Installed a new LM4765 power amp chip and .... nothing. 1kHz sinewave input, crank the knobs all the way and just get a small distorted signal at the output. Hmmmm.
Ooops. The LM4765 tab was supposed to be isolated from ground. Sure enough, there is a little plastic isolation bushing lying on my workbench from the disassembly, it has been so many months since I took it apart I forgot the bushing. So I killed the new amp chip. Slap forehead.
Ordered another new LM4765, installed properly and .... it works! Then I had to download a Line 6 Pilot's Manual to figure out what the buttons and knobs do, but anyway its all working fine now. I had been so frustrated with this repair, I was ready to toss it.
But now, I will keep it around for a while, it really has decent sound. I would give high marks to the clean and twang models, the blues and crunch are OK, but not so much to the other two models. You can access all of the amp's features from the front panel, by pressing various combinations of buttons, but that's not something you want to mess with on stage. If you don't have the manual printed out, every time you change a model the knobs settings are reloaded from the model in memory, so looking at the knobs will not tell you where things are set. To find out, you have to press TAP, spin the model knob to let it know what you want to find out, then spin each tone and effect knob one at a time until LEDs tell you to stop spinning, then you know where the model equals the knob setting. So like a lot of digital amps, you really need the footpedal thing if you are going to do a lot of model changing.
While I was waiting for parts to fix this amp, I acquired another Yamaha DG-80, it arrived on the same day that I got the Line 6 Spider working. After fooling around with the Line 6 for a while, I really appreciate the motorized pots on the Yamaha, when you change the model the software runs the motors, turns the pots to the new settings. The Yamaha is just easier to set up, easier to store your custom models in memory, it stores more, and basically they just did a much better job of modelling; the Line 6 definitely has limited character, with the Yamaha you can find more of everything.
Ooops. The LM4765 tab was supposed to be isolated from ground. Sure enough, there is a little plastic isolation bushing lying on my workbench from the disassembly, it has been so many months since I took it apart I forgot the bushing. So I killed the new amp chip. Slap forehead.
Ordered another new LM4765, installed properly and .... it works! Then I had to download a Line 6 Pilot's Manual to figure out what the buttons and knobs do, but anyway its all working fine now. I had been so frustrated with this repair, I was ready to toss it.
But now, I will keep it around for a while, it really has decent sound. I would give high marks to the clean and twang models, the blues and crunch are OK, but not so much to the other two models. You can access all of the amp's features from the front panel, by pressing various combinations of buttons, but that's not something you want to mess with on stage. If you don't have the manual printed out, every time you change a model the knobs settings are reloaded from the model in memory, so looking at the knobs will not tell you where things are set. To find out, you have to press TAP, spin the model knob to let it know what you want to find out, then spin each tone and effect knob one at a time until LEDs tell you to stop spinning, then you know where the model equals the knob setting. So like a lot of digital amps, you really need the footpedal thing if you are going to do a lot of model changing.
While I was waiting for parts to fix this amp, I acquired another Yamaha DG-80, it arrived on the same day that I got the Line 6 Spider working. After fooling around with the Line 6 for a while, I really appreciate the motorized pots on the Yamaha, when you change the model the software runs the motors, turns the pots to the new settings. The Yamaha is just easier to set up, easier to store your custom models in memory, it stores more, and basically they just did a much better job of modelling; the Line 6 definitely has limited character, with the Yamaha you can find more of everything.