Two Preamps to One Power Amp

[jeff]

How would you wire the two preamps to a mono power amp so you could use two guitars, and the tone and volume of one won't affect the others?

Would you have to add another tube?

http://www.el34world.com/projects/images/stereopreampschematic.gif

[PRR]

Two 470K resistors.

[stingray_65]

A 1 meg linear pot would let you pan between pre amps. hook the A side to one lug, Bside to the other and wiper to your power amp.

set in the middle it would be the same as 2 470K resistors as PRR suggests

Ray

[sluckey]

Is this negligable in the real world appilcation?

yes. The 470K resistors will provide adequate isolation between channels if connected at the wiper of those output pots.

[jeff]

Oops I accidentally removed my post after Sluckey's reply. This is what Sluckey was responding to.

I was just asking if the two 470K resistors form a voltage divider and as one channels volume is almost off(distortion-high gain, low vol) the other channel would have a 470K/470K voltage divider and when it was full on(clean-low gain, high vol) the first channel would have a divider of 470K/ (1meg parallel with tone setting resistance to ground). Would one channel have to adjust its volume every time the other went form clean to distorted or changed tone settings. and if this was negligable.

[sluckey]

You could do that. I'd prefer to just connect the guitar to an AB/Y switch and connect the switch to both channels. That way you can have either or both channels at the tap of a foot.

[jeff]

I was thinking of using a stereo jack and a switch that puts A on ring B on tip or vice versa. When a standard plug is in the ring would be grounded so you could switch channels. If I used a stereo jack on my guitar I could have a different channel for each pickup or use an A/B box that sends the input to ring or tip. In that case the switch would just reverse channels.