2. amps-preamps
  3. 1103939290

Krell amps and Tube Preamps - enemies?

Wow! I never realized how difficult it would be to add tubes with a KRELL amp. I'm no engineer, and, I don't pretend to be into the "technical" side of the audio world. So I'll try to explain.

It seems that tube Preamps create DC. I've been told that DC will dammage my Krell amp (FPB400cx), and possibly my speakers(Tyler Acoustics Linbrook Sig, System 1 piece). UNLESS, I open the amp up and do something to the "jumpers on the digital board" . This puts some protection into the signal path. The Bad thing is, I'm told, - it also colors or degrades the audible signal coming thru the speakers. So, if I want to use my SS set up, say for SACD or DVD-V/DVD-A, I would have to open the amp up again and reverse the proceedure. This would remove the "blockage" in the signal path. :-( This of course, would have to be re-done when I want to go back to the tube setup. WHAT A PAIN!

Needless to say, this has thrown the proverbial 'wet blanket' on my tube enthusiasm. Is this problem common to ALL SS amps? Or is it just a KRELL thing?

Any thoughts would be helpful.
(This is part of a thread i started on the speaker threads, but i thought i might have more luck here on the "amp' Threads)
Thanks
oldpet
wvick
70 posts
 
Does it damage the amp if this occurs?
bemopti123
303 posts
 
It seems as if BAT preamps are prone to this and if you wonder whether it damages amps, it might in the long run.

Check another thread of the same nature...

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1071085458&read&3&4&
nickt
172 posts
 
I use a BAT preamp and also First Sound preamp with my Krell 450 mono's without any problems.
You should call the manufacture of your preamp and ask them if your preamp leaks dc current. I called BAT and First sound and they told me that their preamp has no dc current leakage so it was safe to use.
oldpet OP
295 posts
 
Wvick - I think dammage DOES occur. I'm not sure what exactly happens, and I don't want to 'experiment' with my Krell.

Newbee - Thanks for the second BTW :-) I might just try a Tubed CDP. I wonder if the (Modded Exemplar, APL) 3910's counts as a tubed cdp?

Nickt - Great Idea. I haven't bought one yet. (good thing I suppose)
But I was considering an ARC "LS" or "SP" 16 (not sure of the difference) or a Cary SLP 2002. I'll contact them to see what they say. Thanks
rwwear
2,868 posts
 
How can you say such a thing Newbee? If one can hear the difference between cables, one should surely be able to hear a capacitor in line with his equipment. After all, they make a difference in speakers. And if someone did make an amplifier that sounded like tubes, who would admit it that it did? I like tubes and use them but they don't always sound better.
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