I had an issue with GK years go. I have a first version of the 1001RB purchased new. I rewired a 4X10 with a Fostex/Foster horn to use the biamp function. The tweeter hissed, but no sonic sound from it. GK wanted it back to repair it, so I shipped it to them.
6 weeks later, I got the amp back. The tweeter amp still didn't work but they said they upgraded the amp, modifying the turn on transient function to current specs. I was livid.
I had a service manual, and called them and got permission to fix the tweeter amp without voiding the warranty. I found it in 10 minutes...a coupling cap before the tweeter amp was way out of spec. It passe 10kHz but nothing below it. GK only tested at 10k that's why they missed it. The crossover point is 5kHz.
I found some disturbing things in the amp. They had replaced a dual op amp, adding a socket. GK techs severely burned the circuit board. They had also replaced a couple components, but didn't take the circuit board out to do it right. They heated up the resistor legs from the top...pulled out the resistors and tried to solder the new ones in from the top.
Underneath there were solder blobs dripping from the pads, almost touching the chassis...like stalagmites. I sent them pictures of their extremely crappy work.
GK apologized. They said they had a tech instructional meeting on proper rework and soldering techniques. They changed their tweeter amp testing to include testing at the crossover frequency.
Meanwhile, I had a new amp with a burned board that I had to repair.
I'm sure they have tightened up their repairs...or at least I hope they did, but it really left a bad taste in my mouth concerning GK. There are good companies out there. I don't consider GK in that group.
My GK went down three years ago. (not GK's fault...a glass of water fell off a shelf at a gig, and dumped into the fan vent on top.) I bought a PF-500. I love the Ampeg so much, I still haven't fixed it. I will someday. I won't send it to GK to fix.
6 weeks later, I got the amp back. The tweeter amp still didn't work but they said they upgraded the amp, modifying the turn on transient function to current specs. I was livid.
I had a service manual, and called them and got permission to fix the tweeter amp without voiding the warranty. I found it in 10 minutes...a coupling cap before the tweeter amp was way out of spec. It passe 10kHz but nothing below it. GK only tested at 10k that's why they missed it. The crossover point is 5kHz.
I found some disturbing things in the amp. They had replaced a dual op amp, adding a socket. GK techs severely burned the circuit board. They had also replaced a couple components, but didn't take the circuit board out to do it right. They heated up the resistor legs from the top...pulled out the resistors and tried to solder the new ones in from the top.
Underneath there were solder blobs dripping from the pads, almost touching the chassis...like stalagmites. I sent them pictures of their extremely crappy work.
GK apologized. They said they had a tech instructional meeting on proper rework and soldering techniques. They changed their tweeter amp testing to include testing at the crossover frequency.
Meanwhile, I had a new amp with a burned board that I had to repair.
I'm sure they have tightened up their repairs...or at least I hope they did, but it really left a bad taste in my mouth concerning GK. There are good companies out there. I don't consider GK in that group.
My GK went down three years ago. (not GK's fault...a glass of water fell off a shelf at a gig, and dumped into the fan vent on top.) I bought a PF-500. I love the Ampeg so much, I still haven't fixed it. I will someday. I won't send it to GK to fix.