Tube Amp Archive

Yes you can use the unused 4-ohm tap. Yes you can simply not connect the shorting tab. These amps are a little funny because they were cheap-o "student" amps, had really small OTs and didn't do bass frequencies well. That's a blessing in disguise because SE amps do exhibit 60Hz and 120Hz hum at the...

How much do you want it to sound like a stock Vibrochamp? Fender took the feedback signal from a 4-ohm tap. The 8 will provide more feedback and the 16 more still. You can achieve original performance by adjusting the feedback (2K7) or shunt (47R) resistors. More feedback will reduce output and "ti...

Wikipedia gives a reasonably good description of NFB. http://en.wikipedia.org/wiki/Negative_feedback_amplifier More technical here: http://www.aikenamps.com/NegativeFeedback.htm http://www.aikenamps.com/GlobalNegativeFeedback.htm If you want to wire for both 8z and 16z there are two choices. One is...

uhm that's the feedback line and you put it on 1 output only ! just check the original fender schematic and whether you put it on the 8 or 16 ohm tap i'd go for the 16 ohm tap since it's the highest output ohmage of you tranny! i hope you didn't really mean like soldering two wires to the different...

I'm building a Triode Vibrochamp clone. The schematic calls for two 8ohm speaker outputs in parallel. I want to wire it for an 8 and a 16ohm jack as I have both impedance cabs (I have an OT with the proper taps). Theres a portion of the preamp wired to both output jacks, its the pink wire in the lay...