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Del
05-06-2003, 01:17 PM
Can a 70's silverface twin be converted to a black face,any links to companys that provide parts:D

Josh
05-06-2003, 11:03 PM
Del,
Generally speaking, the earlier the silverface model is, the easier it will be to blackface. The most difficult ones to BF are the late 70's 135w ultra-linear models.
Most of the differences are in the phase inverter, if I recall correctly(been a long time since I have done it). Most of the parts can be found at basic electronic suppliers like Mouser electronics.
You will have to find a schematic for your model, and one for a mid-60s twin, ...just compare the differences.
Josh

Jon Silberman
05-15-2003, 07:45 PM
It's my understanding the ultra-linear models cannot be converted to blackface specs.

Josh
05-15-2003, 07:54 PM
You can disconnect the ultra-linear taps or replace the OT.
I think the PT ran at higher than vintage voltage though.
Josh

Jon Silberman
05-16-2003, 04:09 AM
Theoretically and with enough effort, I suppose anything is possible.

Do yourself a favor. If you want a cheap SF TR to convert to BF specs, make it a '68-'76 100 watt model.

Stay far away from the '77-'82 135 watt ultra-linear model.

I'm no tech myself, but I read alot. Never have I ever heard of anyone who bought one of those with the goal of BF'ing it succeeding to his satisfaction.

Del
05-16-2003, 12:50 PM
It is an early 70's point to point all oragional and CHEAP:D

Josh
05-16-2003, 02:50 PM
I would go for it...easily blackfaced, altough the early 70s twin sounds good regardless. Get a cap job, and maybe a set of tubes with a proper bias. You could sell it and get your money back at any time, these amps will only go up in value

Josh

Jon Silberman
05-16-2003, 05:35 PM
Follow Josh's advice IMMEDIATELY! :D