First off thanks for any help you can offer. I have a Ampeg B500DR bass amp that won't get put out any bass guitar sound. When I turn up the volume the fuzz gets louder but no signal output. There is a relay I was tapping on and after a few taps I resistor in the power section fried. I attached the block diagram but could really use the schematics if anyone out there has them.
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What does the DVM (volt-ohmmeter) say the speaker leads read on the low ohms scale? Should be 4 ohms or above. Calibrate the meter with a known resistor, when meter batteries go weak this is the first scale to read the wrong numbers.
If that is okay, how old is the amp? Does it have IC's on the heat sink or Transistors. How old are the electrolytic capacitors? (25 years is too long).
If that is okay, how old is the amp? Does it have IC's on the heat sink or Transistors. How old are the electrolytic capacitors? (25 years is too long).
Well, if your speaker or wires are not messed up, (test above) check to see if there is DC coming out of the speaker hot terminal on and idle. If so, one or more output transitors are bad. Then if none of that, check your power supplies that they are about 80% of the capacitor rail voltage. Checking rail voltage while playing into 4 ohm resistor (watt rating >amp rating) would be a better test.
I’m having the EXACT SAME Problem out of my B500DR. I can plug into the power amp out and get sound....but if plugged into the input it cracks and pops....but you can tell the power section is working.
I’ve done all the **** noted above and nothing has happened for the better. If Ampeg weren’t so douchey thinking everyone’s out to steal their designs the schematics for this would be up. Because this is the only “digital” amp they ever made and haven’t made one since. I’m sure there’s a good reason why.
I’ve done all the **** noted above and nothing has happened for the better. If Ampeg weren’t so douchey thinking everyone’s out to steal their designs the schematics for this would be up. Because this is the only “digital” amp they ever made and haven’t made one since. I’m sure there’s a good reason why.
Hi, just a suggestion. Assertions like this are not helpful. The B500DR was from the SLM Ampeg era, design from 1998, and updated as late as 2006. SLM sold the Ampeg line to Loud Technologies a bit later. They are the Mackie people. And even more recently Loud sold the Ampeg line to Yamaha, the current owner. Why does that matter? If you contact Ampeg today asking for drawings, you are talking to a place two companies removed from the one who made the amp. Yamaha doesn't care if you steal the design, as they didn't design or make the thing. The schematics are available on the internet. A 20 year old design is not a hot property. Also, this is not a digital amp. Only thing "digital" about it is the groovy LEDs.
I would post the schematics here, but it is 2,3M and that is way over the file size limit for this board.
I had no idea about who they were owned by. I never even knew the company sold to another company. The only reason I called them douchey is because I haven’t been able to locate hardly anything about this specific model. Very interesting that Yamaha is the current owner. I just thought they were being a bit overprotective with their schematics from people that aren’t “specialists”.
I’m just trying to figure out why my head puts some sound, but won’t put sound out that I’m able to jam with.
I’m just trying to figure out why my head puts some sound, but won’t put sound out that I’m able to jam with.
I see the SLM stuff all over the board, and inspected by, etc. those LED’s are pretty cool, and the fact I can program 4 channels for 2 basses is nice. (It looks to even have a bias control, something I’ve never seen in a SS amp.
Maybe you could email me the schematics? I used a Yamaha bass (and absolutely loved it) for over 10 years. But I think that’s when they started making Ampeg in Korea or Vietnam. I just know not in America anymore.
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