My Long List of Amplifiers and My Personal Review of Each!


So I have been in a long journey looking to find the best amplifiers for my martin logan montis. As you know, the match between an amplifier and speakers has to be a good "marriage" and needs to be blend exquisitely. Right now, I think I might have found the best sounding amplifier for martin logan. I have gone through approximately 34-36 amplifiers in the past 12 months. Some of these are:

Bryston ST, SST, SST2 series
NAD M25
PARASOUND HALO
PARASOUND CLASSIC
KRELL TAS
KRELL KAV 500
KRELL CHORUS
ROTEL RMB 1095
CLASSE CT 5300
CLASSE CA 2200
CLASSE CA 5200
MCINTOSH MC 205
CARY AUDIO CINEMA 7
OUTLAW AUDIO 755
LEXICON RX7
PASS LABS XA 30.8
BUTLER AUDIO 5150
ATI SIGNATURE SERIES 6005

With all that said, the amplifiers I mentioned above are the ones that in my opinion are worth mentioning. To make a long story short, there is NO 5 CHANNEL POWER AMP that sounds as good as a 3ch and 2ch amplifier combination. i have done both experiments and the truth is that YOU DO lose details and more channel separation,etc when you select a 5 channel power amplifier of any manufacturer.
My recollection of what each amp sounded like is as follows:

ATI SIGNATURE SERIES 6005 (great power and amazing soundstage. Very low noise floor, BUT this amplifiers NEEDS TO BE cranked up in order to fully enjoy it. If you like listening at low volume levels or somewhat moderate, you are wasting your time here. This amp won’t sound any different than many other brands out there at this volume. The bass is great, good highs although they are a bit bright for my taste)

NAD M25 (very smooth, powerful, but somewhat thin sounding as far as bass goes)
Bryston sst2(detailed, good soundstage, good power, but can be a little forward with certain speakers which could make them ear fatiguing at loud volumes)

Krell (fast sounding, nice bass attack, nice highs, but some detail does get lost with certain speakers)

rotel (good amp for the money, but too bright in my opinion)

cary audio (good sound overall, very musical, but it didn’t have enough oomph)

parasound halo (good detail, great bass, but it still holds back some background detail that i can hear in others)

lexicon (very laid back and smooth. huge power, but if you like more detail or crisper highs, this amp will disappoint you)

McIntosh mc205 (probably the worst multichannel amp given its price point. it was too thin sounding, had detail but lacked bass.

butler audio (good amplifier. very warm and smooth sweet sounding. i think for the money, this is a better amp than the parasound a51)

pass labs (very VERY musical with excellent bass control. You can listen to this for hours and hours without getting ear fatigue. however, it DOES NOT do well in home theater applications if all you have is a 2 channel set up for movies. The midrange gets somewhat "muddy" or very weak sounding that you find yourself trying to turn it up.

classe audio (best amplifier for multi channel applications. i simply COULDNT FIND a better multi channel amplifier PERIOD. IT has amazing smoothness, amazing power and good bass control although i would say krell has much better bass control)

Update: The reviews above were done in January 2015. Below is my newest update as of October 2016:



PS AUDIO BHK 300 MONOBLOCKS: Amazing amps. Tons of detail and really amazing midrange. the bass is amazing too, but the one thing i will say is that those of you with speakers efficiency of 87db and below you will not have all the "loudness" that you may want from time to time. These amps go into protection mode when using a speaker such as the Salon, but only at very loud levels. Maybe 97db and above. If you don’t listen to extreme crazy levels, these amps will please you in every way.

Plinius Odeon 7 channel amp: This is THE BEST multichannel amp i have ever owned. Far , but FAR SUPERIOR to any other multichannel amp i have owned. In my opinion it destroyed all of the multichannel amps i mentioned above and below. The Odeon is an amp that is in a different tier group and it is in a league of its own. Amazing bass, treble and it made my center channel sound more articulate than ever before. The voices where never scrambled with the action scenes. It just separated everything very nicely.

Theta Dreadnaught D: Good detailed amp. Looks very elegant, has a pleasant sound, but i found it a tad too bright for my taste. I thought it was also somewhat "thin" sounding lacking body to the music. could be that it is because it is class d?

Krell Duo 300: Good amp. Nice and detailed with enough power to handle most speakers out there. I found that it does have a very nice "3d" sound through my electrostatics. Nothing to fault here on this amp.
Mark Levinson 532H: Great 2 channel amp. Lots of detail, amazing midrange which is what Mark Levinson is known for. It sounds very holographic and will please those of you looking for more detail and a better midrange. As far as bass, it is there, but it is not going to give you the slam of a pass labs 350.5 or JC1s for example. It is great for those that appreciate classical music, instrumental, etc, but not those of you who love tons of deep bass.

 It is articulate sounding too
Krell 7200: Plenty of detail and enough power for most people. i found that my rear speakers contained more information after installed this amp. One thing that i hated is that you must use xlr cables with this amp or else you lose most of its sound performance when using RCA’s.

Krell 402e: Great amp. Very powerful and will handle any speaker you wish. Power is incredible and with great detail. That said, i didn’t get all the bass that most reviewers mentioned. I thought it was "ok" in regards to bass. It was there, but it didn’t slam me to my listening chair.

Bryston 4B3: Good amp with a complete sound. I think this amp is more laid back than the SST2 version. I think those of you who found the SST2 version of this amp a little too forward with your speakers will definitely benefit from this amp’s warmth. Bryston has gone towards the "warm" side in my opinion with their new SST3 series. As always, they are built like tanks. I wouldn’t call this amp tube-like, but rather closer to what the classe audio delta 2 series sound like which is on the warm side of things.

Parasound JC1s: Good powerful amps. Amazing low end punch (far superior bass than the 402e). This amp is the amp that i consider complete from top to bottom in regards to sound. Nothing is lacking other than perhaps a nicer chassis. Parasound needs to rework their external appearance when they introduce new amps. This amp would sell much more if it had a revised external appearance because the sound is a great bang for the money. It made my 800 Nautilus scream and slam. Again, amazing low end punch.

Simaudio W7: Good detailed amp. This amp reminds me a lot of the Mark Levinson 532h. Great detail and very articulate. I think this amp will go well with bookshelves that are ported in order to compensate for what it lacks when it comes to the bass. That doesn’t mean it has no bass, but when it is no Parasound JC1 either.
Pass labs 350.5: Wow, where do i begin? maybe my first time around with the xa30.8 wasn’t as special as it was with this monster 350.5. It is just SPECTACULAR sounding with my electrostatics. The bass was THE BEST BASS i have ever heard from ANY amp period. The only amp that comes close would be the jC1s. It made me check my settings to make sure the bass was not boosted and kept making my jaw drop each time i heard it. It totally destroyed the krell 402e in every regard. The krell sounded too "flat" when compared to this amp. This amp had amazing mirange with great detail up top. In my opinion, this amp is the best bang for the money. i loved this amp so much that i ended up buying the amp that follows below.

Pass labs 250.8: What can i say here. This is THE BEST STEREO AMP i have ever heard. This amp destroys all the amps i have listed above today to include the pass labs 350.5. It is a refined 350.5 amp. It has more 3d sound which is something the 350.5 lacked. It has a level of detail that i really have never experienced before and the bass was amazing as well. I really thought it was the most complete power amplifier i have ever heard HANDS DOWN. To me, this is a benchmark of an amplifier. This is the amp that others should be judged by. NOTHING is lacking and right now it is the #1 amplifier that i have ever owned.

My current amps are Mcintosh MC601s: i decided to give these 601s a try and they don’t disappoint. They have great detail, HUGE soundstage, MASSIVE power and great midrange/highs. The bass is great, but it is no pass labs 250.8 or 350.5. As far as looks, these are the best looking amps i have ever owned. No contest there. i gotta be honest with you all, i never bought mcintosh monos before because i wasn’t really "wowed" by the mc452, but it could have been also because at that time i was using a processor as a preamp which i no longer do. Today, i own the Mcintosh C1100 2 chassis tube preamp which sounds unbelievable. All the amps i just described above have been amps that i auditioned with the C1100 as a preamp. The MC601s sound great without a doubt, but i will say that if you are looking for THE BEST sound for the money, these would not be it. However, Mcintosh remains UNMATCHED when it comes to looks and also resale value. Every other amp above depreciates much faster than Mcintosh.

That said, my future purchase (when i can find a steal of a deal) will be the Pass labs 350.8. I am tempted to make a preliminary statement which is that i feel this amp could be THE BEST stereo amp under 30k dollars. Again, i will be able to say more and confirm once i own it. I hope this update can help you all in your buying decisions!


128x128jays_audio_lab

minorl, thanks for your well considered thoughts.  Since I am not an engineer, I will defer to your expertise.  Just talk to engineers in aerospace, etc. to see whether audio engineers command the intellectual respect you say they do.  Also, there is a crucial difference between the audio engineer who is catering to the subjective whims of many audiophiles who like a certain type of sound but may not value accuracy, and the other engineers like you who are designing for performance and applications based on objective criteria.  If your product performs objectively poorly and causes mass disasters like environmental catastrophies, you get nervous about your job security and long term reputation.  If your product performs at a reasonable level of accuracy but is overpriced, your company will ultimately lose business because the competitive marketplace with many brilliant engineers will encourage value and a reasonable price for the performance obtained.  This is NOT the case with many of the expensive audiophile electronics out there, and even more so with many expensive dynamic speakers out there.  If you value accuracy at a moderate, natural sound level, there is nothing like a decent electrostatic speaker whose technology dates back 100 years and is MUCH cheaper than today's dynamic speakers with their expensive drivers.  Yes, I realize that to get dynamic drivers to perform with clarity approaching an electrostatic, it is expensive and time consuming in the R&D.  The electrostatic principle is simple and inherently superior in low distortion to the dynamic.  One of the tenets of good engineering is designing to a price point, optimizing the performance/price ratio.  Most reputable engineers do this well, but not most audio engineers, despite their claims that they do.  I don't have a test bench, but my hardnosed demands as a value for performance listener and musical expertise lead me to this conclusion. 

charles1dad, continuing this discussion and to acknowledge your points, perhaps I used too broad a brush, but not much.  There are a few audio companies I respect for the value they offer.  For example, Dan Laufman of Emotiva personally may not have the technical level of Dag or Pass, but Emotiva is putting out damn good products for the money.  I almost bought their top amp for $1000 new.  It was absolutely better than MANY high priced gear from other companies, and there is no question that it is one of the top bangs for the buck.  When I returned the Emotiva, it took some time for me to get the refund, because they put it on the test bench thoroughly to make sure it was in top condition.  That's professionalism which I respect.

geoffkait, thanks for your post, more authoritatively supporting my position.
Interested potential students in the field of “audio engineering” perhaps look to sites like below to see what the BA/BS curriculum of audio engineering is :

https://yescollege.com/degrees/bachelors-in-audio-engineering-technology/

These curricula will give you an idea of what graduates of these institutions were taught and how graduates define themselves - few are “hard science” engineers.

Most professional audio engineers don’t represent themselves as having a foundation in electrical or other “hard science” engineering unless they do. Membership in the Audio Engineering Society for example is very eclectic including graduates of certificate programs. The AES is not a member of the American Association of Engineering Societies.

Yes, well, I worked in Aerospace for some time as an Engineer, and I can tell you that Aerospace, is probably one of the most overpriced , exaggerated costs fields (with regards to their final products) out there. 

There is so much fat attached to the end products that you wonder how a hammer costs $600 or billions for an aeroplane.

Yes, the planes are very high tech, but damn!!!!!  Many country's economy is based around the military industrial industry, and will do whatever it can to keep it going, with few if any checks and balances.

At least, in my opinion, customers and the market can make the determination if audio products are worth their time and money. 

I will agree that if the market was greater, you would see much more research into sound quality and real measurements.  As an Engineer, I can tell you that pretty much everything associated with sound reproduction can be measured.  Sorry  to disagree with some out there, but, yes it can be measured.  It has to date, just not been cost effective for Engineers to delve into this and invest the time and money to really do it justice.

However, that does not mean that there aren't some really talented Engineers out there in the audio world.  For example, Mark Levinson, Nelson Pass, John Curl, YBA designer (can't spell his name), Vandersteen, Ralph (Atmosphere), and so many, many more from Europe, Japan, Switzerland, Germany, etc. past and present.  These people really do know Engineering and know their stuff.

it is  one thing to take some one else's designs and build an amp.  it is quite another to start from scratch and do it your self with the math, and measurements to back it up.

A classic example is an Electronics design class where the instructor gives a project to the class.  Design and build a Class A or Class A/B amplifier (including power supply), using all discrete components that have the following specifications below.  build the device in the lab and demonstrate to the instructor that the device operates within specifications.  Show an equations associated with the design, and provide an economic cost breakdown.

Some specifications would include:

1.  Power output:  100 wpc

2.  Minimum Load handling capability: 1 ohm

3.  power bandwith:  DC to light

4.  Power/Frequency stable over the entire bandwidth at rated power output.

5.  Input impedance:  specified number

6.  Output impedance:  specified number

7.  Provide transfer curve equation for the device and be prepared to show simulation on computer model with transfer curve.

8.  Power supply input voltage:  110-120 vac (60 hz) or 220-240 vac (50 hz.


There's lots more, but you get the idea.  And if you think this is easy, remember, they must show all of the math, for the amp and the power supply.

Don't know how we got on this subject but, oh yeah, now I remember....

Anyway, it just ain't true.

enjoy

I agree with Minorl.  I just finished listening to the Gryphon Diablo 300 driving YG Haileys. Yes there was a lot of clean power.  But nothing magical. Im sure A Bryston 4b3 would do a similar job. Secret to great amp is just lots of clean power low distortion. Rest is the speakers the room and source! I have yet to hear Pass though.  I was passing through Reno but couldn't make it to Reno hifi.