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Vintage threads from the first ten years

Re: Volume Pot Question

8/11/1999 2:10 PM
Gus	Re: Volume Pot Question The body moves as well as the strings, but I think it is a time delay effect. Take a delay and adjust it from 0 to 10ms 1 or 2 repeats, The ear brain system hears that as one signal with more energy. I have been reading alot about this it helps explain alot of things that we "hear"

8/11/1999 4:27 PM
Doc	Nickel wound strings seem to have a lower output than nickel plated steel wrapped strings. The nickel plated also seem a bit brighter than the pure nickel wound. This is only for the wound strings! The plain strings on both sets would be (should be) identical. Unless you make sure both guitars are strung with the same strings, and have the same scale length, then you probably won't be able to easily pin down why there's such a noticeable difference in output. One other thing, sometimes the type/brand of control pots can have an affect on the sound quality. I've encountered a few import guitars that were factory-fitted with a low grade of mini pot. No matter what we did with respect to pickups, tone caps, etc., the guitar with the mini pots (it was a fender '60s reissue strat from japan) didn't sound right. We had installed texas special pickups, but they seemed constricted. We changed the pots, and the problem was gone. The guitar sounded great, like it should. My theory on this is that the mechanical connection between the carbon resistance element and the solder lugs was electrically poor, possibly having some metal oxide rectifier characteristics which deteriorated the sound quality.

8/11/1999 4:27 PM

Doc

Nickel wound strings seem to have a lower output than nickel plated steel wrapped strings. The nickel plated also seem a bit brighter than the pure nickel wound. This is only for the wound strings! The plain strings on both sets would be (should be) identical.

Unless you make sure both guitars are strung with the same strings, and have the same scale length, then you probably won't be able to easily pin down why there's such a noticeable difference in output.

One other thing, sometimes the type/brand of control pots can have an affect on the sound quality. I've encountered a few import guitars that were factory-fitted with a low grade of mini pot. No matter what we did with respect to pickups, tone caps, etc., the guitar with the mini pots (it was a fender '60s reissue strat from japan) didn't sound right. We had installed texas special pickups, but they seemed constricted. We changed the pots, and the problem was gone. The guitar sounded great, like it should. My theory on this is that the mechanical connection between the carbon resistance element and the solder lugs was electrically poor, possibly having some metal oxide rectifier characteristics which deteriorated the sound quality.

8/12/1999 7:44 AM

Joe Fuzz

quote:
"Unless you make sure both guitars are strung with the same strings, and have the same scale length, then you probably won't be able to easily pin down why there's such a noticeable difference in output."

The guitars are the same scale length, I do know that much. Well, it sounds like I'm going to have to get a couple of identical packets of strings and go from there.

Thanks!

8/20/1999 2:13 PM
Joe Fuzz	Update Managed to snag a set of calipers from the graphics department at work. The two sets are indeed different gauges. The set on the louder guitar are Lights i.e. .009 .011 .016 .024 .032 .042 and on the Wilkinson guitar they are Extra Lights: .009 .011 .015* .024 .032 .040* I did buy both packets at the same time from the same sales clerk but it seems I got two different types. (It was a 2-for-1 sale, no less!) If they're different sizes, they may be different materials, too. At least now I know which gauge to purchase. Secondly, something Gus said has gotten me thinking. It's quite possible, maybe even probable, that the resonance curves of these 2 guitars are simply different. In other words, perhaps the pickups are doing their jobs equally well, it's just that guitar A may have a mid-range frequency boost whereas guitar B may have a flatter response.

8/20/1999 2:13 PM

Joe Fuzz

Update

Managed to snag a set of calipers from the graphics department at work. The two sets are indeed different gauges. The set on the louder guitar are Lights i.e.

.009

.011

.016

.024

.032

.042

and on the Wilkinson guitar they are Extra Lights:

.009

.011

.015*

.024

.032

.040*

I did buy both packets at the same time from the same sales clerk but it seems I got two different types. (It was a 2-for-1 sale, no less!)

If they're different sizes, they may be different materials, too. At least now I know which gauge to purchase.

Secondly, something Gus said has gotten me thinking. It's quite possible, maybe even probable, that the resonance curves of these 2 guitars are simply different. In other words, perhaps the pickups *are* doing their jobs equally well, it's just that guitar A may have a mid-range frequency boost whereas guitar B may have a flatter response.

9/7/1999 5:07 PM
Mikko Helin	Re: Volume Pot Question What kind of load to use with guitar pickups in general is an interesting issue. As you roll off the volume on typical Stratocaster (which is wired so that the centertap of pot is connected to pu) the load impedance will decrease, which changes the tone. Also there are some FX boxes which have quite a low input impedance, f.ex. the Fuzz Face, but the guitar still sounds good (I think the Zin is abut 1 k or so for the FF, but that's maybe the reason why you get the best tones of it only when you back off the volume pot a little). I think that the guitar PU also sounds flat and "clean" (almost too clean) if there's plenty of load (under 50kohms or so). The advantage is that there's also less noise, but if the load is too heavy, you just loose the sustain. It might be interesting to build an inverting op amp stage with an adjustable input impendance and try different input impedances (you also need the gain adjustment to compensate). Also if you use 250k pots and connect to a 1 M amp input, the total load will drop below 200k (and with 1 M pot to 500k). If you want to get rid of all of the load you need a hiZ preamp connected directly to the PU. Also LP style volume pot connection where the centertap is output will load the pu less when volume is adjusted. Anyway, if the max. load without preamp is about 500k, so a 10Mohms load with preamp might have some effects on tone (maybe worth the trouble of changing batteries every now and then). So, what kind of active electronics "sound good" for you? -Mikko

9/7/1999 5:07 PM

Mikko Helin

Re: Volume Pot Question

What kind of load to use with guitar pickups in general is an interesting issue. As you roll off the volume on typical Stratocaster (which is wired so that the centertap of pot is connected to pu) the load impedance will decrease, which changes the tone. Also there are some FX boxes which have quite a low input impedance, f.ex. the Fuzz Face, but the guitar still sounds good (I think the Zin is abut 1 k or so for the FF, but that's maybe the reason why you get the best tones of it only when you back off the volume pot a little). I think that the guitar PU also sounds flat and "clean" (almost too clean) if there's plenty of load (under 50kohms or so). The advantage is that there's also less noise, but if the load is too heavy, you just loose the sustain. It might be interesting to build an inverting op amp stage with an adjustable input impendance and try different input impedances (you also need the gain adjustment to compensate). Also if you use 250k pots and connect to a 1 M amp input, the total load will drop below 200k (and with 1 M pot to 500k). If you want to get rid of all of the load you need a hiZ preamp connected directly to the PU. Also LP style volume pot connection where the centertap is output will load the pu less when volume is adjusted. Anyway, if the max. load without preamp is about 500k, so a 10Mohms load with preamp might have some effects on tone (maybe worth the trouble of changing batteries every now and then). So, what kind of active electronics "sound good" for you?

-Mikko

9/8/1999 1:31 AM
Joe Fuzz	a 10Mohms load with preamp might have some effects on tone Mikko: I tried out a SHO with the guitar and did notice a distinct difference in tone. The SHO has an R_in~5Megs if I'm not mistaken. (If Zachary Vex happens by, he can verify/correct.) However, the pedal didn't equalize the tone (see below) so I didn't persue it. This whole question started because I had 2 guitars wired exactly the same way with the same style of pickups and pots but producing 2 different tones. When I made that post last month, I originally thought that the electronics on one of the guitars was giving me less output. I now think that the electronics are, indeed, identical. There was a difference in string gauge and possibly string material, but I'm now leaning towards the fact that the bodies are made of 2 different woods and have 2 different bridge styles. It seems that the construction materials of the guitars are giving me 2 different frequency response curves. Not different V_outs necessarily, but different frequencies are being emphasized so they sound different going into the same effects. It might be interesting to build an inverting op amp stage with an adjustable input impendance and try different input impedances (you also need the gain adjustment to compensate). It's an intriguing idea. I think in my case adding some sort of pre-effect eq might also be helpful. A 1:1 base amplification ratio with a slight frequency boost. Hmm...maybe I'll dig out the breadboard... Of course, it's also nice to have the different sonic options that 2 guitars give, too...

9/8/1999 1:31 AM

Joe Fuzz

a 10Mohms load with preamp might have some effects on tone

Mikko: I tried out a SHO with the guitar and did notice a distinct difference in tone. The SHO has an R_in~5Megs if I'm not mistaken. (If Zachary Vex happens by, he can verify/correct.) However, the pedal didn't equalize the tone (see below) so I didn't persue it.

This whole question started because I had 2 guitars wired exactly the same way with the same style of pickups and pots but producing 2 different tones. When I made that post last month, I originally thought that the electronics on one of the guitars was giving me less output. I now think that the electronics are, indeed, identical. There was a difference in string gauge and possibly string material, but I'm now leaning towards the fact that the bodies are made of 2 different woods and have 2 different bridge styles. It seems that the construction materials of the guitars are giving me 2 different frequency response curves. Not different V_outs necessarily, but different frequencies are being emphasized so they sound different going into the same effects.

It might be interesting to build an inverting op amp stage with an adjustable input impendance and try different input impedances (you also need the gain adjustment to compensate).

It's an intriguing idea. I think in my case adding some sort of pre-effect eq might also be helpful. A 1:1 base amplification ratio with a slight frequency boost. Hmm...maybe I'll dig out the breadboard...

Of course, it's also nice to have the different sonic options that 2 guitars give, too...

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