Replacing the speaker in an old-is GK MB150S

[Jeremy Kahn]

Once I've heard back from GK I will disassemble the amp and post some photos. The speaker is exactly as in the photos but it has a sort of rubber grommet attached. This has perished. My question is not whether the grommet exists, but where can I get one, what's the specification for it.

 

[crazyBassClown]

GK would be where to get it from, unless you can work out the specification yourself.

 

[Grooveman]

I would shoot GK an email.

Hello I have just finished replacing the speaker in my 200 MB.
Does it resemble the rubber piece pressing against the back of the speaker and scoot into the back of the cabinet ?
This piece of rubber was just wedged in between the speaker coil and the rear of the cabinet with one screw coming in from the back to hold in place so actually the speaker is not attached to it .
You could cut a piece of rubber to fit the gap as I think it is there to keep the cabinet from vibrating .
Best wishes

 

[bucephylus]

Some interesting info in this thread. Thanks all.

I repurchased an older MB150E112 seven or eight months ago; and it totally had the rattles. My solution was to stuff one of those gardening kneeling pads in the back of the cabinet; and that seemed to clean everything up. Still, it's interesting to see that GK still supports the drivers. I wonder if they still sell that rubber post?

They really are fantastic little amps. I always regretted selling mine back in the day.

 

[PeckBass]

Hi all and happy new year! I'm curious if anyone tried a lighter neodymium speaker in a GK MB??
Thanks, np

 

[agedhorse]

Hi all and happy new year! I'm curious if anyone tried a lighter neodymium speaker in a GK MB??
Thanks, np

IIRC, that's a very small sealed cabinet. The original driver was optimized for that application. It would take some work (and math) to determine what new driver might work ok.

My suggestion is that it it's not broken, leave it alone.

 

[fdeck]

I have a MB150E combo, and analyzed the heck out of the speaker long ago, just because I was curious. I think a unique thing about that driver, is that it has a highly compliant surround and also a massive cone. My search never turned up a comparable driver.

The engineering tradeoffs that Bob Gallien made, to get gig-worthy sound out of a one cubic foot package, were quite ingenious.

Also, a neo driver will make it lighter, but not profoundly so. There's still the big iron power transformer, and heat sink, in there.

 

[agedhorse]

I have a MB150E combo, and analyzed the heck out of the speaker long ago, just because I was curious. I think a unique thing about that driver, is that it has a highly compliant surround and also a massive cone. My search never turned up a comparable driver.

The engineering tradeoffs that Bob Gallien made, to get gig-worthy sound out of a one cubic foot package, were quite ingenious.

Also, a neo driver will make it lighter, but not profoundly so. There's still the big iron power transformer, and heat sink, in there.

Absolutely correct, there were some unique tradeoffs made and the driver is very uncommon (hence the reason it's a custom OEM part).

 

[PeckBass]

Thanks for the great info everyone! Ima leave that thing alone!!