Benchmark AHB2 Amplifier, opinions and competition

Wwoodrum,

Thanks for the feedback.  Right now, after a few days break in, I’m loving the amp. I actually already do use high end cables.
 I get my old amp back from repair tomorrow.  I almost don’t want to hear it.  But I probably will just to confirm how much better the Benchmark is.

@rvpiano - I've had my AHB2 for three years and purchased a DAC 3 HGC to go with it last year. The amp replaced a Bryston integrated; there was no question but that I was going to keep it after a few days break-in and a head-to-head comparison using a DAC as the source for both. I am still very happy with it. Add some high-end cables (the Benchmark folks don't believe in that stuff) and find out how accurate and resolving it really is!

Kijanki,

I read the entire thread.
 Very interesting discussion.

rvpiano, read this thread:

https://forum.audiogon.com/discussions/benchmark-ahb2-amplifier-what-to-expect/post?postid=1508770

I hardly put a lot of weight into the opinions of those fanboys.

Here's something to ponder over.

Subjective shootout, Schiit Vidar $700 v Benchmark AHB2 $3000
Quick read looks like they prefer the sound of the Vidar more than the 4 x!!!!! more expensive AHB2
https://www.superbestaudiofriends.org/index.php?threads/benchmark-ahb2-impressions-vs-vidar.5131/

Cheers George

@rvpiano 
 
The music fairies sprinkled their magic. 

Mzkmxcv,

All of a sudden everything came together.  I guess the amp broke in, or the weather, or something, but the sound is full, rich, powerful and detailed!
And the sensitivity switch is in the middle as recommended.
 I couldn’t be happier, or more surprised!

 It’s a keeper.

@rvpiano

Blame the music studios not the gear 😬.

Good gear just shows which songs were handled with care, which ones wanted to win the “loudness war”, and which ones were simply not handled with any care.

If after a few days it still doesn’t sound good, try alter speaker placement (reduce toe-in for instance), and see if that helps. If not, then return it.

@douglas_schroeder  Ever consider making a youtube video of your cable format? 

The more I listen to the Benchmark, I’m hearing that the reviews are accurate: it has laser-like precision, but is not forgiving on mediocre recordings. As most recordings are not audiophile, that becomes a problem.  I have thousands of CDs and records.  I want to be able to listen to them without gritting my teeth.
 I’ll have to see how the amp breaks in before I decide whether or not to keep it.

@jetter

They might have stated in-room sensitivty (Klipsch almost always does this for instance, but they are even worse and use corner (2-wall) loading, so +6dB).

Bass-limited speakers usually get +2dB while almost full-range speakers get +3dB.

So, if they stated 89dB, it might be 87dB in actuality, or even 83dB if it were a Klipsch speaker.

Also, that’s at 6ohm, which takes in 1.335x the wattage, so my stated 25W which was for 8ohm nominal is thus >33W, not to mention if their minimum impedance take up a large bandwidth.

100W (8ohm) is +3dB vs 50W (8ohm); 
https://www.audiocheck.net/blindtests_level.php?lvl=3
It’s a good difference in volume.

You also don’t know if it’s just a better amp in general and that’s also why it sounds better to you.

Go to the cable forum and read up on the thread that bears my name, regarding the Schroeder Method of IC placement. I have been doing this with the Benchmark Amps in Mono and they are nothing short of stunning. 

mzkmxcv, …."Even 25W is good enough for most setups (if you’re speakers are 84dB sensitive and you sit 20ft away, that’s a different story)."

This has not been my experience, my speakers are rated at 89db, 6 ohm nominal, although I suspect they are a little less efficient than this would indicate.  They only really came alive after I started using a 100 watt+ per side amp.  Oh they played using 35W tube and 50 watt SS, but they sang with the greater power.

Try the Job 225. Lots of info and reviews online.

As I’ve been listening to the amp and experimenting, the richest sound I get is with the sensitivity switch in the uppermost position with the highest gain.
The technician at Benchmark suggested the middle position, but on my set the upper position sounds best.

@rvpiano 
 
Yeah, 100W into 8ohm doesn’t seem like a lot for $3000, but people overestimate how much wattage they need. It also doesn’t help when you have companies like Sim/Moon who sell a monoblock amp that delivers 888W (for ~$120,000), the funny thing is that it has more distortion than the Benchmark. 
 
Even 25W is good enough for most setups (if you’re speakers are 84dB sensitive and you sit 20ft away, that’s a different story).

I’m not bridging.  I only intend to use one amp.
It seems plenty powerful with my speakers.

rvpiano OP


Nice amp, if you want to hear them at their best, don't bridge "if there's no need to", as all you'll gain is watts, everything else takes a hit.

And if you have two of them better to run them in stereo mode and vertically bi-amped, instead of bridging.
http://www.av2day.com/wp-content/uploads/2014/05/biamp2.jpg

Cheers George

I find better bass is a common observation with Benchmark products. It isn’t simply more bass as in fact their bass response is flat. Just better definition of pitch and timbre - you hear more detail in the bass and better separation of instruments at those frequencies.

I upgraded to AHB2 from class D Rowland 102.  I had similar impressions, but what really surprised me was bass extension.  I started hearing lowest bass notes more pronounced.  How different could be 5Hz@-3db (Rowland) vs 0.1Hz@-3dB (Benchmark) when the lowest bass note is 41Hz ?

Just got the Benchmark amp.  Preliminary impressions: cleaner than my old amp, wider sound stage, better definition, better bass.  I’m sure has to break in yet.  Just turned it on.  But, very promising so far. 

The Benchmark is tough to beat when it comes to resolution, transparency, and neutrality.  Especially at the price point.

Yes modding voids the warranty. You would needc to contact him and he could explain the mods. No components are changed and they are all passive. Made a nice difference in mine and I would do it again.

I hope you like them. They are clean sounding and transparent but if you are looking for warmth they are probably not going to meet that requirement.

Reason i shot first is that I needed an amp quickly, as a stop gap, because my very old one broke down, and I was tired of waiting for repair.
Was going stir crazy with new speakers and nothing to play them with.
Really just auditioning the Benchmark.  If I love it, I’ll keep it.  Otherwise, have 60 days to try it out.

+1 mrdecibel
Shoot first ask questions later?

rv, If you were looking for opinions on the amp, why order it prior to doing so ? Lot of good reviews, but a lot of good amps at that price range. What I read was the Benchmark is quite a bit better running in balanced mode. Have not heard one, but believe, based on my readings, it is without question, a very neutral amp. P.S.  Modding the amp will likely eliminate the manufacturers warranty. I would contact Benchmark before you do anything. Enjoy ! MrD.

Flat4,

What did Bob do?

Really enjoying mine. I sent mine to Bob at MyTdss and sweeter and even cleaner now.

Yeah, I run mine bridged. LOL

Just don't bridge it, or we'll have a re-run of the thread from last year. (-;

OP: how is your setup sounding with the new amp?  Let us know when you install it.
A review of the amp was posted by dagogo.com:
https://www.dagogo.com/benchmark-media-systems-ahb2-power-amplifier-review-2/

Thanks to all for the responses.

Kal Rubinson (The King of Multi-Channel Reviewers) uses 3 of these as Monoblocks in his 5.1 system. Has them hooked up to his Audio Research MP-1 Multi Channel Pre-Amp.  High praise indeed!! 

I've read a lot of reviews before I bought AHB2.  Here is summary from "Absolute Sound"

Because accuracy allied to absolutely reliable performance is the goal of all the Benchmarks, they are not products that tend to attract cults or other sorts of starry-eyed enthusiasts, wholly lacking any of the quirks, foibles, idiosyncrasies, sonic flavorings, euphonic distortions, and so on that characterize the objects of most audio cults. Professionals buy Benchmark because they know the products work and are reliable and accurate—indeed, reference caliber. Music lovers buy them because they are neutral and accurate and thus reproduce the tonal character of voices and instruments correctly (and also, I presume, because they are reasonably priced, most musicians, like most other people, being typically not wealthy). But audiophiles? Well, the longer I’m in this racket, the less I sometimes think I understand what audiophiles really want except that a lot of dallying about with components, equipment swapping, and coloration matching seems to be what amuses them. I’m not sure I can in good conscience recommend this amplifier to them as I am not sure they are in search of what it offers: a precision instrument designed to perform the precisely defined task of reproducing music and sound accurately, which it does essentially to perfection. But to anyone else, the AHB2 gets as high, enthusiastic, and confident a thumbs up as my arm is capable of reaching.

This amp has a great clear sound because of the low noise floor. I have not owned another amp that sounded like it. I sold it a few months ago to raise some cash and I am considering buying another AHB2 for a bedroom system (KEF LS50 speakers).

There were some things that bugged me about the amp when I compared it to a Mark Levinson integrated (585). The ML had better ability to make the speakers I was auditioning disappear (Magico A3).

Amps using Hypex should give good competition, such as the ATI AT522NC or AT542NC.


The only downside to the Benchmark is “only” 100W into 8ohm; though I doubt you even need 25W with your setup.