking about it for the NS5000.

I owned an AHB2 for about 7 months and I just sold it about a month ago. I used it for headphones and I tried it on my speakers as well.  It was ok but not my cup of tea so that was the reason I sold it.  It was quiet and it provided a black background but it was never engaging.  I tried it with 2 tube preamps, McIntosh C2600 and Linear Tube Audio reference Microzotl preamp, and one solid state preamp, Holo Serene KTE.  For headphones, I like my 4 dedicated headphone amps better (Woo WA23, Auris Nirvana, Enleum 23R and Holo Bliss KTE).  For my Klipsch Cornwall IV speakers, I like my First Watt F7 much better.  I didn't try the AHB2 on my other speakers, Harbeth M40.1 or Sterling Broadcast LS3/6.

If I were in the market for a 100w/Ch solid state amp, I would strongly consider the Atmasphere class D mono blocks that I heard at Axpona.   I've never liked class D amps in the past but those mono blocks sounded great on the Fritz speakers. 

Because an amp uses GaNfets does not mean it is the cat's meow.  The Purifi module and now the sonically better and more powerful HIGH POWERED Purifi modules sound really great......and also Hypex has released its Nilai amps and preamps (available as DIY or assembled).  This is Hypex's best sounding module.....even better than the just released NCX500.  And these Purifi amps and Nilai amps are under $2K for a stereo amp ($1379 for a Nilai stereo amp kit....super easy to build) and just over 2K for mono blocks (over 200 watts a channel into 8 ohms).....less than half of Atmasphere.  And you can have them modded, as well, for even better sound.  Check out VTV Audio.....they sell them both.....along with the all digital amp:....the VTV D300 (300 watts a channel0 stereo amp....what I am using right now).  Orchard Audio also makes great class D amps that do use Gan fets....starting at $2650 for a basic stereo amp....

I don’t see any mention of GaNfets being used in the Gold Note P10.......can you show me where it states that? In the ASR review it mentions Mosfets.

Here is some info on the latest Hypex designs:

https://www.youtube.com/watch?v=B1exMwmlvRg&t=330s

From this page on the Gold Note PA-10 mono blocks it states it's their first design to use GaN FETS but I can't say for certain whether other Gold Note models use them as of yet. 

A quick look at Gold Note's site doesn't even mention the use of GaN FETS in the PA-10, let alone any other model.

All the best,
Nonoise

I had a set of Benchmark run in mono configuration.  I simply could not get them to sound great in my system and had to sell them.  

They had a predominant midrange forward character where the midrange was so much louder than other frequencies.  It was clear and dynamic, almost too dynamic.   I too have 90db sensitive floorstanders like you and cannot recommend the Benchmarks.  

I have an Orchard Audio Starkrimson on order as part of the tour and am looking forward to it.  

In the mean time a Parasound a21+ is sounding pretty decent.  

Here you go @ricevs ​​​​@nonoise . Almost every review mentions it so they must know more than us and GN is simply play their cards close to their chest?

I do know this they sound great and better than most if not all the Class D that I have listened to. 

https://positive-feedback.com/reviews/hardware-reviews/gold-note-pa-10-amplifiers/

https://www.hifipig.com/gold-note-pa-10-power-amplifier/

https://darko.audio/2020/07/brawn-and-brains-gold-notes-pa-10-power-amplifier/

Found another guys where the gents at 6 moons did speak to the designer.

Page 2 they confirm GaN being used in the PA-10 and that it is not Class D. 
Enjoy.

https://6moons.com/audioreview_articles/goldnote13/2/

That's the same one I linked to in my post. Like the article quotes, the PA-10 is the only one to use them.

All the best,
Nonoise

@nonoise yes, and I was also addressing @ricevs comment. Gold Note also makes Tube Amplifiers and like other fine Italian marquis they perform and look the part IMHO.  If you have a chance to listen to the complete line they will not disappoint in regards to integrated amplifiers, stereo amplifiers and mono-blocks.

I’ve not heard the latest iterations of class D so cannot comment on these amps, but I recently took delivery of a Benchmark amp, and it is incredibly quiet, dynamic, and clean thru 93db Verity Leonore speakers.  I am streaming with a less than reference setup in my second system and yet, the amp is a revelation and surprise.  Tracy Thorn’s voice on the 30-year recording of Amplified Heart gave me goose bumps right out of the box.  I can understand the observation that midrange or voices may seem forward, but concert mixes can have the vocalist forward if you’re center row, close in and studio mix pull it this way often as well.  This amp just doesn’t add much, if any sound of its own.

Tubes are what I have listened to for decades – Shindo in particular, coupled with very nice front-end components.  The Benchmark, with a completely different presentation is thoroughly enjoyable.  I’ll now need to upgrade my DAC and streamer to keep up with the Benchmark.  The Benchmark makes me think of an audio mag cover a few years ago, it showed a high-end, well regarded tube amp and a SS state one and said something to the effect that if one is right, then the other must be wrong.  In fact, they were both great amps.

Hi Fi Critic reviewed the Benchmark and gave it a very low score.They praised the measurements but said it was quite poor at musical communication.I have heard some Class D amps including Purifi ones that sound like that too.Although they also had quite poor imaging too.

Well, the Hi Fi Critic sorta killed this thread.

Benchmarks amplifiers are not Class D. 

I have owned the AHB2 about 5 times during the past 10 years. I think I may have made money on the amps, though that was not the intention.

I have the Peachtree GAN1 that I mentioned in my prior post. I also have the Peachtree GAN400. I was totally satisfied with the GAN400 on my slightly bright Magnepan LRS+.

However, I had negative listening session with my Yamaha NS5000 and the CODA #16 in my other system. That session made me miss my cleaner sounding Benchmark AHB2’s which I think would be a nice match for the slightly warm NS5000.

I then paired the slightly warm CODA #16 with the slightly bright LRS+ and that combo was better than the GAN400 with the LRS+. We are talking Class A vs Class D and GAN. The cost is $16K vs $2K.

When I compared the GAN400 with the #16 on the LRS+. I notice that the GAN400 had a bit of hardness on the top compared to the smoother #16. The #16 sounds more full or organic while the GAN400 is a bit drier. Saying all of this, I loved the GAN400 on the LRS+. It is just the #16 is a perfect amp for the LRS+.

The CODA #16 stays with the LRS+. I will likely get a pair of AHB2 monos to try out with the NS5000.

I am returning the GAN400 tomorrow because it is not as good as the AHB2 I am going to try next. The AHB2 and the modded Peachtree GAN1 are more comparable. Though the 200 watts on the GAN1 are not enough for my NS5000 and the GAN1 is a PIA to use.

The HiFI Critic likely likes gear that I think is sheete, so who is correct? No one really.

BTW - I also owned a LSA Voyager GAN 300. I also had that one modded. The PeazchTree GAN amps seem a bit better to me, definitely the modded GAN1. I like the GAN400 more than the LSA Voyager. It seems to bit more powerful. I like the AHB2 over all of them except the modded GAN1 which is in the same class as the AHB2, but warmer.

I’ve had the AHB2, the Atmasphere and the AGD Audions, and I greatly preferred the Audions.  I found the AHB2 to be non engaging and the Atmasphere to be a little harsh in the upper frequencies.  In contrast, the AGD was neutral, fast, black background, delicate with great imaging.  Definitely keepers!  I hope that other ganfets catch up!