Output voltage guitar preamp

[hpupo]

Hi

I am afraid i already know the answer for this question (that it has no answer) but what is the standard output voltage of a typical guitar preamp?
Basically i am designing a power amp and i am what kind of input sensitivity i should aim for....

thanks

[ChrisA]

Originally Posted by hpupo

Hi

I am afraid i already know the answer for this question (that it has no answer) but what is the standard output voltage of a typical guitar preamp?
Basically i am designing a power amp and i am what kind of input sensitivity i should aim for....

thanks

Basically just "line level". You don't normally see guitars have separate pre and power amps but many times you see an "effects loop", that would be close to what you are looking for, Very roughly the level is about what goes in and out of a pedal. One the order of about 1 volt peak to peak.

But most guitar preamps have so much gain that they can over drive the power section into square wave clipping. You'll need a master volume control in the power amp

Here are a few well test guitar power amp sections intended to be used with any of the preamp sections on the same site
AX84.com - The Cooperative Tube Guitar Amp Project

[nigelwright7557]

Input to an amp is usually 0db, which is around 2 volts peak to peak.
So a guitar pre amp should output somewhere around there.

[firechief]

Uhhhh-- by power amp, do you mean everything from the phase splitter on?

[firechief]

Nigels answer is a pretty good one. I dident want to throw out a number beacuse there are so many variables.

[hpupo]

actually all answers help me out a lot. I will shoot for 1.5rms and see what happens...not sure i can make that kind of gain with 6cg7, but still....
tks

[tubelab.com]

You don't normally see guitars have separate pre and power amps

There used to be, and still are dedicated guitar preamps on the market. I use an old ADA MP-1 "MIDI preamp" It has a line output jack for driving commercial sound reinforcement amps, and a low level output for plugging into the guitar jack of your favorite amp to use the MP-1 as an effects box. The MP-1 and others like it put out about 1 to 2 volts RMS on the line output jack. They will drive most tube amps just fine. I use mine with a SSE or a Simple P-P for a guitar amp. There is enough extra output to drive the power amp into overload for that "cranked to 11" sound.

Ampeg and other amp manufacturers made dedicated preamps for the same purpose.

I plugged it into a Crown CE2000 and the result was an absolutely deadly 1 KILLOWATT of screaming lead guitar. One channel was blown on the CE 2000 so I only got 1000 watts.