Vintage Combo Amp Redux

[Jero]

I have a late 60's Sears/Silvertone 40xl amp that has been needing some light work.

It was sent to me inside a box that was 3x too big, with literally ONE piece of bubble wrap. When it got to me there was a hole through the side of the box where someone put their foot through by the looks, and the amps condition was certainly jeopardized. The frame around the chassis had been smashed to the side.

Currently, I am building a box for the chassis to make a standalone head unit. I'll be removing the broken excess wood from the 12in speaker/combo portion, in order to make a standalone 1x12 as well.

I'll post pictures as this project chugs along

[sidandnancy]

That thing looks vile! What a heartbreak that it got broke  .

I'd go with red dot = +, and if it turns out to be out of phase with the rest of your stuff, just swith the wires on the jack.

[Jero]

Hey thanks for the reply! I'll give it a try and see how she goes.

The amp certainly has character, perhaps even "awesomely ugly," very fitting for the brand. Same for the tone, thing looks like a beat up washing machine or something, but sounds a beaut'!

[crochambeau]

I'd go with red dot = +, and if it turns out to be out of phase with the rest of your stuff, just swith the wires on the jack.

Agreed. The only vintage speakers I know of that are notorious for red marking the negative lug are JBLs, no harm can occur through reversed wires.. follow your ears.

[sidandnancy]

I just remembered an old trick. Attach some wires to the terminal and touch them to a 9V battery. If the cone jumps forward, you have the correct polarity. If it sucks in, you need to flip.

[crochambeau]

If the cone jumps forward, you have the correct polarity.

If it pushes out, look at the battery and the polarity printed on the battery reflects the polarity of the speaker. (just a clarification)

Avoid this test with mid cones and especially tweeters, they can be adjusted by sound alone (depending on crossover they may be intentionally reversed anyway to maintain phase relationship at the crossover point).

[Jero]

I just remembered an old trick...

I forgot all about that! Though I already hooked it up as red dot = +, and it worked fine. FINALLY got to run it into my sovtek 4x12....

I managed to get a good bit of this done today. The frame for the chassis is cut out, the the cab is now isolated, and a few other things got done. I still have to do a few minor, yet important, things before it's "finished."