Bryston 4B3 or Ps Audio M700 monoblock?

d2girls:"both of these amps will sound identical with your loudspeaker assuming they arent wilsons with a sub 1ohm impedance dip. any differences in the midrange and bass will be placebo. amps do not sound different from one another assuming they are driving a well designed speaker with a smooth impedance modulus and phase."

Hello d2girls,

First a few grammar questions: Is your Shift key broken on your device or do you just don’t want to be bothered capitalizing the initial letter on the initial word of each sentence? Is it intended to convey you’re whispering? Perhaps your formal education was cut short after kindergarten for some unfortunate reason?
In any case, it’s very annoying and I thought it’d be constructive feedback for you to realize your odd writing style is communicating more to readers than just your actual intended meaning. The above are only the dubious impressions of yourself that you communicated to me through your nonuse of simple and universally accepted capitalization practices. I’m fairly certain you’re communicating additional negative impressions of yourself to others.
Second a few questions on the content of your post: How limited is your knowledge and experience of home audio to make the presumably honest claim that these very different amps will sound identical to each other when driving the same speakers?
These amps are completely different brands, using completely different technologies and designs. Do you believe all high quality amps regardless of brand, design or being class A, AB, D or tube will sound the same on an identical given pair of speakers?
Based on my personal experience auditioning and comparing used models of the Bryston 4BST and Parasound A21 class AB stereo amps with a new pair of class D D-Sonic M3-600-M mono-block amps in my system all driving my Magnepan 2.7QR speakers, they definitely sounded significantly different from my perspective. I was very impressed with both the Bryston and Parasound amps in my system. I thought they sounded remarkably similar to each other and would certainly recommend either one to anyone desiring a slightly warmer and more forgiving quality added to their overall system sound.
I decided to purchase the D-Sonic monos mainly because I perceived them as having a more neutral presentation which more closely resembles the audio amp ideal of a ’straight wire with gain’. But I also perceived a lower noise floor, better bass response, increased dynamics and very similar detail levels and 3-D soundstage imaging capabilities of the D-Sonics when compared to the Bryston and Parasound amps. The used stereo Bryston or Parasound amp along with a new pair of the D-Sonic mono amps were all priced at about $2,000 so that wasn’t a consideration. The smaller size, lower weight, higher electrical efficiency, cooler operating temperature and the ability to leave them powered on 24/7, however, were also valid considerations in favor of the D-Sonics which may have also tipped the scales in their direction.
I noticed there’s a few individuals on this thread, namely gammonit_2000 and Elizabeth, that have for unspecified reasons dismissed the possibility that the PS Audio M700 mono-blocks will perform very well in your system. I believe this lack of open-mindedness, willful ignorance, blind loyalty to a certain amp brand/type or however it is accurately described is just, at its root, a manifestation of their desire to rationalize an amp purchase they’ve already made. I suggest you value their advise accordingly.
I believe, as you’ve stated you believe, that the ideal method is likely listening to both in your system and deciding for yourself which you prefer. I understand this may not be possible with the Bryston 4B3, but the next best option is probably to visit the nearest Bryston dealer, bring along some familiar music and have them audition the 4B3 paired with a tube preamp and on speakers as similar to yours as possible. Heck, even bring your preamp and interconnects along if it’s not too much trouble. You also already know there’s virtually zero risk with the M700s since you have about a month to try them in your system to make sure you really like them. I’m not certain but I doubt you’ll be able to do the same with a Bryston amp.
The only advise/caution I would add is that the sound qualities of your Rogue tube preamp, or really any preamp’s sonic qualities, will be clearly noticeable when using good quality class D amplification. As will the clarity of any tube, cabling, power cord, recording quality or any other upstream changes in your system. If you’re not absolutely in love with the sonic qualities of your preamp, class D amps are not going to help by masking or flavoring anything.

Best wishes,
Tim

Buy my amp.  It's new, it's Class G.

@benjosef1 


The M700 seems to have a lot of likes... and of course it is returnable. In addition I’d suggest you take a 45 minute drive up to Allentown and visit Digital Amplifier Company as they are getting a lot of great feedback for their class d which doesn’t use purchased class d chips but discrete components in circuits designed by Tommy O’Brien. 

Hello benjosef1,

I thought I should let you know that I’ve never personally auditioned the PS Audio M700 class D amps in my or any system. My suggestion you give them a try in your system was mainly based on professional reviews of their high quality performance, my knowledge and experiences of the high quality performance and sound quality levels attainable through good class D amps in general, the absence of any financial risks to you and the M700’s many other practical advantages over more traditional amps like the Bryston 4B3 and the PS BHK 250 such as size, weight, higher electrical efficiency, cooler operating temperature and affordability.
I believe snapsc’s suggestion of checking out the Digital Amplifier Company’s class D offerings is also very good advice. It emphasizes the points that you have many amp choices at your apparent budget, PS Audio doesn’t have a monopoly on very good class D sound performance and that learning about and listening to as many amps, of all types and technologies preferably in your own system, as possible is an excellent method of determining what you like and don’t like in an amp. You’ll not only be able to make a better informed amp choice for yourself but also be gaining valuable general amp knowledge and experience at the same time.
The last topic I wanted to caution you about is the surprisingly deep-seated ’amp type bias’ that I believe definitely exists, in varying degrees, among many members here on Audiogon and among audio/music enthusiasts in general. I first noticed this here on threads about 6 years ago when I initially began to become interested in class D amplification but it still currently persists. Elizabeth wisely cautioned about this amp type bias in an earlier post on this thread when she warned of class D "fanboys" and taking their advice with a grain of salt.

Good advice that I would suggest we all may want to expand to be wary of any advice giver’s amp type bias since identifying it can often be tricky. For example, Elizabeth wisely cautions of class D biased advice givers even while demonstrating her own bias favoring class AB amps in her first post on this thread when she stated she has zero interest in a PS Audio class D amp. Although her bias requires paying close attention and a modicum of memory, at least she identifies and admits to her own bias which many others completely fail to do when offering advice.
This is probably an opportune time for me to admit to my current bias toward class D amps and finally get to the point of this post. The truth is that virtually everyone with the sufficient meaningful knowledge of, and experience listening to, the various amp types to have developed an amp type bias just means they’ve discovered the amp type that has the qualities that they personally prefer in their own systems. In other words, they’ve developed an opinion based on an open minded and unbiased process of learning about and listening to the various amp types.
However, I suspect that many individuals continue attaining meaningful knowledge and listening experiences as well as keeping an open mind only to the point of selecting an amp to use in their own system. Once they purchase their amp of choice, human nature seems to dictate a shift in thinking and behavior more focused on defending and rationalizing their purchase decision rather than continuing an ongoing learning and experiencing process that explores the various existing and newer amp types in an open minded and fair manner.

My suggestion is to take all audio advice with a grain of salt, mine included, and instead seek to educate yourself via research and frequent auditioning of audio gear, preferably in your own system and room to keep any variables to a minimum. I believe trusting the objectivity of others advice on which amps to utilize in your own system is a poor substitute for learning, listening and deciding for one’s self.

Tim