Silvertone 1432 Microphone Input

[misterc57]

Should the 1432 microphone input work with a guitar? The instrument input jacks work great. The mic input is very muffled, with the volume at 10 it is barely audible. I do not have a microphone with a phono plug to test this input.

Attached is schematic which shows a minor difference between the two inputs.

Thank you.

[Jazz P Bass]

Seeing that the mic input does not have the 68K grid resistor, I would tend to think that it would be louder than the other two inputs.

I would look at the tube circuit itself. Something is amiss.

[mozz]

Is this a original, a homemade build or something that was worked on before? If there are shorting jacks, that would be the answer as the schematic shows regular 1/4". The schematic also shows a J1 INPUT.

[misterc57]

All 3 jacks are standard. I will pull the chassis out and see what is going on.

Thank you

[Enzo]

The 68k and the 1 meg make a voltage divider, but only a tiny reduction. You have something wrong with that mic channel itself. Guitar should work just fine. The 68k are there so they can have the 6db pad on the lower gain jack, ala Fender.

[misterc57]

Working now. Replaced the bad 330K ohm resistor at the plate of the microphone input.

Thank you for the help!

[Jazz P Bass]

Uhmm.

330K, correct?

[misterc57]

330K resistor

Uhmm.

330K, correct?

Woops, typo. Yes 330K resistor. Thank you