Blew my speakers with a guitar - can I fix them.

[mga]

I have a pair of 15 year old B&W DM600s. The woofer on one of them isn't working.

The problem arose when I plugged a digital guitar amp modeller through my hifi amplifier. I know this is a stupid thing to do, but I had the amp really quiet and I was well away from the speakers so didn't expect major problems. Anyway, after playing guitar through this setup for about a week I noticed that the woofer wasn't working on one of the speakers. The tweeter was fine, and the other speaker was fine as well. I tried swapping the speakers around and the problem persisted, so it's definitely the speaker and not the amplifier.

I don't know much about speakers. Is there a way to fix this? DM600s got for well under £100 on eBay, so it would have to be an inexpensive DIY repair.

[richie00boy]

New drive unit time. Ideally you should replace the partnering one on the opposite channel as well. Is it a bass guitar?

[mga]

The drive unit is the woofer ... so I basically need to replace both woofers? Sorry if these questions seems obvious, I'm new to this.

How much is it likely to cost me, and where would I get the parts from? Do I need to contact B&W, or one of their dealers, and what should I ask for? Is the repair worthwhile in your opinion?

I had a Fender Stratocaster plugged into the speakers, via a Line6 Pod modeller and a Marantz hifi amp. What exactly might have happened to cause a speaker to fail?

[Andy G]

have you tested the dcr (direct current resistance) of the dead woofer?

[tomtt]

Originally posted by mga

What exactly might have happened to cause a speaker to fail?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

playing guitar through hi-fi speakers-

use guitar speakers for longer life (many years longer)

[mga]

have you tested the dcr (direct current resistance) of the dead woofer?

I can do, but will have to buy an ohmmeter first. What should I be looking for? Is it likely that I can repair the existing components, or should I resign myself to buying new?

I'm happy to have a go, but don't really know where to start!

[Andy G]

just get a 1.5v-9v battery, hold one end to one speaker terminal, and with a wire, just flick connect to the other terminal.
DON'T hold it on. You will soon know if the driver is dead or not

[sreten]

Hi,

Your choice will probably be one new (expensive) B&W driver
or shoehorning two replacement drivers into the cabinets.

There is an electronics shop in Brighton that sometimes has
B&W drivers in (B&W are based in Worthing near Brighton).
I could check them if your driver is gone.

The other alternative is probably two of these :

http://www.wle-shop.co.uk/modules/sh...odcode=902.423

Though getting them to fit may be a problem, or not.
And of course they are not likely to sound correct but
they will be working in a fashion.

also see :

http://www.skytronic.co.uk/product/p....php?s=902.195

Local supplier :

http://www.skytronic.co.uk/about/storefinder.php

/sreten.

[kevinkr]

No possibility of rebuilding the blown driver? Around here there are a number of options (shops actually) for recone/VC replacement - this is probably dependent in this case on being able to get OEM parts from the manufacturer. I'm not sure how economical this would be compared to a new driver from BW which I would guess is your best bet for performance reasons.

Incidentally if you destroyed one woofer and were driving both channels it is very likely that the other woofer has sustained damage as well - it just hasn't completely failed yet. (I bet the VC wire's insulation is pretty cooked though.)

Depending on what you were doing you may have greatly exceeded the dissipation limits of your woofer voice coils if there was substantial energy in the bass waveform below the effective rolloff frequency of those woofers. You probably would not have even realized it at the time. Hifi speakers generally don't make good MI speakers..

[mga]

Well, this is all giving me a bit of a headache! I wish I'd never plugged in that guitar.

I'm seeing DM600s on eBay for as little as £30 (which is a surprise - I paid £180 for mine 15 years ago) so a repair is not really economically viable - I'd be better replacing them and cannibalising for parts as necessary.

Then there's my intended use. I'm in a really small flat at the moment, and have converted most of my CDs to mp3/AAC, so the sound's never going to be great anyway. The DM600s are actually a bit cumbersome in my main room. I also need a pair of studio monitors and was weighing up whether I could use the DM600s for that purpose instead (they're reasonably flat) and get new (and more ergonomic) for the main room.

In all, I need two good sets of speakers. As you might surmise, I'm on a fairly tight budget for this. I'll spend the cash if I have to. On the other hand, I don't like wasting things, and would definitely keep using my DM600s if I could fix them.

I'll try pulling them apart and seeing if I can unravel something from the self-inflicted mess.