Cambridge Soundworks Model Six Crossover Problem

[hamdex]

I recently got a pair of Model Six speakers. Everything looked to be in perfect shape except I was told that one of the speakers had a crossover problem. I figured the caps would be shot and needed to be replaced. When I tried to take the speakers apart, I learned that the drivers are actually glued in. When I took the crossover out, everything was already unplugged (explains why it wouldn't play), but I was surprised at what I saw. It seems as though one of the caps had exploded. It this even possible? I tested the crossover (with a fire extinguisher nearby) with some drivers I had laying around and only the bass was responding. I am wondering if anybody could help me get the right caps and maybe other electrical components that are needed. I can solder, I'm just not sure what to get for these speakers.

Pictures:
http://i2.photobucket.com/albums/y14/traxxasman215/DSC00043.jpg
http://i2.photobucket.com/albums/y14/traxxasman215/DSC00044.jpg

 

[RayW]

Yes, capacitors can explode if pushed hard enough. That's one of the reasons techs tend to wear safety glasses.

If the other XO isn't toasted too you should be able to get the values from it. I'd order 2x and redo both of them. The yellow and white round things look to be inductors. Unless there was massive misuse they should be fine. The square white jobs are resistors. You'll have to check values so see if they measure within spec and replace them if not. However it's cheap insurance to replace them as they're usually about $.50 or so. You can get the value on the blue cap (it's on the side away from the pic so I can't tell from there. Get the value on the dead one from the other XO. You can get those from Parts Express. Then just replace one-for-one and you're ready to listen.

You might want to hook up a signal to the speakers in the blown XO speaker to see if they survived. The easiest way to do that and protect the tweeter is use the XO from the other speaker. Should be easy enough since you'll have to pull it to get the values anyway.

Ray

 

[gearhound]

If your going to Parts Express....you might want to consider upgrading from the stock electrolytic capacitors?
The inexpensive Dayton Poly caps would do nicely.

Steve

 

[mhardy6647]

This is the original CSW Six XO, as published in an article on how to upgrade same in audioXpress magazine in 2001.

 

[RayW]

You da man, Mr. H! :thmbsp:

Ray

 

[mhardy6647]

I actually have two intact, unmolested XOs from our CSW Sixes sitting in the basement somewhere. I installed the new XOs described in the October 2001 issue of aX in ours. They've served both of our kids well as college speakers, and now live with our daughter in the fast-lane suburbs of DC.

These are the "new" XOs (well, they were new six-plus years ago):

 

[RayW]

Dayton caps and pegboard. We must have gone to the same school of crossover fabrication. :thmbsp:

Are the "new" ones the same values with upgraded parts or a new circuit? It looks to be the same topology but can't see the values. Did you A/B the new vs. old XO's?

Ray

 

[mhardy6647]

No, it's entirely different. PM me with your e-mail address and I can provide more details if you're interested.

EDIT: While still (I hope!) showing some respect for audioXpress's copyright, here is a little info from the original article, by Jim Forte, on his assessment of the original XO and his rationale for an improved crossover.

 

[RayW]

Hmmm, interesting. I wondered at the shelving circuit (contour). That would bring down everything below ~13kHz thereby making the speaker sound like it had a little more VHF "sizzle". Leaving it out might make the upper mids and lower treble a little more pronounced. Ya gotta do the A/B!

Ray

 

[hamdex]

Well I won't be putting any new crossovers in, but they will be rebuilt. I figured out that I actually wasn't pulling hard enough on the drivers and they were in fact not glued in. Once I took them out, I realized that one of the surrounds was actually so deteriorated that it ripped when I touched it. Seems like I will be refoaming these (first time). Another surprise was that the second crossover also had the capacitor blown. Explains why it seemed so dull compared to the other set of Model Sixes I have. So parts express will have all the parts I need? Where do I get the foam surrounds?

Thanks for the help.

 

[mhardy6647]

yup. You can get very complete resurrounding kits from PE, or if you want to go cheap, MAT Electronics. The former is probably preferred for a first time.

 

[sx70nk]

Almost 12 years later here I come and this thread is not dead YET.
Just got myself the Model 6 speakers and now am interested in checking out that 2001 article about a XO mod. Tried all my voodoo but alas, can't find it on the web. Does anyone here have that info? MHardy??
Any help is much appreciated!

 

[LDvo]

Almost 12 years later here I come and this thread is not dead YET.
Just got myself the Model 6 speakers and now am interested in checking out that 2001 article about a XO mod. Tried all my voodoo but alas, can't find it on the web. Does anyone here have that info? MHardy??
Any help is much appreciated!

Better late than never. In case anyone interested, no voodoo, just plain web search - Jim Forte article attached.