Deville 212 overdrive channel making Loud humming noise

On mine, the guitar input jacks get tarnished and causes all kind of interference and noise. Take a Q-Tip soaked with WD-40, run in down into the jack and brush up and down. Don't overlook the filter caps as they are a common cause of noise. You need a capacitor checker (the older tube type) to thourghly check those out.

It doesn't happen often but I suspect that the high gain input jack is defective. With nothing plugged into either input jack part of the signal is grounded and there should not be any noise. It might be that plus a noisy preamp tube. Try swapping the first two tubes to see if there is less noise. Carefully bang your fist or use an insulated tool's handle to hear if the noise changes. It might be an intermittent solder connection as well.

Unless the person that analyzed this problem used an oscilloscope and did detailed troubleshooting, I would NOT jump to the conclusion that aan op amp was blown BASED upon my looking at the schematic of the unit. There are MANY components involved with the overdrive channel, including relays and other transistors and components. The most probable caause would be that 1/2 of the V2 vacuum tube is burnt out. Test by swapping V1 with V2. If NOTHING works, then replace the tube that is NOW in V1 as the second section of it has a burnt out heater. Also a bad potentiometer for the OD channel would be a suspect. A VERY common problem is broken solder at pot terminals. Try plugging a set of headphones into the preamp output. See if you can hear sounds in bothe OD and clean channels. Note you will only hear sound in the LEFT headphone as the preamp out is MONO. MOST of the three op amp chips would NOT kill the OD signal if they were bad.

This is because your clean channel only runs through the pre-amp section, requiring an increased volume level to match that of the volume of the drive section which is overdriven by the pre-amp circuit. my suggestion is to use lower volume level on the clean channel of the amp. To get any volume boost you may need to match the two channels you could use a signal/volume booster or overdrive pedal between your guitar and amp input, switching it off and back on when you switch back and forth between channels.

One of the power supply voltages is bad... either a short or the regulator is blown. Follow my instructions for a previous poster:

http://www.fixya.com/support/t10013559-mackie_1604_vlz

These amps have a few issues. I would take to a tech, and go over many of the poorly soldered connections on the circuit board.

Hi. If the volume and drive levels are considerably low but you still hear a noise, you may want to consider trying a different guitar cable. The noise may be coming from a ground loop which is being amplified and overdriven by the amp itseld. I hope this helps. :-)

If it is just while turning the control, open the unit and squirt some CRC226 into the control through the slot where the leads go in. You can bend the plastic spout to get it to spray into the slot. While your at it, do the other controls as well. CRC 226 is available at Home Depot in the electrical dept. Blue can about $2.70. Use only the 226 product as there are others there.

The slider or the amps for channel 1 may have a problem.

Sliders do wear out.

Try shorting channel 1 input and see if that affects the noise. A hissing noise is probably a bad preamp chip. That is shop work at a repair facility.

it could be your guitar pickups. try using another guitar or getting your pickups waxed at your local music store. also if your playing in a small room kind of loud, or if your using single coil pickups (like fender statocaster pickups) you will definitely get a feedback noise. if that does not work let me know.