Just gotta understand these meter readings for these HBs -- haha

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merkaba22

New member
I have three Gibson SGs, each with a coil tap yielding the following output measurements when the volume is on "10":

Hybrid -- 11.67K and 7.55K

Custom 85 -- 14.56 and 7.34K

Stock w/Bill Lawrence (HB-L / L-8) -- 13.22K and 6.67K:

I thought it would be revealing to see where the outputs are (in HB mode) when the volume is "7" or "4", for example, since those types of setting significantly alter tone/response, etc. -- that, at these lower "volume" settings, I thought I would see readings with a lower output, that might otherwise guide inform me on the benefits/sounds of lower output pickups, etc.

But on my OHM meter (Radio Shack "Auto-Range Digital Multimeter) is get very odd/high numbers (I know, there are some jokes in there):

Hybrid -- 114.0K and 35.02K

Custom 85 -- 104.4 and 28.48K

Stock w/Bill Lawrence -- 95.1K and 117.5K.

Can anybody explain what these readings are and by what alternative method could I see readings of lower output as I reduce the volume settings ...?
 
Re: Just gotta understand these meter readings for these HBs -- haha

how are you measuring? at the pot lugs or at the output jack?

what setting or range do you have the multimeter on?
 
Re: Just gotta understand these meter readings for these HBs -- haha

I am connecting the leads from the Multimeter to a short guitar cord plugged directly into the jack for each instrument the same way for all measurements -- the Multimeter is set for OHMs, etc. (I have been using this unit for over ten years and its always been good/accurate) .... bizarre that it reads correctly for both HB and single coil selections but only at full output, ie. on "10"....
 
Re: Just gotta understand these meter readings for these HBs -- haha

just checked mine and it does the same. until someone with a far greater technical knowledge has an answer, all I can think of is that it seems the resistance is being measured - hence DC Resistance. the more you cut off the flow via the pot, the more resistance there is. ???
 
Re: Just gotta understand these meter readings for these HBs -- haha

darthphineas said:
just checked mine and it does the same. until someone with a far greater technical knowledge has an answer, all I can think of is that it seems the resistance is being measured - hence DC Resistance. the more you cut off the flow via the pot, the more resistance there is. ???
Click to expand...

Yea, yea -- pretty wild, since these are values we reference in choosing/defining PAFs over Jeff Becks, etc. ... and Bill Lawrence defines in terms of "Henries" or something, right ... what's that about? Really, interesting stuff -- still, I would love to know what output is associated with lower "volume" knob settings ...
 
Re: Just gotta understand these meter readings for these HBs -- haha

You can't measure this way. With the volume pot on "10", you have the pickup and pot in parallel. (The reading will be close, but slightly lower than the pickups actual DCR.) As you roll the pot down, (watch your meter), the resitance will rise as you're adding the part of the pot thats "above" the wiper into the reading. As you continue to turn the pot down, you'll see the resistance glide back to zero as the wiper approaches ground.

DCR, as a measurement of output, is completely irrelevant while the pot is in the circuit. ;)
 
Re: Just gotta understand these meter readings for these HBs -- haha

all I can think of is that it seems the resistance is being measured - hence DC Resistance. the more you cut off the flow via the pot, the more resistance there is. ???
Click to expand...

Yep, that's what's happening. For normal electrical circuits in general the more resistance the less the current flow. That's how the volume pot works. DC resistance is an indirect way of measuring a pickup's output because there is a pretty direct relationship between more coil wraps (longer wire) and more resistance. It's the extra coil wraps that increase pickup output, not the resistance.

As you lower the volume knob you're injecting more resistance into the guitar circuit so you're getting higher readings on the multi-meter.
 
Re: Just gotta understand these meter readings for these HBs -- haha

ArtieToo said:
You can't measure this way. With the volume pot on "10", you have the pickup and pot in parallel. (The reading will be close, but slightly lower than the pickups actual DCR.) As you roll the pot down, (watch your meter), the resitance will rise as you're adding the part of the pot thats "above" the wiper into the reading. As you continue to turn the pot down, you'll see the resistance glide back to zero as the wiper approaches ground.

DCR, as a measurement of output, is completely irrelevant while the pot is in the circuit. ;)
Click to expand...

Great and true observation and that is what I was trying to describe, and thank you -- but the remaining, and main question, is how you can determine the probable outputs at various "volume" levels as a reference for the outputs of other pickups we tend to be interested in, etc.
 
Re: Just gotta understand these meter readings for these HBs -- haha

You can't do what you're trying to do the way you are trying to do it ;) Resistance of a single coil or series wired humbucker pickup in isolation is a pretty good indicator of output, but add it to a guitar circuit and resistance goes from positive to a negative correlation with output.
 
Re: Just gotta understand these meter readings for these HBs -- haha

merkaba22 said:
-- but the remaining, and main question, is how you can determine the probable outputs at various "volume" levels as a reference for the outputs of other pickups we tend to be interested in, etc.
Click to expand...

A volume pot is wired as a voltage divider. The ratio of division is independent of the voltage applied. For example, if the volume pot is set for half voltage output, it will always be half for any voltage, ie., any pickup that's connected. So, 80% output will always be 80% output. You don't need to calculate "probable" output.
 
Re: Just gotta understand these meter readings for these HBs -- haha

robrob2 said:
You can't do what you're trying to do the way you are trying to do it ;) Resistance of a single coil or series wired humbucker pickup in isolation is a pretty good indicator of output, but add it to a guitar circuit and resistance goes from positive to a negative correlation with output.
Click to expand...

Yea, yea -- that's apparent, thank you .... but the initial and remaining question:

Is how can you find out what the equivalent output for the instances, when, say, a HB measuring 14.0K OHM resistance (maxed at "10") is set to "7" or "4" on your guitar's volume knob? What measuring system would you use?

And how would a PAF style PU @ 9.0 K OHMS at 10 compare, etc. in the prior instince?

What effect does a 50's wiring have where the volume control is equally directed to cleaning up a pickup/amp response, etc.?
 
Re: Just gotta understand these meter readings for these HBs -- haha

merkaba22 said:
. . . how can you find out what the equivalent output for the instances, when, say, a HB measuring 14.0K OHM resistance (maxed at "10") is set to "7" or "4" on your guitar's volume knob? What measuring system would you use?
Click to expand...

You would use a voltmeter or an o'scope. You would have to measure the actual voltage. But once you knew the initial voltage output of the pickup, you could calculate the voltage at any pot setting by measuring the pots resistance between the wiper and the ground lug and just using the voltage-division formula. You would, of course, need to pre-measure the pot out of circuit, to get its actual resistance reading.
 
Re: Just gotta understand these meter readings for these HBs -- haha

I was afraid it might be headed that way, but these guys are correct when they say that resistance is not the way to determine output. it's one of the more common misconceptions... right up there with a DD is just a JB with a ceramic.
 
Re: Just gotta understand these meter readings for these HBs -- haha

So .... how can you find out what the equivalent PU at max output for the instances, when, say, a HB measuring 14.0K OHM resistance (maxed at "10") is set to "7" or "4" on your guitar's volume knob without all the math; i.e., has no one sorted this out in the past 60+ years?
 
Re: Just gotta understand these meter readings for these HBs -- haha

sounds like you might be best served calling SD tech support. this is just a forum for end-users.
 
Re: Just gotta understand these meter readings for these HBs -- haha

Most people are just happy to know how it sounds quite frankly. Like "at 7 I get a good stones-y crunch and at 4 its just a bitey clean". They have really no use for exactly what output is coming from the pickup at these points......that type of detail is best left to the lab-coat brigade.

Also - just remember that the taper type will affect this too, as will whether you've got it 50's LP wired.
 
Re: Just gotta understand these meter readings for these HBs -- haha

AlexR said:
Most people are just happy to know how it sounds quite frankly. Like "at 7 I get a good stones-y crunch and at 4 its just a bitey clean".
Click to expand...

Exactly ... but we have a pile of PUPs available with an output rating system with references to resonant peaks; and as crude as that system you may indicate it is, it would be great to take it a step higher, right?

Honestly, if anyone asked MJ, for example, I feel she'd know what was meant and what they were looking for -- it would be so cool to have that body of experience/knowledge available in a more articulated fashion than ... fwiw
 
Re: Just gotta understand these meter readings for these HBs -- haha

This thread is a prime example why it is so bad to take D/C resistance as "output". It leads to then completely mix up what other components that have resistance stand for.

Nobody would say that my volume pot has 25x more output than my humbucker because it is 500 KOhm while the pickup only has 20 KOhm.
 
Re: Just gotta understand these meter readings for these HBs -- haha

Wow, I've got to install a 500K volume pot in my Telecaster to boost my amp into overdrive. Do they make 600k pots? ;)
 
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