Peavey CS800 Questions

[tdlunsfo]

To confirm, this is the old school amp with the two volume knobs in the front and the chips on the boards. Can someone tell me about this amp? Customer is saying that one channel doesn't work (it's been a few years since it was plugged in). I plug it in, connect my MP3 player to the power amp in, try both channels and they both work. Question is.. this is a big heavy duty amp but the sound isn't extremely loud like I expected. To clarify, with everything cranked it gets plenty loud but I just expected more. The Peavey XRD680 I just fixed was louder.

Is this because I am driving it with an MP3 player and/or using an old tube amp speaker? Or maybe this amp simply isn't extremely loud as it's weight suggests it should be? I'm struggling to find something to fix on it. I am showing about 76v on the power amp collectors. Seems that is around the designed rail voltage. No shorted/open transistors. Maybe I need to place it in bridge mode?

[Enzo]

Amps are not loud by themselves, they have a maximum power output, but they also have a sensitivity spec. Just because it is an 800 watt amps doesn;t mean it puts out 800 watts every time the volume control is maxed. If your signal source is not up to the task, the output is reduced. Also, the CS800 is a straight power amp, while the XRD680 is a powered mixer, meaning it has power amps but also preamps (the mixer part) as well. preamps boost signal into the power amp.

[tdlunsfo]

Thanks Enzo. I don't have much experience operating power amps so I figured it had to do something with my setup. The crossover/balance transformer connectors on this amp is interesting. I noticed I had to have these in place in order to use a lo-z mic. Was this amp supposed to have 4 of these? This one only has 2. Anything else I need to check on this before I send it back? Common issues/failures? It was really dirty and I gave it a good cleaning. Pretty much it at this point.

[Enzo]

The top panel of the amp should show a block diagram of those 11-pin connectors.

There are crossover modules, transformer modules, and jumper plugs.

To use the low Z inputs you need the transformers. If you use a jumper plug instead of the transformer in the transformer socket, then the XLR jacks work, but only for unbalanced signal. If that 11-pin socket it empty, the XLR jacks do nothing.

To use the regular 1/4" INPUT jacks, you do not need anything plugged into those sockets.

The crossover jack is there for the crossover modules. Using one means plugging full range signal into the CROSSOVER IN jacks, and the crossover module splits it onto highs and lows, which come out the CROSSOVER OUT jacks. Then those highs and lows would be patched into the regular input jacks of each channel.

If you put a jumper plug into the crossover socket, then all that happens is you can use the crossover input jacks same as the regular inputs. No particular advantage to that.


SO:
To use the regular inputs, no jumpers/modules are needed. To use the XLR input you need a jumper in the crossover socket and either a jumper or a transformer in the transformer socket. A transformer there allows balanced input, a jumper ther allows unbalanced input.

[tdlunsfo]

Enzo you are a living, breathing Peavey encyclopedia. It's kind of like a superpower... for music equipment.

[Enzo]

Nah, I am like the Encyclopedia Britannica. I am out of date, and mostly gather dust on the shelf.

[tdlunsfo]

Haha. Well played sir.. well played.