richieb Posted November 21, 2005 Share Posted November 21, 2005 Have been toying with the idea of using pure Class A power with my Belles/Corns. Currently using a MOSFET powered integrated with excellent results; crystal clear, zero grain, smooth, detailed and non-fatiguing. My question, do Class A and MFET mimic each other in the way they operate in that both are non-switching? Am I correct that MFET is non-switching? Will Class A give that almost tube-like sound that MFET gives? I may buy the Class A and test one against the other, odd man out. Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted November 21, 2005 Share Posted November 21, 2005 mosfet has nothing to do with class a operation .... do you like the "mosfet mist" ..??? bi-polar devices rule .......... Quote Link to comment Share on other sites More sharing options...
richieb Posted November 21, 2005 Author Share Posted November 21, 2005 mosfet has nothing to do with class a operation .... do you like the "mosfet mist" ..??? bi-polar devices rule .......... "Mist" lifted long ago but I see grandstanding rules over constructive comments. Observing the forum has become much more enjoyable than posting. Quote Link to comment Share on other sites More sharing options...
DrWho Posted November 22, 2005 Share Posted November 22, 2005 what specific amp are you using? and what specific amp are you looking to upgrade to? It's great fun to discuss the differences and inherant limitations to different amplifier topologies, but in the end it is a most pointless discussion as there are always good and bad implementations of each kind...not to mention the complications introduced by the loudspeaker-amplifier interaction. That said, I'm yet to hear a mosfet style amplifier that I enjoy completely...and there is nothing about a strictly class A amp that makes it sound any better than any of the others. Though in a colder listening room a high powered class A amp will work wonders, keeping it warmer for you [] Also, what kind of music do you listen to? Quote Link to comment Share on other sites More sharing options...
3dzapper Posted November 22, 2005 Share Posted November 22, 2005 Richie, Isn't your Redgum Class A biased using MOS FETs as the output devices? That's about as close to tubes using SS devices that I know of. Being Class A biased means that the device is always conducting eliminating turn on transients normally found in bi-polar devices. That iswhat causes the bi-polar AB biased amp to sound a little rough around the edges. Whether there are better executions by other builders I will leave for others. Rick Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted November 22, 2005 Share Posted November 22, 2005 you can run a MosFet amp class a... i don't belive in either... class a may have had appeal years ago, with unsophisticated amplifier designs ... but that was .... years ago .. mosfet ...?? ask DJK what He thinks .....[] Quote Link to comment Share on other sites More sharing options...
3dzapper Posted November 22, 2005 Share Posted November 22, 2005 Duke, Duke, Duke, You are so '70s with those mega amps. The new paradigm is low power clean watts.[][][] I think that is because most of us ruined our hearing in the '70s running a few hundred watts through our Klipschorns. [] Why does loud music always sound better with rope?[6] Rick Quote Link to comment Share on other sites More sharing options...
Colin Posted November 22, 2005 Share Posted November 22, 2005 The paradigm with big ole horns is clean low power. With conventional loudspeakers, the paradigm has always been power, power, power; in an attempt to get the amazing low distortion, clarity, soundstage, dynamics and bass that ultra-efficient horns provide. [] Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted November 22, 2005 Share Posted November 22, 2005 Duke, Duke, Duke, You are so '70s with those mega amps. The new paradigm is low power clean watts.[][][] Rick No, No Rick..... with Klipsch, my amps rarely bump offa 1/2 - 1 watt with JBL, 4 - 5 watts none of the Crowns has Any measurable distortion at milliwatt levels, just ask LeoK but ... Transients ...!!! there's some beef behind the music...... Quote Link to comment Share on other sites More sharing options...
D-MAN Posted November 22, 2005 Share Posted November 22, 2005 I'll say it AGAIN: there is something to be said about a high current amp's large capacity PS even just idling along. It gives a dramatic ability for dynamic changes and the BASS - the BASS even at low watts has a certain solidity and authority often lacking in low(er) power amps! DM Quote Link to comment Share on other sites More sharing options...
sfogg Posted November 22, 2005 Share Posted November 22, 2005 "none of the Crowns has Any measurable distortion at milliwatt levels" Any? That isn't true. I have measured a K2 at those levels. It was clean but certainly can't claim no distortion. I have yet to see an amp that has no distortion. Shawn Quote Link to comment Share on other sites More sharing options...
sfogg Posted November 22, 2005 Share Posted November 22, 2005 DM, I think that difference is mostly that higher powered amps also tend to have lower output impedance. Lower powered amps tend to have higher output impedance. That can effect bass response. Shawn Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted November 22, 2005 Share Posted November 22, 2005 "none of the Crowns has Any measurable distortion at milliwatt levels" Any? That isn't true. I have measured a K2 at those levels. It was clean but certainly can't claim no distortion. I have yet to see an amp that has no distortion. Shawn C'mon Shawn ..... yer bustin' my nuts, right .....??? the D-75 has what. " .003 " at < 1 watt the K-2 is lower ....... can you hear that ..??? ...NOT ..! can you compare to other amps ...????? .......Yes, they are much higher besides ... I don't listen to Specifications ... i find listening to Music much more fulfilling Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted November 22, 2005 Share Posted November 22, 2005 OOOOH ... "measureable" now i see .... i shoulda said ..."audible " ....[] Quote Link to comment Share on other sites More sharing options...
sfogg Posted November 22, 2005 Share Posted November 22, 2005 " yer bustin' my nuts, right .....???" No, I have measured a K2. "can you hear that ..??? ...NOT ..!" Didn't say you can. I said you can see it on measurements. I posted them here. " can you compare to other amps ...????" Yes. "besides ... I don't listen to Specifications ..." Then why post them? "i find listening to Music much more fulfilling" So do I. But I'm not the one that claimed the distortion was not measurable at low levels on a Crown. The attached is a K2 running at .1w into an 8 ohm load. You can see second, third, fifth and seventh order distortion at that level. Shawn Quote Link to comment Share on other sites More sharing options...
sfogg Posted November 22, 2005 Share Posted November 22, 2005 " "measureable" now i see .... i shoulda said ..."audible " ...." That is a different thing all together. Instruments can see things like harmonic distortion long before they become audible. Shawn Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted November 22, 2005 Share Posted November 22, 2005 OOOOH ... "measureable" now i see .... i shoulda said ..."audible " ....[] Apparently You Missed This, Shawn ......[]....[].......[] can't read yer photo .. but of course it's interesting .. frequency .?? how many db down ...?? being SS, you get them odd order harmonics ...too bad they don't behave like a Tube Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted November 22, 2005 Share Posted November 22, 2005 HA ..! our post's Crossed ..[H] interseted in your figures, Shawn, as Crown doesn't spec the K-2 Quote Link to comment Share on other sites More sharing options...
sfogg Posted November 22, 2005 Share Posted November 22, 2005 The test is at 50hz at .1w. About .89v. Second harmonic is at about .0004v. "being SS, you get them odd order harmonics ...too bad they don't behave like a Tube" Tubes have odd order harmonics too. The attached is a tube amp at 1w. Second and third harmonics are showing up. Shawn Quote Link to comment Share on other sites More sharing options...
Speedball Posted November 22, 2005 Share Posted November 22, 2005 I remember Mark D. saying something about J.M. tube preamps work well with MOSFET amps. Quote Link to comment Share on other sites More sharing options...
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