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

ampage archive

Vintage threads from the first ten years

previous: Carlo M/J, MCM has a Tenma 10A variac (0~... -- 9/3/1999 5:27 PM

Re: update

9/4/1999 12:58 PM
M/J	Re: update Carlo, My voltage in the house is at 110. Seems to be holding at that as I have measured it several times. I did the same mod with the 1k at the screens on another DR last night and it dropped the voltage at the screens and my bias a little...like 1ma but nothing like what I saw in the first amp. The second amp is running at 422@26.5ma This amp also sounds a lot cleaner than the first one (almost like a twin). I tried swapping tubes from one amp to the other to see if that made a difference but nothing changed. There must be something inside that is doing this. Maybe its a variance in the PT? Amp "A" is a 70 model with the proper tranny's and amp"B" is a 73 but the PT appears to have a 78 date code on it. If I get really anal about this and really want to know what the difference is I may check the values of all the resistors in these 2 amps. The 70 sounds better than the 73 to my ears. The 70 has the lower plate voltage. Still can't figure out why I had that big voltage drop. Thanks for the variac info Carlo. I'll shop a little bit before I buy. M/J

9/4/1999 12:58 PM

M/J

Re: update

Carlo,

My voltage in the house is at 110. Seems to be holding at that as I have measured it several times. I did the same mod with the 1k at the screens on another DR last night and it dropped the voltage at the screens and my bias a little...like 1ma but nothing like what I saw in the first amp. The second amp is running at 422@26.5ma This amp also sounds a lot cleaner than the first one (almost like a twin). I tried swapping tubes from one amp to the other to see if that made a difference but nothing changed. There must be something inside that is doing this. Maybe its a variance in the PT? Amp "A" is a 70 model with the proper tranny's and amp"B" is a 73 but the PT appears to have a 78 date code on it. If I get really anal about this and really want to know what the difference is I may check the values of all the resistors in these 2 amps. The 70 sounds better than the 73 to my ears. The 70 has the lower plate voltage. Still can't figure out why I had that big voltage drop. Thanks for the variac info Carlo. I'll shop a little bit before I buy.

M/J

Replies:

Bruce That 422@26.5ma is a weird email ad... -- 9/4/1999 3:18 PM