Gallien kruger 2001rb.....oppseedaisy!

[nevetslab]

I kinda feel ashamed the entire task taking me 41 hours to complete. Expensive education adventure and hand-slapping for mis-connecting a connector. I know the amp a whole lot more though. I see why GK added the inconspicuous 15A pico fuses on the +/- 38V supplies on each channel. When mis-connected and no fuses, it will eventually take out the mains fuse, but not before doing damage to the foil pattern. I'd only mis-connected on once before, and it had to have been the Right Channel, and had the pico fuses.

[nevetslab]

While ordering parts at Mouser to re-stock my electrolytic cap inventory, I looked to see if I could find replacement handles for this 2001RB amp. 3.75" mtg centers. Turns out that mounting center is one that few to none offer any more....or at least nobody is inventorying them. RAF, Amatom, others don't offer any of their handles on those centers. So, I called GK, since it IS their amplifier anyhow, and have them sending new handles, along with the rear stiffener panels that mount behind the chassis rack flanges, folded out from the side panels. And the mtg screws, of course. I also got them to send me the latest 2001RB documentation to add to my database. I did give them the S/N of the amp, though I'll laugh if what they send me is on 4" mtg centers instead of 3.75" ctr's.

[nevetslab]

Amp making loud noises when touching front panel with guitar cord plug tip

After GK completed the parts order for the new panel handles & hardware, I got those installed. They sent 1/8" stiffener panels to fit on the back side of the rack panel flaps, but weren't counter-sunk for the flat head screws they sent. So, I c'sk'd them and went to install the screws & handles. The stiffener panels wouldn't fit...too wide, then of course, the holes didn't align. Went without the stiffeners, only to find out now the # 10-32 screws they sent bottom out into the handles. Sigh.......replaced the screws with shorter ones, that task now done. So, this afternoon, I sent it back to the Guitar Dept.

It came back half an hour later, with the complaint that the input jack doesn't work. Nonsense. Everything was working solid as a rock...and was just waiting for the handles. I found they had switched it back into Bridge Mono, and nothing was coming out of the 1/4" phone jacks. Switched it back, got output on both channels....but....every time I plugged into the input jack, I was getting loud noises, same when unplugging. Same happened when just touching the front panel with the tip of the phone plug! What the?????

At that point, having already put more than 41 hours into this POS, I was looking for a brick wall to hurl it at.

Something isn't isn't making sense here.

AC mains current draw is still the same as it was when I got everything working correctly. I didn't notice there being one of those special phone jacks on the front panel INPUT jack, where nearly hidden, a very tiny metal protrusion that's part of the Ground PCB terminals. But still.......just changing from tightened # 10 screws and keps nuts holding the panel to the chassis to installing the handles to accomplish the same task....that surely can't cause this.

[nevetslab]

4 months later, NO OUTPUT!

After the lengthy battle I had with this 2001RB, I thought I'd seen the last of it for a few years. It came back to the shop 12/19/18 with No OUTPUT.
It took a moment to psych my self up to face it, then pulled the top cover to see what adventure was held inside. It was the Left Ch that had failed before, and what I found was the 7-pin AC Secondary connector unplugged from the PCB. Well, if you want to disable a 2001RB, that's the connector you want to unplug, as you loose the low voltage bipolar supplies to run the preamp for both channels.

Why was it disconnected?

I checked the pico fuses on the Left Ch, which were ok. Checked all 3 bridge rectifiers, and they were ok, along with the 6 3A rectifier diodes in the same area, all ok. Checked the same on the Right Ch, all ok. Apart from the disconnected plug, nothing looked wrong, so I re-connected that, plugged in my DMM into the Left Ch output to monitor DC voltage, and clipped on the other DMM to monitor the V++/V-- while bringing it up on the variac, watching the ammeter of the power analyzer.

All came up just fine. Powered down, moved the DMM connections to the Right Ch, powered back up, just switching it on this time, not having seen any surprises. All ok on the Right Ch. Connected the test speaker to the Left Ch, injected pink noise into the input, and found all the functions working fine, as well as out of the Right Ch.

After I powered it down, and loosened the power xfmr to rotate it a bit to get more slack on the secondary wires bundle, the Left Ch connector popped off the PCB header! I'll be buggered! That's why it didn't work. The locking ramp of the header had weakened enough to stop holding it, though the connector sockets felt tight. I put an adhesive-backed tie wrap hold down block atop the closest power supply cap, dressed the harness & its' connector so it would have holding tension and strapped it into place with a tie wrap.

Breathed in a sigh of relief.

[Jazz P Bass]

"I'll be buggered!".

Been there.

[glebert]

I think that amp just missed you.

[shortcircuit]

I feel your pain , good job !!