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Wurlitzer 503 amplifier

amateur123

New Member
I recently acquired a Wurlitzer 503 amplifier and some associated electrical boxes as well as a original 15 inch speaker with the cone disintegrated and a 12 inch speaker with the cone also broken. I am wondering if anyone has any experience with these amps or speakers and if the amp is worth repairing for use as a home stereo amp and/or a guitar amp. Are they worth repurposing?
 

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I recently acquired a Wurlitzer 503 amplifier and some associated electrical boxes as well as a original 15 inch speaker with the cone disintegrated and a 12 inch speaker with the cone also broken. I am wondering if anyone has any experience with these amps or speakers and if the amp is worth repairing for use as a home stereo amp and/or a guitar amp. Are they worth repurposing?

I really don't want to bust your spirit here, , , , but....

From what I see in your pics, that'd be an "ambitious" project to say the least, due to the rust I see. Sure, I guess you could remove all the components down to the bare chassis, clean all of the rust off and then use that chassis to build an all new amp on, perhaps using the power transformer if it's still good. I'm not seeing an output transformer on the chassis, perhaps it's attached to the speaker like a lot of old tube radios had. Of course to built it as Stereo you'd need two similar matching output transformers, and this would beg the question of if the power transformer is powerful enough to supply two amps (your left & right sides).

As a fun project to restore it as a mono amp and use it as a (low power) guitar amp, sure, if your a beginner to building tube amps getting the experience is worth your hobby time. But I wouldn't be expecting it to compete with something like a VOX AC30 or something like that, consider it as a "learning experience" only....

Lastly, as to the speaker, yes "re coning" speakers is certainly a thing, and is commonly done. Like any other vintage repair task, it does take a bit of skill to get right, skill that will of course come with the experience of having done it a time or two :thumbsup:
 
Thank you for the advice. Those are good answers to some of the questions I had. I think the output is supposed to run through the speaker coil to clean it up in these amps from what I've read. It appears as though the amp is pretty much all there other than tubes. I know it's just a mono amp which is unfortunate. Sound quality is something I would want if I was going to take the time to rebuild it. Sounds like I should keep looking for a worthwhile project.
 
If you were going to want any glimmer of hope, then I'd suggest checking all the magnetic part windings for ok resistance, and then checking them for suitably high insulation resistance (eg. at 1kVdc). The rest just looks like hard work and aesthetic appeal.
 
It looks like a guitar amp project to me. Or as already suggested, keep the power trany's, output tranys, and chokes. Build a nice single ended amp out of it maybe.
 
I will take some measurements of the windings. It is a big project for sure if I decide to pursue it. I could probably repaint the base metal fairly easily but it will never be original afterwards of course. The fact that it really needs those original speakers to function properly is a bummer.
 
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