Help with B&W Speakers

[tubeguy]

I recently inherited a set of B&W DM640 speakers. This is my
second set of these fine speakers and I like them very much.

The speakers are towers and have two 8" low-freq woofers, a
6 1/2" mid and a 1" dome tweeter. These speakers were my
Dad's and he used them with a modified ST-70.

When I got them set up I noticed distortion in the bass from one
of the speakers. I could hear distortion from both of the 8" woofers
on one speaker. I wasn't sure if it was the speakers or the crossover
that was the culprit so I pulled the two 8" units from the other
speaker and tried them in the first. They sounded fine so I believe
I just need to replace the two 8" low-freq speakers in the one speaker.

Does anyone know where I can get exact or suitable replacement
speakers ?

What could have caused this ? Is it possible the crossover is damaged and
the new speakers will be damaged if I just replace them ?

-T

[Petriej]

If the other two drivers sounded ok in the same place as the crummy ones it is more likely that the 2 drivers are damaged than the crossover. Another test would be to place the two suspected bad drivers in the other tower and try them there.

Unfortunately I have no clue where to get them replaced

[AndrewT]

Hi,
try the B&W importer.
They may hold spares or be prepared to import them from the UK for you.
Alternatively, try B&W direct, quoting the serial number.
mailto:uksales@bwgroup.com

[tubeguy]

Yes, I did try that. The speaker distorted in the other tower as well so
it looks like it is the speaker rather than the crossover.

[Foxx510]

Maybe a speaker repairer could rebuild the drivers. It might be easier than getting replacements.

[Henckel]

Try to turn the woofers 180 degrees - so front facia down becomes fornt facia up - this did the trick for me in a pair of old B&W´s

[tubeguy]

I ended up contacting a local shop that deals with B&W. The
8" drivers used in the DM640's were the same drivers used
in the model 802. Of course the only place I could find the exact
speaker was from B&W.

Once I got the B&W Technical Support and Service number
(800) 370-3740. I called and talked with a Tech who quickly
looked up the driver. They had six in stock and could ship the
same day. Unfortunately for me, the cost was $143.90 / speaker
so with shipping it came out to almost $300 for two replacement
drivers.

I'm hoping to get them and try them out by the weekend. I'll
post my results then. I think I'll investigate repair of the existing
drivers if only to have a backup set on hand.

[jacq.]

You could also perform a polarity check using a small 9v battery and see if a bad wiring could have been the culpit . Also see by moving the cones in and out slowly and evenly to see if the are any rubing of the coice coil. It could save you replacing one or the two units.

Jacq.