GK 2000RB Question

MLutin · #1 08-02-2010, 09:28 AM

So I recently picked up a GK 2000RB amp for around 400 bucks. Then I found the new GK 4x10 Neos for around 430. All in all a pretty good deal. Anyways thats when the trouble started.

I plugged the amp into the cab using the Left/Low side and I was getting a lot of problems. First off it would play clear for a little bit and then the amp would kick on this nasty fuzz for about 20 seconds then it would turn off. I got sick of hearing it so I started using the Right/High side. Now it doens't kick the fuzz on, but the volume will be fine for about 5 mins then every minute or so the volume would dip to almost mute.

Now I have the 8 ohm cab in full range mode, and the Amp in bridge/full range mode. So I'm wondering what the problem could be. I was thinking it could be the wiring in my house since its not even a grounded outlet. But I just want to make sure I'm not damaging my equipment.

I looked on the GK website and found the manual, it says I may need a special speakon cable to bridge the amp to 1 speaker. Any idea where I can find such a cable? Thanks for the help.

62bass · #2 08-02-2010, 02:09 PM

I used a 2000RB for a few years and had no problems, which was usual for me with GK. So I don't know what could be going on with yours. I'd suggest contacting GK by phone. They're really good with customer service. One of their guys posts here and may see this post as well and answer it.

I think the special cable is only required if you plan on bi-amping your cabinets and it is wired to work with GK cabinets only.

jelwood · #3 08-02-2010, 02:11 PM

You're running the amp incorrectly. The 2000rb bridge mode switch must be set to OFF if you are going to run through the right side! NEVER set that switch to ON if you are:

1) using a regular 1/4" speaker cable to hook up to a cabinet, even if it's the left side
2) Running through the right side
3) running in bi-amp mode

You MAY set that switch to ON if you are:

1) running through the LEFT side ONLY with a "bridge speakon cable."

Clean the effects return jack with deoxIT. Can be bought on partsexpress.com This will fix your volume issues.

To rewire a speakon to work with bridge mode, first pick a side of the cable you want to plug in to the head and MARK IT WITH A SHARPIE OR SOME TAPE so you don't confuse it with the side that goes in to the cabinet. You will need a 4 pin speakon cable. For the side that you have chosen to go in to the head, move the wire that connects to the 1- pin to the 2+ pin. Disconnect completely the wires that originally connected to the 2+ and 2- pins as you see fit and make sure they won't touch each other (this goes for the side that goes to the head and the side for the cab). Do not mess with the 1+ and 1- pins on the head that goes into the cab. You will be good to go. DO NOT USE THIS CABLE UNLESS YOU ARE RUNNING IN BRIDGE MODE, ON THE LEFT SIDE.

I'm done now.

The 2000rb is a maginificent amp, it just wasn't very user friendly and rather complicated for a GK. But once you've got it figured out, it's simply the best.

Edit: the 2000rb uses traditional bi-amping and not the modern horn management system you will find with amps like the 700rb-II. When using a speakon to connect to a cab, either in bridge mode or not, set the cab to full range. If you want to bypass the horn completely you can do so by using a 2 pin speakon or if you're in bridge mode, your bridge cable, and setting the cab to bi-amp. Oh, and playing through a grounded outlet is always a plus...

MLutin · #4 08-02-2010, 02:16 PM

Yeah, it seems like a really good amp with a lot of functionality, Hopefully I didn't damage it at all. So even if the left power output is fuzzy, clean the effect return jack? I'll give it a shot. Thanks for the help!

jelwood · #5 08-02-2010, 02:20 PM

Don't use rubbing alcohol or anything for the cleaning...