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I have some questions about line-outs/effects loop/signal splitting in a preamp.

The main thing I'm trying to understand is how to best approach a bass preamp design where I'll have a regular unbalanced output to go to a power amp, and also a balanced output (Jensen xformer), possibly a headphone output whose level is variable.

I want to make sure that the tone will remain consistent whether I'm using one or all outputs, which I imagine meands keeping the impedance of the preamp itself constant.

How would I split the "signal" so that the impedance of the circuit (and therefore tone) remains the same? Do I need a buffer circuit for each output? Most schematics I've seen take a line out from the speaker side of the OT, but I won't necessarily have a power amp.

Will using a single buffer then feeding all the outputs work? Is "splitting" accomplished in the same way as summing, using mixing resistors?

Thanks,
Chris

Hi, Chris:

If you want to add an balanced output transformer at the preamp. This is a better way to use one preamp. to drive a few power amps. If the quality of the transformer is good, it wouldn't affect any sound reproduced.

Usually the industrial musical equipment always equipped a balanced output on the preamp. standard 600 ohms impedance. The input impedance of a power amp. is 15K ohm. Thus, a single preamp is capable of driving 10 power amps.

Guitar amp. is defined as industrial equipment, sometimes may connected with the amplifier system in a concert hall. the design of a guitar amp. is capable of doing this job.