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Vintage threads from the first ten years

Re: Volume control Tone

6/2/1997 6:16 PM
Francis	Re: Volume control Tone Dave, Thanks for your help! Francis

7/29/1997 12:42 PM
Ryan	hi. i did this mod as you suggested with the .001mf and a 150K res. it works great, just what i was looking for. could you explain how different caps & res values would change the end results? thanks ryan

7/30/1997 6:47 AM
Dave Harris	Mark Hammer pretty much explains the effect of different cap values in his post of 6-19-97 in this thread. The cap on its own works quite well for moderate reductions in volume but if you reduce the vol a lot it tends to over compensate. The resistor attempts to prevent this by loading the pickup more as the vol is turned right down to reduce excessive HF. It works because the pickup is inductive and its output impedance therefore increases with frequency.

7/30/1997 6:47 AM

Dave Harris

Mark Hammer pretty much explains the effect of different cap values in his post of 6-19-97 in this thread. The cap on its own works quite well for moderate reductions in volume but if you reduce the vol a lot it tends to over compensate. The resistor attempts to prevent this by loading the pickup more as the vol is turned right down to reduce excessive HF. It works because the pickup is inductive and its output impedance therefore increases with frequency.

6/19/1997 6:33 PM
Mark Hammer	Actually expensive guitars DO include such mods. I received an e-mail from John Suhr (former luthier to Mark Knopfler, among others, and currently employed by the Fender Custom Shop) describing exzactly the circuit depicted here (although I seem to recall it was a 680pf cap and not 1000pf). You'd be surprised at what expensive guitars lack in the way of electronics, though. I've harped on it before, and will harp on it again here: front and rear pickups need different tone controls, because you use the tone control to do different things with them. So far, so good. Do you think that a Les Paul or even costlier instrument with front and rear tone/volume circuits would install different tone control wiring for front and rear pickups, even though the cost difference is absolutely negligible? Not on your life! Volume and tone control circuits have remained fairly stagnant for the last 45 years. Get hold of a guitar electronics book and take a gander at the schematic for anything made before 1960 and you'll see 250-500k pots and .02-.05uf tone caps. Take a look at the schematic for anything produced stock since 1990 and you'll see exactly the same thing. Why? Well, it works, but it's also the dead weight of precedent: it's what people have always used, and the parts are always available. Practical, but not inspiring. The informed reader will notew that the classic Strat schematic goes so far as to use the very SAME cap for both tone controls! TIP: The bypass capacitor that is suggested as a mod for your volume control, can also function as a bass-cut control. Remember, it provides a lower resistance path for high frequencies to go through than the volume control itself, when the volume is turned down a bit (which is why it appears to "preserve" the highs). WHICH frequencies it lets through more easily depends on the value of that capacitor. Higher value caps (i.e., greater than 1000pf) let through more of the upper midrange. A 1500pf bypass cap has the effect of letting through lots of midrange as you turn down the volume, resulting in a thinner sound; great for taking a rear humbucker and adapting it for "chicken- pickin" in a hurry, or keeping the bite but going a little easier on subsequent distortion stages. A smaller cap (<680pf) will tend to have a noticeable effect only if you have speakers with a decent high end, single-coil pickups, a clean sound, short cables, few stomp boxes without true bypass, etc. In short, it can't preserve what isn't being delivered in the first place, or conserved later down the signal chain. With respect to my earlier comments, if you have separate volume controls for front and rear pickups, you may want to install this mod on the rear pickup control but not the front one, just for flexibility and variety.

6/19/1997 6:33 PM

Mark Hammer

Actually expensive guitars DO include such
mods. I received an e-mail from John Suhr
(former luthier to Mark Knopfler, among
others, and currently employed by the Fender
Custom Shop) describing exzactly the circuit
depicted here (although I seem to recall it
was a 680pf cap and not 1000pf).

You'd be surprised at what expensive guitars
lack in the way of electronics, though. I've
harped on it before, and will harp on it again
here: front and rear pickups need *different*
tone controls, because you use the tone
control to do different things with them. So
far, so good. Do you think that a Les Paul
or even costlier instrument with front and
rear tone/volume circuits would install
different tone control wiring for front and
rear pickups, even though the cost difference
is absolutely negligible? Not on your life!

Volume and tone control circuits have
remained fairly stagnant for the last 45
years. Get hold of a guitar electronics book
and take a gander at the schematic for anything
made before 1960 and you'll see 250-500k pots
and .02-.05uf tone caps. Take a look at the
schematic for anything produced stock since
1990 and you'll see exactly the same thing.
Why? Well, it works, but it's also the dead
weight of precedent: it's what people have
always used, and the parts are always
available. Practical, but not inspiring.
The informed reader will notew that the
classic Strat schematic goes so far as to use
the very SAME cap for both tone controls!

TIP: The bypass capacitor that is suggested
as a mod for your volume control, can also
function as a bass-cut control. Remember,
it provides a lower resistance path for high
frequencies to go through than the volume
control itself, when the volume is turned
down a bit (which is why it appears to
"preserve" the highs). WHICH frequencies it
lets through more easily depends on the value
of that capacitor. Higher value caps (i.e.,
greater than 1000pf) let through more of the
upper midrange. A 1500pf bypass cap has the
effect of letting through lots of midrange
as you turn down the volume, resulting in a
thinner sound; great for taking a rear
humbucker and adapting it for "chicken-
pickin" in a hurry, or keeping the bite but
going a little easier on subsequent distortion
stages. A smaller cap (<680pf) will tend to
have a noticeable effect only if you have
speakers with a decent high end, single-coil
pickups, a clean sound, short cables, few
stomp boxes without true bypass, etc. In
short, it can't preserve what isn't being
delivered in the first place, or conserved
later down the signal chain.

With respect to my earlier comments, if you
have separate volume controls for front and
rear pickups, you may want to install this
mod on the rear pickup control but not the
front one, just for flexibility and variety.

6/21/1997 10:42 AM
Charles	>>You'd be surprised at what expensive guitars lack in the way of electronics, though.<< Agreed!! But ever consider that there were some guitars with real slick electronics that just didn't sell worth a danm? Think about the Les Paul Professional or the later Les Paul Recording. Then think about the L6S. Or even the ES335 with Varitone. There are others too, I'm sure you can think of some. Maybe the guitaris today is not really much more sophisticated than the player of years past. I dunno. I recently build an all HARD maple Tele. The neck has an ironwood fingerboad too. The pickups are an honest to god '58 PAF at the neck and a modern '57 Classic Plus at the bridge. It has a strings thru the body Strat non-trem bridge. I'm giving the description because there are both bright and warm elements to the instrument. I used the standard Tele control plate with only one volume and one tone. It was a real PITA to get the values of the caps, and especially the pots right. I ended up using a 350k volume and 500k tone (can't remember the tone caps, and bypass cap, but it took about a dozen tries to get it right). So.. I agree that there is a lot that the factories could do. Maybe they're afraid to change a sound that has become more or less classic. I haven't tried the TBX on a Strat but I hear it may be a step in the right direction as far as adding a little variety. Also... I'm making a small effect called the R&B Tone Ranger, which is a modern version of the passive notch filter offered in the Varitone. You may want to check out www.gate.net/~swampamp.

6/21/1997 10:42 AM

Charles

>>You'd be surprised at what expensive guitars
lack in the way of electronics, though.<<

Agreed!!

But ever consider that there were some guitars with real slick electronics that just didn't sell worth a danm? Think about the Les Paul Professional or the later Les Paul Recording. Then think about the L6S. Or even the ES335 with Varitone. There are others too, I'm sure you can think of some.

Maybe the guitaris today is not really much more sophisticated than the player of years past. I dunno.

I recently build an all HARD maple Tele. The neck has an ironwood fingerboad too. The pickups are an honest to god '58 PAF at the neck and a modern '57 Classic Plus at the bridge. It has a strings thru the body Strat non-trem bridge. I'm giving the description because there are both bright and warm elements to the instrument. I used the standard Tele control plate with only one volume and one tone. It was a real PITA to get the values of the caps, and especially the pots right.
I ended up using a 350k volume and 500k tone (can't remember the tone caps, and bypass cap, but it took about a dozen tries to get it right).

So.. I agree that there is a lot that the factories could do. Maybe they're afraid to change a sound that has become more or less classic.

I haven't tried the TBX on a Strat but I hear it may be a step in the right direction as far as adding a little variety.

Also... I'm making a small effect called the R&B Tone Ranger, which is a modern version of the passive notch filter offered in the Varitone. You may want to check out www.gate.net/~swampamp.

6/23/1997 9:15 PM
Mark Hammer	Complicated electronics DO tend to befuddle your average Smoke-On-The-Water-For-90-Minutes-Through- A-Fuzzbox-Until-The-Music-Store-Guy-Evicts-You musician. Older Schecters and BC Rich's had a certain cachet, but in the end I think people really didn't care about getting all the permutations and combinations. Sometimes, the electronics are also done wrong (e.g., the Gibson RD series). And sometimes, they're done right but are above the head of the people in marketing (e.g., the Les Paul Recording). My complaint was basically that a certain complacency had set in about guitar electronics, where guitars were wired in an almost automatic pilot fashion. Admittedly, things not broken should not be fixed, and it is difficult to install a stock circuit which is generic enough to work well with all conceivable replacement pickups while being innovative at the same time. Still, something as simple as having a front and rear tone control being optimized for the voicing characteristics of front and rear pickups (which ARE different; remember, that's why we have 'em) ought to be a fairly common affair, but it isn't. I want my bridge pickup to sound different from my neck pickup. I don't want it to turn into a neck pickup when the tone is turned down. As a popular beer ad showing on Canadian TV says "If I wanted water, I would've asked for water". Tone controls should turn pickups into something else, not just a muter version of the same thing. As for your notch filter, check out Craig Anderton's mid-notch filter in his projects book. It's much like you describe. He uses a centre-tapped transformer as his inductor, and exploits the tap to give several ranges.

6/23/1997 9:15 PM

Mark Hammer

Complicated electronics DO tend to befuddle your average Smoke-On-The-Water-For-90-Minutes-Through-
A-Fuzzbox-Until-The-Music-Store-Guy-Evicts-You musician. Older Schecters and BC Rich's had a certain cachet, but in the end I think people really didn't care about getting all the permutations and combinations. Sometimes, the electronics are also done wrong (e.g., the Gibson RD series). And sometimes, they're done right but are above the head of the people in marketing (e.g., the Les Paul Recording).

My complaint was basically that a certain complacency had set in about guitar electronics, where guitars were wired in an almost automatic pilot fashion. Admittedly, things not broken should not be fixed, and it is difficult to install a stock circuit which is generic enough to work well with all conceivable replacement pickups while being innovative at the same time. Still, something as simple as having a front and rear tone control being optimized for the voicing characteristics of front and rear pickups (which ARE different; remember, that's why we have 'em) ought to be a fairly common affair, but it isn't.

I want my bridge pickup to sound different from my neck pickup. I don't want it to turn into a neck pickup when the tone is turned down. As a popular beer ad showing on Canadian TV says "If I wanted water, I would've asked for water". Tone controls should turn pickups into something *else*, not just a muter version of the same thing.

As for your notch filter, check out Craig Anderton's mid-notch filter in his projects book. It's much like you describe. He uses a centre-tapped transformer as his inductor, and exploits the tap to give several ranges.

6/24/1997 4:42 PM
Charles	Mark, >>e.g., the Les Paul Recording<< Now there's one great sounding guitar that was too expensive and too ugly too be a decent product. Extra helping on UGLY. MY good friend Mike back in high school had one that he got used for about half price. It was a very interesting sounding guitar. >>permutations and combinations<< I've been saying that about guitars like the Jazzmaster and Jaguar. Too many buttons.. poor design to the layout, too much to remember. I can remember bass, treble, volume. Even the L6s (a later friend Angelo had one of those.. he was a Santana playalike) I didn't really like the rotary switch/pickup switching. I like pretty simple controls and think that the Varitone aka R&B Tone Ranger give me more character in the voicing. The ES335's with Varitone made sense to me. >>Craig Anderton's mid-notch filter in his projects book<< You're not the first person who said that. Some day I'll have to check it out. I got the idea from a schematic shown in an old "coffee table" book, just called "Guitars" (I think). I used different values than Gibson did, but the general idea is the same. I re-read your post. I figures Anderton would use a transformer for an inductor. Never do things the straight forward way... He might have had an old transfomer laying around... but I'd prefer to use a smaller, cheaper, lighter, more repetable, honest to God component inductor.

6/24/1997 4:42 PM

Charles

Mark,
>>e.g., the Les Paul Recording<< Now there's one great sounding guitar that was too expensive and too ugly too be a decent product. Extra helping on UGLY. MY good friend Mike back in high school had one that he got used for about half price. It was a very interesting sounding guitar.

>>permutations and combinations<< I've been saying that about guitars like the Jazzmaster and Jaguar. Too many buttons.. poor design to the layout, too much to remember. I can remember bass, treble, volume. Even the L6s (a later friend Angelo had one of those.. he was a Santana playalike) I didn't really like the rotary switch/pickup switching. I like pretty simple controls and think that the Varitone aka R&B Tone Ranger give me more character in the voicing. The ES335's with Varitone made sense to me.

>>Craig Anderton's mid-notch filter in his projects book<< You're not the first person who said that. Some day I'll have to check it out. I got the idea from a schematic shown in an old "coffee table" book, just called "Guitars" (I think). I used different values than Gibson did, but the general idea is the same.

I re-read your post. I figures Anderton would use a transformer for an inductor. Never do things the straight forward way... He might have had an old transfomer laying around... but I'd prefer to use a smaller, cheaper, lighter, more repetable, honest to God component inductor.

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