Average output in millivolts

Status
Not open for further replies.

Soccerman

New member
Hi
This post has absolutely nothing to do with tone. May have nothing to do with impedance - although you real engineers out there might have to explain to me that it does.

All I need to know is what is the average ballpark output, in millivolts, of a Hot Rails pickup when you pluck a string. You can pick whatever string you want - fatty or skinny. I've always thought it would be about the same as a microphone, and I thought that to be 10 mV or less. But I read a post elsewhere in this forum that indicated that the initial primary attack could be as high as ONE VOLT, quickly dropping to 350 mV and decaying from there.

That's a big difference from my guestimate of 10 mV, LOL.

So, which would be closest - me or this other guy? Remember - I'm only interested in ballpark averages, so an answer like "Yeah, you're probably closer to 400 mV than 10 mV for the initial attack for a HotRails output" would be just fine. All I need the info for is to buy a meter for a steampunk cigar box guitar I'm building. Clearly a meter with a scale of 1-10 mV would be useless if the initial attack turns out to be more like 700 mV. It doesn't even need to be accurate - all I want is the effect of a needle flicking up and down when I pluck a string. It's purely for visuals.

Actually, if it can be done, I would rather do it with a VU meter than a mV meter as the one I'm looking at has a very cool steampunk vibe. But a VU meter seems to need a driver board requiring 12 volts plus and obviously I don't want to be messing around with power supplies. I suppose if I could find a driver needing only 9 volts I could run it off a battery that is turned on when the plug is inserted like my active bass. But it's for my kid and he would just leave it plugged in all the time.
Maybe there is an input resistor or something similar built into the VU meter that I could change to get it to flicker? Remember - it doesn't have to be accurate; I'm just after the visual effect.

If you have a better idea for using a VU meter passively, I'm up for whatever you've got in your bag.
Thanks for your time.
Phil
 
Re: Average output in millivolts

I am not sure single sized humbuckers were ever measured...the closest I think was this thread, which is about humbuckers.
 
Re: Average output in millivolts

Yep. Guitar pickups produce significantly more output than microphone. Even lowest output vintage pickups produce above 100 mv. That's why recording gear have separate inputs for instrument and microphone level.

There is (questionable) chart of average output of SD pickups in this forum you can somewhat easily find with search. The outputs vary from under 200mv to 1,3 V.

EDIT: That's the chart Mincer posted. Outputs are even more out there than remembered... DiMarzio page lists mv of their pickups, I think there standard singecoils are in 100-300 mv range. but there is no stadard way to test them so they're all incomparable.
 
Last edited:
Re: Average output in millivolts

So - I thought we were all done here. Not so fast!!!

I thought I would run a quick test on the output from my bass, just for the experience. It's an active bass, so it probably isn't going to be an apples to apples comparison, but I just wanted to see what I got on the meter.
Surprise surprise - I got nothing. Zilch. Nada. No volts. No millivolts. I tried a digital meter and an analog one. I tested the cable that I knew was good. I tried AC volts and DC volts(!).
So now the question is the simplest one if you please - why on earth not?
Thanks
Phil
 
Re: Average output in millivolts

Hi
Plug the bass in, take a digital meter set to AC Volts (200 volts is smallest scale, but it should still register something, I would have thought) and touch the test leads to the other end of the cord and hammer away. I also tried it with an analog meter with a scale of 10 volts AC. Again, I would have expected it to at least flicker.
Just to make sure I was still in the correct universe, I plugged it into an amp. Works fine.
Thanks
Phil
 
Re: Average output in millivolts

The amount of time you'd achieve over 1 volt is extremely brief, it can last for as little as a single cycle. The meter probably expects a sustained AC voltage in order to measure accurately. You have to record the string pluck with a DAW and look at that voltage peak that way, or plug into an oscilloscope with persistence, and see what it peaks out at when you pluck the string.
 
Last edited:
Re: Average output in millivolts

Ah - yes. That could well be the reason. We have a bunch of scopes at work and guys who can use em - I will probably ask next week.
Let's consider this post closed then - but I do have another posted about VU meters if you would care to read it.
Thanks everybody
Phil
 
Status
Not open for further replies.
Back
Top