Aragon 4004 mk2 vs Adcom 555 mk2


Anyone done any real comparisons with these 2 amplifiers? Opinions on both? Bass,mids,highs,soundstaging? Thanks
kool39
If the feedback signal were perfect with regard to gain and phase it could only improve the overall performance of the amp. High amounts of feedback become a problem when the feedback is less than perfect, either because of circuit design or real-world component tolerances. "Too much of a good thing".
Yep, anything in excess is bad, feedback included. Yet, I don't understand the hang up that audiophiles have with feedback. When I say feedback, I mean GLOBAL feedback. It has a zillion advantages that any engineer can name off for you because in the rest of the electronic world, feedback is absolutely critical in just about every circuit I can think of. In audio, I don't think feedback causes any detriment to the sound per se. I have looked this up several times and the post Gmood pasted above has too many inconsistencies to be reliable IMO. Local feedback is present in 99% of amps. I talked to Nelson Pass and what he calls "zero feedback" means he has local feedback but no global. This is fine however no one ever seems to complain about local feedback sounding poor. Kind of funny that guys who buy zero feedback amps for the name are actually listening to high local feedback designs and proclaiming its benefits. An amp with no feedback at all, will crash and burn with most speakers. I guarantee it. I have seen it in the lab many many times. So, before complaining about feedback sounding bad, consider what I have said. There is probably an exception out there somewhere (meaning no NFB at all) but we probably wouldn't buy it due to audible oscillatory reactions with the speaker's reactance. Arthur
You probably have less problems with feedback phasing around one stage (local) than across the entire circuit. So in the real world, local feedback may be less problematical than global feedback, even if the net total dB is the same. In an ideal world, both would be perfect.

It is unfortunate that we use the word "Negative" to indicate polarity of the feedback. That word has negative connotations.
Im not an engineer by any means but I kinda thought that ALL products have to have feedback of some kind. But Ive been in arguments in the past where people are telling me their products sound "superior" due to 0 feedback, and that they can "hear" the difference between amps with feedback and amps with no feedback which I kinda felt was a bit flakey. Ive always thought that what matters in the end is how good the product actually sounds regardless of design,pricetag or "brand name".
I agree with you on design,price tag and name.. Ritteri.But that being said with the right two amplifiers you will be able to hear a difference.Whether it's for good or bad it's not that hard to hear.I suppose there's no absolutes to anything especially in this hobby.Sounds like those Pallidiums are some great amps.Aball you should try to audition some Monarchy 100 SE monoblocks on your Paradigms I guarantee the differences will not be subtle.Also Arthur do you know if the Macs use any Global feedback or just local feedback? Just curious.