ampage Tube Amps / Music Electronics	For current discussions, please visit Music Electronics Forum.

ampage archive

Vintage threads from the first ten years

previous: Carl Z John;With regard to... -- 10/13/2000 5:43 PM

Re: Soldano HR50 amp hiss - what can you do?

10/14/2000 3:50 AM
JWK	Re: Soldano HR50 amp hiss - what can you do? Thanks for the info, Carl. I know this is such simple stuff for all the experienced techs here, but I've wondered about this for awhile so it's nice to have someone bring the info down to layman's terms. What I didn't tell you is that I put a 12AU7 in the first position and a 5751 in the second. The third and fourth (PI) were still 12AX7's, but I had tried the 5751 in there with no decrease of hiss at all. I got the preamp stage pretty darn quiet. All the hiss came from the master and presence on full. This was quite a shame because with the NOS tubes the clean sound was very, very nice. So with the high gain eliminated and the preamp stage quiet, what the heck is causing all the hiss with the master? From my limited knowledge this is just before the PI tube. Doesn't that seem a bit strange? John

10/14/2000 3:50 AM

JWK

Re: Soldano HR50 amp hiss - what can you do?

Thanks for the info, Carl. I know this is such simple stuff for all the experienced techs here, but I've wondered about this for awhile so it's nice to have someone bring the info down to layman's terms. What I didn't tell you is that I put a 12AU7 in the first position and a 5751 in the second. The third and fourth (PI) were still 12AX7's, but I had tried the 5751 in there with no decrease of hiss at all. I got the preamp stage pretty darn quiet. All the hiss came from the master and presence on full. This was quite a shame because with the NOS tubes the clean sound was very, very nice. So with the high gain eliminated and the preamp stage quiet, what the heck is causing all the hiss with the master? From my limited knowledge this is just before the PI tube. Doesn't that seem a bit strange?

John