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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

wsw siemens ultralinear 815 410 G !!?!

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first of all hello to all,

i just obtained two never used wsw siemens ultrallinear power amps, model 815 410 G from 1963!

They were made for rack mounting but the problem is the output transformer which is modeled for 100V lines!
How can i change that and use the amps with regular speakers??

The other question concerns the fact that there were no tubes in the amp (Ecc84 and El34), so it seems that i have to get new ones. Any suggestions?

cheers
 
Ex-Moderator
Joined 2003
Welcome to the forum.

I doubt that the amplifier used ECC84, ECC83 is far more likely.

The 100V line thing is more of a problem. Have a look at the connections on the output transformers to see if they can be set for conventional loudspeakers. If the transformers can't be connected differently, they will need to be replaced. Fortunately, transformers for EL34 amplifiers are very common. You need to know whether the transformer has ultra-linear taps. If it has five primary wires, with two going to each output valve, it's ultra-linear, but if there are only three, then the valves are probably operating as pentodes.
 
Surely you could simply place a cheaper matching transformer post-output pre-speaker?

Ailbeit it might be better off replacing the output trafos afterall they /are/ PA :\ which are usually of a lower quality.

I'd say your best bet is a Hammond replacement as you might be able to take measurements of the old one and give an exact match: Hammond
 
sorry about the tube number, my typing error.

since i didn't have time to picture the amp properly here's a scan from the papers.
 

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Ex-Moderator
Joined 2003
It's a Williamson driver with ultra-linear EL34 grafted onto the end, and should be good for 20W. For lowest distortion, you're looking for a 6.6ka-a 25W transformer with 43% UL taps. There should be loads of them out there, it's a very common output configuration.
 
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