How do all the input and output Jack's work and what do they do on a crate bx80 bass amp

SOURCE: Changing the output Jack on 1985 Peavey Dyna Bass

If this has active circuitry, one of the wires is the cutoff for the power supply from the battery. The other two are black for ground and either white or red for signal.

Posted on Apr 23, 2009

SOURCE: Peavey 115 Low hum Low volume from input

The preamp section has a problem. It could be anything in the preamp but is OFTEN the input jack itself. They take a lot of abuse.

Also the insert jack contacts that forward the preamp to the power amp if no external FX are used can go bad.

Additional things are circuit board cracks caused by rough handling and also controls that have had the knobs mashed in which can destroy the potentiometers they are connected to.

Posted on Sep 22, 2009

SOURCE: Marshall MG100HDFX 100-Watt Amplifier Head. The

You'll have to take it in to get it repaired. From what you described it sounds like you blew the output stage out. You can't run from your speaker output jack into the input jack of another amp. You should go out of the recording out, line out, effects out or in the least case your headphone out. What happens usually is your output transformer short circuits due to a mismatch of impedances. It sounds like you still have a transformer though so you might have gotten lucky. You will need to take it in though. Sorry.

Posted on Nov 26, 2009

SOURCE: Crate bass amp bt220 limit led is flashing

You can reach the limiting IRRESPECTIVE of where the volume control is set when you have a guitar or other source that has HIGH output.

Guitars that have battery in them with internal amplifiers are an example of a high output guitar. Plain inductive pickups may require the volume control to be set at say 70% to reach limiting.

Please NOTE that the volume control is NOT linear, but is an "audio taper".

Limiting means you are probably driving it too hard. Many learn the hard way when speakers and thee power amp fail.

When the cone is driven too far beyond the pole pieces of the magnet, then the IMPEDANCE of the speaker becomes relatively low and can damage the power amp. The limiter tries to prevent this by sensing the current and or voltage and will back off the gain internally. This causes distortion when it happens.

Posted on Dec 14, 2009

SOURCE: Crate Bass Amp B100 - No sound.

Do you happen to have another speaker that you could hook up to speaker output? This would bypass the amps internal speaker and lf you get sound from that setup, it would mean either a jack failure or possible internal speaker problems. Please let me know.

Posted on Jan 24, 2010