Speaker/horn problem?

[lowendblues]

I have a GK MB500 head running into a GK 112-II NEO cab. When I fret a note and let it sustain,, just as the note decay's it creates a distorted, fuzzy "broken up tone". Is it the horn or speaker? I've ruled the amp out.

[KJung]

It it sounds like cellophane wrap crinkling, and you can hear it at low volumes similarly to the decay of note, that is typically a damaged speaker.

Turn off your tweeter and listen closely to the woofer at low volumes. If it is still there, that's probably what it is. If not, could be the crossover, or even a preamp tube.

[craig.p]

How 'bout making up an acoustical divider of some sort so you can isolate the distortion to either the 12 or the tweeter? Use a cardboard box with both ends knocked out, for example.

EDIT: Whoops, KJ beat me to it.

[lowendblues]

Ok, I'll try that. I've ruled out the MB500, I get the same effect with a different amp.

The cab has never been run hard, just noodled with around the house. However, I am using a GK supplied cable that enables you to use the biamp feature. ( I used it with my old 700RBII.).

Since the MB500 is not a biamp head, could that have damaged something?

I realize you have to be careful with GK's speakon cables.

[KJung]

Originally Posted by lowendblues

Ok, I'll try that. I've ruled out the MB500, I get the same effect with a different amp.

The cab has never been run hard, just noodled with around the house. However, I am using a GK supplied cable that enables you to use the biamp feature. ( I used it with my old 700RBII.).

Since the MB500 is not a biamp head, could that have damaged something?

I realize you have to be careful with GK's speakon cables.

I don't think using that 4 pin speakon, or whatever that is, will 'damage' anything. However, you might try another speaker cable just to make sure something isn't funky. I think the GK head uses the combo speakon jack outs, so if you have a 1/4" speaker cable laying around, try it to make sure.