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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

Showing 10 responses by sutts

sutts OP
700 posts
 
...the statement that newer Mosfets dont' exhibit this response. The Gamut amp I tested was the LATEST model (D200 mkIII).
sutts OP
700 posts
 
It would be interesting to hear from someone else who has heard the Gamut D200 MKIII on reasonably high efficiency speakers...
sutts OP
700 posts
 
Daltonlanny- My Sim W-3 uses Bipolars exclusively- 8/channel
sutts OP
700 posts
 
Sheffb- you're not hearing the 'haze' I experienced because your speakers are 89 db efficiency- not a bad thing, as I will say the Gamut sounded very good with a set of lower efficiency/power hungry Wilson Benesch Discovery speakers at a local dealer's place...
sutts OP
700 posts
 
Wow- a response almost a year later on my original thread- thanks Kalan! OK- you might have something with the Super E/Gamut- interesting observation- what preamp; interconnects; and speaker cables though??
sutts OP
700 posts
 
Kalan- please let us know how the Gamut monos work out for you- curious, how was the Plinius SA-102? Did you have it with the same speakers?? Plinius definitely seems to have their fans as well... btw- I had heard somewhere that the lower-powered (25 watt??) 47 labs amp (Gaincard??) was actually the better soundign one than the 50-watt version...

Cdc & Mural- thanks for expanding the desciption of 'chip'- good info...
sutts OP
700 posts
 
Gentlemen- I will add one note below- an exciting new finding for me... (by the way, no one is going to convince me about that the Mosfet haze doesn't exist- I know what I heard on my reasonably high-efficiency speakers).

I recently auditioned a remarkably uncoloured, yet also extremely communicative set of SS monoblocks. They are the Audiosector 'Patek' SE (the 6Moons guy raved about them I believe). I believed they would be termed a 'gainclone'. The low parts count and superb contruction stunned me, really superb and obviously meticulous build quality- perhaps this translates to the purity of sound I experienced??

I see big potential here- in fact, I compared them to the other 'new technology kid on the block'- digital switching power supply amps, in this case, a set of Bel Canto Ref 1000 monos. The BC's were interesting- but almost TOO quiet between the notes, as if in a vacuum... I found more 'life' in the Pateks...
sutts OP
700 posts
 
Kalan- those are all good points- did not realize the Gamut was 'adjustable' in that way... Hey- a fellow Coincident owner huh? The SEIII's are cool, and in fact more flexible in that I have found a wider variety of amps that can sound good through them. I recently had the Victory's updated to 'II' status at Izzy's place (he lives 15 minutes from me here in Toronto, which is handy!)- increased resolution, yet not in any harsh way, in fact the greater inner detail was immediately apparent.

Jtgofish- sounds like we are on the same wavelength with SS amps- agreed on the chips- they could be the way of the future, however equally likely seems these 'digital switching power supply' amps like the Bel Cantos I tried. In fact, if you can believe this, when I plugged the BC's into the BPT line conditioner, all of a sudden my Accuphase fm tuner went all staticky- sp?? also- my television (also plugged into the same line conditioner) had snowy lines through the picture on certain stations!! Those digital nasties from the amps are definitely not for me- maybe they would work for someone in an all-digital, audio only system with very careful electrical isolation...
sutts OP
700 posts
 
Cdc:

agreed on the bi-polar aspect (and I am not descibing my personality, although my wife may disagree :-). They do have more raw power- case in point- my previous HT system consisted of a few pairs of rather inefficient Totem Mani-2 speakers that sounded great once 'pushed'- the amps I used on them (Sim Audio; Theta Dreadnaught) used bi-polars - they had more 'grunt' if you will, but the speakers needed it.

Nonoise:

thought about the First Watt, however the room is huge and I like to rock out sometimes- I think the FW might lack some balls- I could be wrong- just a feeling from experiencing the Pass Aleph 30 in the same system previously- a nice analog 'warmth', but not the greatest dynamically, and the noise floor too high for me...

However, I find greater 'purity' (I use the term somewhat loosely with solid state,- my Custom 45 2-watt tube amp over in 'system b' would disagree:-) with the best of the 'chip' amps- caveat- given a reasonbly efficient speaker. Perhaps so few parts translates to putting one closer to the music? It's an interesting discussion that would probably make a good thread- overall SS amp toplogies- their pros and cons. Again, speaker & room synergy is the key IMO...

Kalan:

not surprised- Izzy is a good guy, but he is real busy- he tends not to do auditions unless there is a good chance of a sale in it...

Mural:

what chip amps are you speaking of/using? I wonder how their topology would differ from the Audiosector Pateks...
sutts OP
700 posts
 
Kalan- thanks for the updates. How are the Gamut M200 monos on the ambient heat factor scale? are they warm to the touch; do they hear up the room? Incidentally, what is the size of your listening room?
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