replacing speaker in GKMB200

boombloom · #1 09-02-2008, 04:20 AM

Needed an amp for a gig last week. Took the old (87?) GK out of the bag for the first time in 10 years. Plugged the amp into the PA and it sounded great. Used the unit as a monitor and it was awful. Speaker is shot. Can you please recommend a replacement speaker? There are many options and I don't know how to select just one. Also, has someone done this operation before? Advice appreciated.

Boom

Rvl · #2 09-02-2008, 07:32 AM

This is the response I got from GK

Thanks

Robert

We charge $109.99 plus shipping for the 12" speaker. To place an order, please contact me at 209-234-7300 ext 120.

Kind regards,
Lany
GK Parts & Service

boombloom · #3 09-02-2008, 02:22 PM

I love it here at talkbass. I can't imagine a more helpful response than that. Have you gotten the speaker and done the replacement? I can't even see how to get the grill off...

Mike Arnopol · #4 09-02-2008, 02:26 PM

I've fixed two of them. Get the speaker reconed. No need to replace. The foam gets funky after a while. Cost me less than $30. Problem is that it's a MAJOR pain getting it in and out.

boombloom · #5 09-02-2008, 03:42 PM

Quote:

Originally Posted by Mike Arnopol

I've fixed two of them. Get the speaker reconed. No need to replace. The foam gets funky after a while. Cost me less than $30. Problem is that it's a MAJOR pain getting it in and out.

Reconed? So I have to take out the speaker anyway. What sort of place do I have to find? Who does that? Is there anything new in the way of speakers that I should explore? That's 20 year old technology we're talking about. How do you get the speaker out of that cabinet anyway?

robgrow · #6 09-02-2008, 04:34 PM

The real problem here is removing the speaker and then putting everything back together properly with no buzzes, rattles or air leaks. This is a real pain with the GK 200MB and the early MB150 amps.

If the speaker's foam surround has deteriorated over time (very likely), getting the surround replaced should be cheap enough. A good recone job is not so cheap however. If the original speaker actually does need reconing, a replacement speaker from GK might be a good option.

Replacing the original speaker with another driver is not a very good option however, since there aren't many other drivers that are designed to work in such a tiny box and have the desired response. Trying other drivers would be hit or miss at best and could get very expensive.

alexgeddy · #7 09-02-2008, 04:42 PM

A good reconing job is gonna cost about 65 to 70 dollars....IMO i would go with the replacement!!

My 2 cents worth

Bill

b_carville · #8 09-02-2008, 04:46 PM

Wow! I did it once.
Your talking the old GK self contained black metal 200MB here right? It's a pain but not undoable.
I recall having to take the screws out of the top & sides & slowly bending the metal grill forward to access the speaker screws which are in the back of the speaker not the front.
When you open the top of the amp mind the white lithium electronic grease & when you bend the grill forward be careful of the transformer at the bottom of the cabinet.These were made before the days of no transformer amps.Take your time & you'll be fine.I'm a total klutz with tools & i did it!
Consider another speaker besides the stock one.I was never crazy about the stock one (it was made by pyle). I put an EV Force 12" in and it sounded 100% better.I don't think they make that anymore,but a good Eminence bass 12 would probably work as well & probably sound better & maybe be cheaper price wise.Check US speaker on line.Make sure the speaker goes down to 60 hz at least.
I wish I still had mine! It was a swiss army knife of bass amps.

Mike Arnopol · #9 09-02-2008, 05:41 PM

I've had two of them refoamed, not reconed .Sorry. Usually that's what fails.

Mike Arnopol · #10 09-02-2008, 05:49 PM

I would not reccomend changing speakers. The cheapo speaker it comes with is designed to work in that very small cabinet. Most speakers you'll find are designed for a reflex cab. If you can find the parameters of the original speaker ( qts, qms. etc. ) maybe you can find a better performing speaker. I know lots about speaker design. The air cavity in that box is incredibly small. Very few speakers would work in that box. Even if you put a speaker in that box that had higher power handling, it's a moot point because it's a sealed box. The size of the air cavity will limit the useful excursion of the driver.

boombloom · #11 09-02-2008, 07:04 PM

Quote:

Originally Posted by Mike Arnopol

I've had two of them refoamed, not reconed .Sorry. Usually that's what fails.

OK. I live in the boonies. Where do I look for someone who can refoam this for me?

winston · #12 09-03-2008, 03:46 PM

Find a music store or pro audio shop with a repair department. If they can't do it themselves they should know the closest person who can. Refoaming is a pretty simple process that any speaker fixer should be able to do (I had the speaker in my '88 200MB fixed for $30). BTW the original speaker was made by Pyle.

If you can't do it locally you can ship it to a place like Neal's Speaker Service, who fixed mine.

As others have said dis/assembly is quite a process--be sure to keep track of which screws go where. While you're at it you might want to replace the foam weatherstripping to minimize rattles. You will have to remove the screw that's in the center of the back panel--it's attached to a rubber plug that's glued to the back of the speaker (it'll make sense once the sides are off). Be sure to fasten all the screws tightly when putting it back together.

salcott · #13 09-03-2008, 03:53 PM

I sent mine to GK-they replaced the speaker and did a general checkup at a reasonable price. These amps are a little more than just boxes with speakers and require a tech who knows how to put them back together.

Ric Vice · #14 09-03-2008, 05:59 PM

Quote:

Originally Posted by salcott

I sent mine to GK-they replaced the speaker and did a general checkup at a reasonable price. These amps are a little more than just boxes with speakers and require a tech who knows how to put them back together.

+1
You could certainly have the speaker re-coned if that's what you choose, but sending it to GK may get you the best results, if like me you don't do your own repairs. I replaced the speaker in my B-15 N twice but that's a very easy box to get into, and even then it was tricky, at least for me.
If you have the finances I'd send it to them, unless you have a really reliable tech to do it locally.

Ric

boombloom · #15 09-03-2008, 06:32 PM

Quote:

Originally Posted by salcott

I sent mine to GK-they replaced the speaker and did a general checkup at a reasonable price. These amps are a little more than just boxes with speakers and require a tech who knows how to put them back together.

OK. I'll bite. This is a great little amp and replacement will be alot of money. What's a reasonable price and how long did it take?

tornadobass · #16 09-03-2008, 07:31 PM

GK does flat rate repairs from my experience. I had a flaky MB-150E. They gave it a new (updated!) power supply and a new cabinet to fit the new parts. The cost was $200 plus shipping both ways.