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SET amplifier recommendation

 I have been listening push-pull tube amp for a long time. Finally I'd like to try SET. Seems a lot of people moving from push-pull to SET. My budget is <$3000. Looking at Coincident Dynamo MK III 300B. As there is no dealer for Coincident, i can not try it/hear it. Anyone has this? I'd like to hear your comments. i also looked at Decware, Bottlehead, etc. It seems Dynamo is better. Line Magnetic has some interesting ones. But i am not sure the quality can match Canadian made one. 
    My main speaker is B&W 805. Listening space is less than 400 sq ft. My current push-pull setup is CJ premier 15+CJ premier 17ls2+ Audio Research VT100 MKI. Thank you.
cygnus_859
br3098
994 posts
 
Get a Golden Sound SE-40 PSE amp.
roberjerman2, do you mean the ubiquitous Golden Tube Audio SE-40?  If so, my guess is two of these bridged might work with the OP's B&W 805s but that's a hard row to hoe.  These amps need to be rebuilt and matched in order to extract the best sound and run reliably (ask me how I know this).

The B&W speakers are voiced for SS amplification and are never going to sound their best with tube amplification; possibly with the exception of a pair of Atma-Sphere OTL monoblocks.  My recommendation is to stay with SS or, if the OP really wants to do SET, change the speakers to something more appropriate.

almarg's avatar
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almarg
9,670 posts
 
The B&W speakers are voiced for SS amplification and are never going to sound their best with tube amplification; possibly with the exception of a pair of Atma-Sphere OTL monoblocks. My recommendation is to stay with SS or, if the OP really wants to do SET, change the speakers to something more appropriate.

+1. (Although Ralph/Atmasphere is of course much better positioned than I am to comment on the suitability of his amps for this particular speaker).

And it’s not just a matter of having enough power. Given that the speaker is presumably voiced with solid state amplifiers in mind, which almost always have a near zero output impedance, the interaction of the very wide impedance variations of this particular speaker (see Figure 1 of JA’s measurements) with the relatively high output impedance of nearly all tube amps will result in a tonal balance that was not intended by the speaker’s designers.

Regards,
-- Al




atmasphere's avatar
atmasphere
11,760 posts
 
The B&W speakers are voiced for SS amplification and are never going to sound their best with tube amplification; possibly with the exception of a pair of Atma-Sphere OTL monoblocks.
We’ve got several customers that are very happy with this combination.

Our amps have a lot in common with SETs- quite literally, they are two SETs wired together differentially, with the output bridged. Triode, class A, with a character like SETs of distortion falling to unmeasurable as power is decreased. Unlike SETs they have about 1/10th the distortion, much higher power and wider bandwidth. The cost of replacement for a full set of power tubes for a pair of M-60s is similar to one good 300b.

roberjerman
4,319 posts
 
@cygnus_859: My mistake: the correct name is: Golden Tube SE40. Brain fog strikes! There are some good owner reviews on: audioreview.com
cygnus_859 OP
20 posts
 
Thank you for all comments. I also have some concern about sensitivity of 805. I do ask Israel regarding the sensitivity (both B&W 805 and Polk Audio LSi7). His answer is OK. if the speaker is an issue, i need a pair of high sensitivity ones. Is vintage Klipsch a good option? i heard they are highly colored speaker. But the sensitivity is very high. How different is the sound between 300b and 805 (LM 508AI, etc)?  
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