Steve Exton

If the nature of your problem is just the output levels of your different basses, then the simplest solution would be to adjust the output levels of the instruments to all be the same. Because it seems that some are passive and some active, this will have to be done in a passive manner to suit the passive basses.

Find the "quietest" bass on maximum volume, and adjust the volume controls on the others to match this volume level. Now measure the volume pot with a multimeter between top to centre and between centre to ground. Then get a new volume control of the value of the measurement between centre and ground and a resistor of the value of the measurement between top and centre. Replace the volume control with the new one, and wire the resistor between the wire that came from the top of the old volume control and the top of the new volume control.

What this mod will do is effectively restrict the maximum volume on the louder basses to the level of the quietest. Remember, the vaules of the new parts you buy don't have to exactly match the measurements, you just have to be close.

Hope this makes some sense. There are other things you could try such as adjusting pickup heights etc which will also change the output levels, but may change the sound too.

A word of caution! If you wire up the pots "backwards", then the audio taper on the pot will be incorrect. With logarithmic taper (or audio taper) pots, the half way mark on the pot is not half of the resistance, but about 20% of the resistance from one end and 80% from the other. On a left handed guitar, if you want to wire the pots up left handed (ie anti-clockwise rotation to increase volume) then you will need to use anti-logarithmic taper pots, or pots with a "backwards" taper.

allright...i forgot my camera but it doesn't matter. these guys were very accomodating. the mic is an old electro-voice model 664 and unk seems to have nailed it. stamped on one side is the following: "impedence changes are made on the cord plug. plug shell and no. 1 contact are ground. contact no. 2 hi-z. contacts no. 3 and 4 160 ohm.

now, armed with that info can anyone tell me which of the 4 wires on the original cord can be attached to which three wires on a three prong cord to make it work in a modern PA? the female plug end that attaches to the mic is labeled 1 thru 4 so it will be easy to trace the wires.

i guess part of what i need to know is what the three wires on a modern mic cord are for and if it will work as a low-z mic. if so it would seem logical that i could atach ground to ground and then the two remaining wires to #'s 3 and 4.

thanks

Standard 3 pin cannon plug mic wiring is Pin 1 Gnd, Pins 2 & 3 balanced mic. I would try the following:-

4 Pin Plug from Mic 3 Pin Plug to Amp

1 --> 1

2 not connected

3 --> 2

4 --> 3

This would give you the low impedance balanced output from the mic into pins 2/3 into the amp, and the ground connected through.