Preamp Deal of the Century

ADDENDUM

My post above assumes that you already tried swapping amp, speakers etc. and the problem is in the linestage. If phono, and using a 6106 rectifier, I would take a look at the FET for that particular channel. The 6106 have a voltage drop of 60V, and a maximum dc current output of 125 ma. The 5AR4 on the otherhand is 17 and 250 mA. As you can see, the preamp is being starve not only with the voltage but also of the current when using a 6106. Since transistors are current driven, I would take a look at that first if it was me but using a 5AR4 rectifier.

I seem to remember that Mick was frustrated about units that was shipped back damage from using 6106 tube in the PSU before. IMO, it is possible that what i described above could be the reason.

I could be wrong of course ......

You may want to contact Michael Samra at Audio Asylum. He did some mods on a Supratek, and seems familiar with it.
It may just be a loose connection. I also did these mods to mine and my preamp sounds much better. Better than anything I have owned. Hope that helps.

Here's the mod thread and his name to email him.
http://www.audioasylum.com/cgi/t.mpl?f=tubediy&m=148308

for what it's worth, when i first received the malbecs, one of them had an annoying popping, spitty sound which turned out to be the bias resistor on one of the KT88s. if your tech friend couldn't find any issue with any of the resistors, then i guess you could just email mick or kevin covi for assistance with trouble shooting.

Thanks guys,

I got the Cortese back last night and it seems to be fine now. very quiet. Thanks again for the help. My guy replaced some of the resistors in the line stage and re tensioned some of the tube socket pins.

any happenings in the world of supratek owners? anybody moved on to different preamps? new/exciting mods to their supratek? i hate to see this thread die, but i guess that's just how it will be.