Replacement speaker for GK MB150E combo?

[bwoodman]

I did a search and found a couple threads, but no answer on what speaker would be a good replacement. The stock speaker on mine is trashed from old age - the foam around the edge has disintigrated and after plugging in to test, it's all distorted. This used to be a great little combo amp. Any Eminence 12s that will work in here? Or is my best if I take it to an authorized GK service center? I'd rather have a speaker without the foam surround because that stuff will always break down.

[craig.p]

I personally don't know dog doo about that particular amp, but if you measure the internal cab dimensions, and measure the port dimensions and specify how many of them, then someone here can run some WinISD models for you so you can know beforehand what'll match up best with that box. If the porting is done via a slot rather than via port(s), then provide the internal slot dimensions, including how far back the slot shelf runs. If it's a sealed box, then all you need is the internal cab dimensions. I also highly recommend, long as you're going in there, that you line the inside of that cab with sound absorbing material, if it wasn't done at the factory.

[fdeck]

There is no off-the-shelf driver that will replace the Eminence driver. There are kits for repairing the foam on foam-surround speakers. Parts Express has them. Otherwise, the replacement driver from GK might not be outrageously expensive.

It's an unusually small sealed box, which means that it needs a driver with high compliance, and a fairly massive cone.

[craig.p]

Fdeck, that heavy+loose almost sounds like an acoustic-suspension setup. Is that what they did with that model?

Yeah, I feared it was sealed. Oh, well . . .

[LJ Michaaels]

I picked one up from GK for $109 for a MBE112 1995 model
I looked high and low for an aftermarket speaker, seems the cab
is only made to work with that speaker
There site has them

[fdeck]

Originally Posted by craig.p

Fdeck, that heavy+loose almost sounds like an acoustic-suspension setup. Is that what they did with that model?

Yeah, I feared it was sealed. Oh, well . . .

Effectively, yes.

[TheSuzie]

Don't know what GK is doing these days but I was under the impression that the original models of this series used a driver custom made by Pyle to GK's spec and only available from GK.

Fdeck, did you ever characterize the response of the speaker + cab? I remember that the graph you derived from the response of the preamp was extremely non-linear.

Peace,
S

[fdeck]

Originally Posted by TheSuzie

Don't know what GK is doing these days but I was under the impression that the original models of this series used a driver custom made by Pyle to GK's spec and only available from GK.

Fdeck, did you ever characterize the response of the speaker + cab? I remember that the graph you derived from the response of the preamp was extremely non-linear.

Peace,
S

S, my measurement of the GK response is hidden in my DIY 12" speaker article:

http://personalpages.tds.net/~fdeck/bass/smallbox.pdf

My description of the GK driver's design is based on what it has to be like, in order to deliver the measured response shown. If you're given a particular box size and cone area in a sealed system, the tools at your disposal for driving down the resonant frequency are cone mass and driver compliance. Once the compliance is high enough, then the box itself dominates the overall compliance of the system, and you have to start increasing the cone mass. When push the design this far, it really turns into a simple design problem. Bob Gallien's genius was simply understanding how it works, and having the audacity to do it.

If I wanted to design a speaker from scratch, with similar performance in the same box volume, I'd look at a BP102 with port.

[LJ Michaaels]

The speaker used now is made by eminence only available from GK
I think Bob did a great job with the micro amps, tone to die for!!
I've also paired mine with a MBX112

[bwoodman]

Thanks for all the info - I'm also thinking maybe I can just get it reconed. I'm not far from Orange County Speaker here in So Cal...