How do I actually measure the output of my bass?

[Owen]

As in actual Volts (or whatever I am meant to say here!).

I am trying to sort out stuff and would like to know in numbers whether one of my basses is SUPER HOT on output or whether my problem is elsewhere. Do I put a multimeter across a jack plug?

TIA.

[paul_5]

Yes, a multimeter across the lead (red to tip, black to sleeve) will give you the output in millivolts as you play, but will fluctuate wildly with playing dynamics - the harder you hit, the greater the reading. 
 

you could also put your multimeter across the hot and ground connections on your pickup(s) too - this time measure the dc resistance of the pickup. Generally a jazz bass pickup will be anywhere from 6.5 to 8 ohms, but I’ve seen some up at 11. There’s more to it than this, but it’s a good indicator that a pickup is either ‘hot’ or not.

[ikay]

Here's vid demonstrating output measurement with a multimeter. Jump to 4m 30s if you want to skip the preamble.

 

[Owen]

You guys! Thanks

[MoonBassAlpha]

A digital storage oscilloscope would do a good job

[Baloney Balderdash]

If you are just interested in comparing it's output to other of your basses you could simply record the different basses if you got a DAW installed on your computer and a sound interface, just using the same settings on whatever gear you eventual use between the bass and sound interface (like a preamp, EQ e.t.c), and playing the exact same with about an equal amount of force behind your picking on the different basses you want to compare, that way you would get both a dB measurement of the difference between the output of your different basses and you would get a visual idea of it by comparing the graphic representations of the recorded bass signals in your DAW.

Edited December 4, 2020 by Baloney Balderdash