Guitar pickup output voltage

[tomstuder]

I was recently looking for typical values of guitar pickup output levels. I didn't find that much information online and decided to do my own measurements.

For anyone interested, I posted the results here:

Electric guitar output voltage levels

[Jazz P Bass]

Nice work.
For amp testing, I always go with 100mv's.
Some of those higher voltages surprised me.

[Chuck H]

Nice work.
For amp testing, I always go with 100mv's.
Some of those higher voltages surprised me.

Since I rarely need input voltage of a known quantity I usually set up an amp the same as where it would just start to clip a guitar signal. Then I plug in and adjust my generator signal so the amp just starts to break up. Easy peezy. Unfortunately I've never measured it.

100mV is probably about right.

[J M Fahey]

Thanks a lot

Very useful experiment and posting.

FWIW as a "general purpose" signal to test an amp I use 100mV @ 440Hz or 1kHz (same as JPB) but for a thorough test I use 50mV to check whether it can be adequately driven by a single coil guitar and the preamp first stage "should" stand 1V RMS (at least 500mV RMS) to guarantee clean unclipped sound even for "loud pickups" used by "loud pickers" .

Which confirms tomstuder's findings .

Thanks again

[Chuck H]

Oh yeah, I forgot to say NICE WORK to tomstuder. Very useful info. I've done those measurements myself. but never cataloged the results for reference or posted them for the benefit of all. Welcome to the forum. Way to introduce yourself

[J M Fahey]

These are very useful measurements.

I often do them the other way: no big deal on Tube amps, with first triode typically fed around 250V DC , but a real problem in SS ones: typical Op Amps can not swing more than 30Vpp ... or less, some 24/25Vpp on most, so by definition max first stage gain for guaranteed cleans is around 10X ; although 20X is acceptable if preamp has Hi/Lo inputs , so I plug a guitar with humbuckers, clip scope to first Op Amp out and strum a couple loud open chords.

And 9V powered pedals usually can't handle any stage output beyond 6Vpp , so clean input stage gain can never surpass 3X .

Of course, in a Drive/Distortion pedal that is not a problem.

EDIT: even in discrete Bipolar or Fet preamps, roughly same limits apply, since a very common supply voltage is around 25 V , single rail ... which amounts to about same Vpp capabilities as typical Op Amps.

[Mick Bailey]

What's the load applied to the pickups by the scope?

[Chuck H]

What's the load applied to the pickups by the scope?

I don't know the exact answer but I expect it's small enough to be neglected for practical purposes.

[tomstuder]

What's the load applied to the pickups by the scope?

The specs of the scope say 1MOhm input impedance and an input capacity of 18pF. Probe attenuation was at 1X.