|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
64.122.72.31
In Reply to: RE: DAC offset on ma-1 posted by ChasLieb on November 18, 2014 at 19:52:28
On a 12-tube model the driver tube is the last one of the row in the rear, away from the input connectors.
If one section is weak, this can cause a DC Offset that can't be corrected.
Another symptom of a bad driver tube is the DC Offset mysteriously changing without any other reaction from the amp (such as an obvious output tube arc).
Follow Ups:
Hi Ralph
Are you talking about the last 6sn7 or the last pair of 6as7 tubes?
Charles
If you have a 12-tube MA-1 and it has 6SN7s, then it will be the last one in the row. The earlier driver used a 6CG7.
Mine are MA-1 deluxe that were brought up to 3.1 so they have 6sn7 drivers. I did a recent retubing and thought I tested each tube but replacing the last 6sn7 in the line brought the offset down to zero. Thanks Ralph!
Charles
to have the resources we have here? We are lucky.
ET
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: