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SS amp mosfet 'haze' - ever experienced this?

Tried a new amp in my system on the weekend: the well-reviewed Gamut D200 mkIII (partly based on HP's great review), a single-mosfet SS design. At the dealers' place, it sounded great (speakers were Wilson Benesch Discovery, an isobarak, lower-efficiency design). I can't use a tube amp right now (unfortunately!) due to pending child and the system is on a LOT (2-ch/HT mix), so am looking for the most full-bodied SS amp I can find (prefer fully balanced design to match my modded SF Line 3 pre).

Well, to my surprise, the amp did NOT work out as well at my place. My speakers are 97db Coincident Total Victory. Yes, it was full-bodied, but I was definitely aware of this haze, or veiling around each note. I have a friend who designs amplifiers, and he said that this is inherent of mosfet designs. I called Israel (Coincident) and he was not surprised that I only heard this once I got back to my place, due to the high resolution abilities of my speaker vs the speakers at the dealer's. I guess I will be sticking with my Sim Audio W-3, as it is much 'cleaner' on my system (given that I must stay with SS). Too bad, 'cause my Sim W-3 definitely has the edge in clarity, but the Gamut was a touch more full-bodied.

Has anyone else experienced this 'haze' with a mosfet-based design? I admit, those with higher-efficiency speakers like mine (97db/14ohm) probably are NOT using higher-powered mosfet designs anyways, but I would like to know how others feel about mosfet designs and this issue I had.
sutts
tvad
9,467 posts
 
08-22-06: Muralman1
Yeah, but I get to choose the color of the day. You know that about tubes....
There's no difference between our systems there either, as I can roll half a dozen or more tubes in both my preamp and amplifier, and by so doing I can change the sound of the system in a number of ways...from uber clarity and resolution, to warm and fuzzy and less resolving.

I'm not trying to one-up you here at all, but you cannot claim "Yeah, but..." as a benefit or difference between your chosen method and mine. It still comes down to shifting the coloration by changing tubes.

Which seems to highlight the superiority of tubed gear, even if a system utilizes only one tubed component. Eureka!
muralman1
1,527 posts
 
The question still is, "Has anyone else experienced this 'haze' with a mosfet-based design?"

The answer is.......... drum roll........... Yes!
tvad
9,467 posts
 
08-22-06: Muralman1
The question still is, "Has anyone else experienced this 'haze' with a mosfet-based design?"

The answer is.......... drum roll........... Yes!
I cannot presume to be able to narrow the cause of the sound of my Moscode 401HR to its MOSFETs, to it's input or driver tubes, or to the utilization of these parts and the rest of the parts in the overall design of the amp, and I'm dubious of anyone's ability to hear and separate any sonic attribute of MOSFETs from the rest of an amplifier's parts, unless that person is an amplifier designer with years and years of experience.

However, I also will not rule out the possibility that all the hobbyists contributing to this thread who claim to be able to hear the difference between MOSFETs and bi-polar outputs, independent of the amplifier designs in which they are used, are audio savants.
undertow
1,032 posts
 
Tvad, I thought you used Odyssey mono's? Those are bipolar, what is your impression of those vs. the mosfet or any of these others? Just curious for my own knowledge, thanks.
tvad
9,467 posts
 

08-22-06: Undertow
Tvad, I thought you used Odyssey mono's? Those are bipolar, what is your impression of those vs. the mosfet or any of these others? Just curious for my own knowledge, thanks.
I owned Odyssey Monos for a short time. I cannot give you a comparison of the two amps based solely on MOSFET vs. bi-polar for reasons expressed in my posts above.

The Moscode is more to my liking than the Odyssey amps in every regard.
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