Why do audiophiles shun feedback in amplifiers?

I have two push-pull class AB amplifiers. One is 40 watt/ch with EL34 tubes and the other is 100 watt/60 watt(UL/Triode).The bigger amp is one of the best PP amps I`ve heard it uses 6550/KT 88/KT90 etc. This was my main amp,top choice for driving my Coincident speakers. Three years ago I purchased my 300b SET 8 watt amplifier.From day one fresh out of the shippng carton this SET put the others into storage. It was simply better across the board.

The 100 watt amp has more bass weight and impact(the gap is`nt large however).In terms of tone,harmonics,noise floor,presence,3 dimensionally,nuance and dynamic ebb and flow the SET is superior.When playing high energy big band jazz ,the ability to clearly seperate and hear the individual instruments is extraordinary.The scale,energy and dynamics completely fill my room, it really as if the walls vanish(I`m right there at the venue,spooky real). In the sense of realism,believability and natural sound it`s the best I`ve heard so far.Some SET amps are better than others.The better quality DHT SETs are the most live-like,realistic and trueful amplifiers I`ve ever experienced. This was a profound moment for me as it put me into a different sonic realm,there`s no going back.I`ve own SS (Symphonic Line amplifier) it was`nt close to this.My 100 watt PP was better than it in terms of live flesh and blood presence.The 300B SET is a new standard however.

Just an example of how people have different experiences and impressions. The good news is there`s an amplifier topology out there for everone. SET,PP,OTL,SS,class D, take your pick.What I have discovered with SET I know others have experienced with other types of amplifiers also.
Regards,

"I have found amps with less or no feedback sound loose and diffuse with less dynamics... I know you should design am amp with excellent open loop gain before applying feedback. I can see the use of no negative feedback for low level amplification (eg, preamp and gain stage of CDP or DAC). So why this myth perpetuated by audiophiles and even many manufacturers?"

I don't see why you would say that 0 feedback components better SQ is a myth. If you can, try to audition some Ayre products. That will probably change your mind. (There's other great sounding 0 feedback electronics other than Ayre. I recommend Ayre because I feel that they are the best example.

So here's a question.

Can an amplifier with no or minimal negative feedback in play make a CD recording that might be irritating otherwise normally not irritating? Not all recordings are created equal. SOme are more irritating than others for various reasons. I'd say only a very small % of my thousands of CDS, maybe a dozen or less, mainly in the hard rock/heavy metal or a few electronic dance genre MP3 tracks, sound as Atmasphere describes a negative feedback amplifier in practice. I listen to all my CD tracks queued up randomly, so I do not know what I will hear next, yet there is that occasional REM or MEtallica CD that will play and be hard to listen to, but most of the rest seem to sound more like what Atmasphere describes for non NF amps. SO I am not hearing the problem at least, FWIW.

THis is the case even with my Dynaudio Contour monitors, which tend to have a significantly hotter sound running off my gear in their room than say my more laid back OHM Walshes in others.

Can an amplifier with no or minimal negative feedback in play make a CD recording that might be irritating otherwise normally not irritating?

Mapman, you basically asking if it is possible to make amplifier bad other way than NFB. I'm sure it can be done 100 ways from bad power supply to wrong bias current.

NFB is producing TIM only when overused. We're talking global NFB since local ones are almost always there. Transistor amplifier output stage represent voltage source. For that it needs to be regulated = NFB.

Mapman,
In my experience the answer to your question is no. The one quality I`ve come to admire over time with my SET is honesty. What ever is the inherent sound character of the CD that`s what I`ll hear,flaws and all. Some SET amps could perhaps'pretty up' the sound but my does`nt do that. I have some recordings that are thin,brighter and in some cases edgy and that`s how they will sound.But those that are recorded well,oh my goodness.

My SET has less editorializing than all of my previous amplifiers. I reconized this aspect early on, It just seems to preserve the signal with minimal influence.The effect is heard as pure and unfiltered.
Regards,