Half Working SWR Tower

[Awesomenaut]

My first cab, and my first post here. There had been this SWR Workingman's Tower sitting at a local pawn shop for ages, and I've always dreamed of having an 8x10.

I went in and finally convinced them to cut me a deal on this. Giddy as hell I ran home, grabbed my amp, ran to the bank and withdrew the $450 they wanted for it.

I went back to test it, plugged everything in, and WHAM the sucker was loud. I turned a few knobs on my amp to make sure the response throughout the different frequencies was OK with me, and took it home.

Excited as hell I plugged the thing up and started being obnoxiously loud, I had a friend over and he checked it out...we were both impressed.

However, upon closer review somebody has definitely messed with the speakers, and upon even closer review I realized that only the bottom four speakers were working. So, really, I have a 4x10 in an 8x10's body.

I'm not very well versed in the ways of amplification and whatnot, but I'm wondering what this means. My theory is maybe something to do with the crossover, if this thing even has a crossover and if I'm understanding how a crossover works.

Anyway, I'm wondering if anybody has any theories. I like this cab, even at half it's capacity, and I think that I'm pretty much stuck with it now. How much will a repair cost, and will I be getting boned in the process of having it repaired? Is it something simple that maybe I and somebody with a bit of knowledge in electronics could fix ourselves?

 

[T-Bird]

Hi.

Welcome to the TalkBass.

I have no personal experience with that particular cabinet, but since it's a single chamber box, using it loudly with only half of the speakers working isn't advisable. It probably won't break anything but the non functioning 4 acting as passive radiators in a bass reflex box (?) won't improve the sound much.

One possibility is that it's wired as a stereo cab, but again, the single chamber design don't make that cab a feasible candidate for such a job.

Since it's a 4 Ohm enclosure (originally) there's a couple of ways to acchieve that. If it's 8 Ohm speakers it's most likely 4 pairs of speakers in series (16+16+16+16), grouped again in parallel (8+8) and those two in parallel. There's many more to coose from, especially if the drivers aren't 8Ohm, but that's the way I'd wire it. And one open connection in either of the last 8+8 groups would result just the symptoms Your'e describing.

Your best bet IMHO is to contact the store and tell them to repair it or cut the price in half.

Regards.
Sam

 

[Awesomenaut]

Yeah, it was originally a 4ohm cabinet, that's for sure.

The Sunn Concert Bass I'm using is also pushing 4ohms, which makes me wonder how this thing is working right now.

I think the best option for me right now is to sit on it for a while and resist (no matter how hard it may be) the temptation to play it, and once the funds are available take it to a tech.

$450 for an 8x10 is a steal in my opinion, and the buyer's remorse I have right now, even with it being broken, is very little. I just hope I don't end up spending enough on repairs to make my initial investment not worth it.

Any other theories or opinions?

 

[ducatiman]

pull speakers, inspect for faulty wiring. while there, verify speakers all match. you may also want to determine if speakers are, in fact , original and working (individually) while you're there.

an investment in your time and labor will cost nothing and you may get lucky and easily find the problem.

hint...being that all top 4 are not working, i'd guess theres a wiring fault somewhere.


good luck.

 

[mrkreuzschlitz]

If all the wiring looks fine, pull the speakers and check with a 9v.

 

[anderbass]

Don't know about yours, but on some cabs its fairly easy to remove the rear jack-plate (check for a loose wire here) and/or sometimes the handle assemblies to view inside and make sure all speakers are still plugged in. See if all speakers apear to be the exact same type looking from the back side too.