Help! Wiring experts: options for ES-339

GDSmithTX

GDSmithTX

Corporate cog
So I've got a set of Guitarforce Lord of the Blues pickups on their way to replace the okay-but-not-excellent stock pickups in my cherry Epi 339 Pro. Since the tech has to pull the whole wiring harness for the pup upgrade anyway, I might as well have have him replace it with good quality components while he's at it.

I'm going to want 50s style wiring and to get rid of the push-pull split option, because it's not that useful to me.

But one of the things I'd like to do is use some sort of variation of the very nice G&L PTB (Passive Treble Bass) controls on my G&L Legacy Tribute. Here's a link to a dual humbucker adaptation of it, but it's for a 3-knob guitar. I need something for a 4-knob guitar like the 339.

Any suggestions / diagrams / etc? The wiring will be done for me by a pro at Heights Guitar Shop here in H Town.
 
Your tech should be able to wire up individual vol pots that share the one set of tone controls.

That's an interesting setup; I may try it on my les paul.

I found that changing a coupling cap in my picovalve to remove lows made the amp clearer. I think you'll have to be careful with the value of the cap on the bass control - maybe try some different values.
 
wagdog said:
Your tech should be able to wire up individual vol pots that share the one set of tone controls.

That's an interesting setup; I may try it on my les paul.

I found that changing a coupling cap in my picovalve to remove lows made the amp clearer. I think you'll have to be careful with the value of the cap on the bass control - maybe try some different values.
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I thought the idea was to have individual tone controls to control each aspect? Why would you want the volume controls to share a tone control?
 
gtrjunior said:
I thought the idea was to have individual tone controls to control each aspect? Why would you want the volume controls to share a tone control?
Click to expand...
I would wire it so there were individual vol pots and they would share the tone controls (one for bass cut and one for treble).

If you wanted each pickup to have their own vol and set of bass cut/treble tones you would need 6 pots. If that's desired, I would look into concentric pots for the tone pots.
 
wagdog said:
I would wire it so there were individual vol pots and they would share the tone controls (one for bass cut and one for treble).

If you wanted each pickup to have their own vol and set of bass cut/treble tones you would need 6 pots. If that's desired, I would look into concentric pots for the tone pots.
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Gotcha....sorry, I misunderstood you're op.
 
gtrjunior said:
I found this: it talks about doing this mod with both 3 and 4 knob guitars

https://www.premierguitar.com/articles/21112-three-must-try-guitar-wiring-mods
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That looks to be just the thing, and it's by Joe Gore, the same guy who wrote the article I linked to. Thanks!

Here's the diagram in case anyone is interested in it:

Diagram1c_WEB.jpg
 
I watched the video you posted and it seems like a really useful mod. The guy in the video had a horrendous tone with the distortion though.
 
gtrjunior said:
I watched the video you posted and it seems like a really useful mod. The guy in the video had a horrendous tone with the distortion though.
Click to expand...

I think he's doing it deliberately, demonstrating various configurations of the knobs to let you hear the effects of the mod. I know with my G&L Legacy's PTB really helps the tone "clear up" under heavy distortion or fuzz and if I turn it the wrong way it sounds like ass.
 
Kind of a near demo vid. I kind of think it sounds sort of like a variatone circuit, but with the 'infinite' adjustability of a knob. I think it makes for some cool sounds and I'm eager to hear how it works out for you.
 
Question: In the diagram above, does the voltage of the tone caps (all paper in oil) matter? 600v, 630v, 400v ... does it make a difference?
 
GDSmithTX said:
Question: In the diagram above, does the voltage of the tone caps (all paper in oil) matter? 600v, 630v, 400v ... does it make a difference?
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Voltage in a tone cap makes no difference at all. Maybe Eric Johnson has something different to say, but in my opinion it means nothing. There is no significant voltage going through them in a guitar circuit. The capacitor in these circuits is used primarily for the frequency filtering function and not the electrolytic storage of charge.
 
I was thinking, NO, capacitance is meausered in farads or micro farads. Higher voltage rating just makes it more bomb proof. Then I read this:

-1down vote
Yes, the voltage is the high end rating of the capacitor but the capacitor is for storing electrons measured in farads or microfarads.

If you forget about the technical jargon, think of it like a battery. Not quite the same but if you have a 24 volt battery supplying a circuit that has a cut off of 19 volts and you only charge it to 12 volts, you have a lot less electrons to supply your circuit than what is needed and chances are the circuit won't work.

A 25 μ'>μμ F capacitor that is rated at 16 volts will have a 25 μ'>μμ F capacitance when operated near the 16 volts but if you substitute a 25 μ'>μμ F capacitor rated at 35 volts you will not have 25 μ'>μμ F capacitance if you only apply 16 volts.

These capacitors have many functions in circuits. One main function is to supply electrons to a circuit when the normal plug in supply has dropped lower than needed such as with alternating current. As the voltage and current reverse, 60 times a second, the level goes from around 170 volts peak down to zero volts and on down to -170 volts and then it repeats. The capacitors filter this drop by supplying the appropriate voltage to keep the circuit smooth. As the voltage rises back up again, it recharges the capacitor.

A leaky capacitor has the effect of a large rated capacitor that leaks and keeps the circuit from working properly. In most cases, you can over rate a capacitor and get away with it. If you double the voltage value of the capacitor but keep the supply voltage low you might want to also double the Farad value. Ex: 25 μ'>μμ F at 16 volts to become 50 μ'>μμ F at 35 volts running on 16 volt supply.
 
Bob411 said:
I was thinking, NO, capacitance is meausered in farads or micro farads. Higher voltage rating just makes it more bomb proof. Then I read this:

-1down vote
Yes, the voltage is the high end rating of the capacitor but the capacitor is for storing electrons measured in farads or microfarads.

If you forget about the technical jargon, think of it like a battery. Not quite the same but if you have a 24 volt battery supplying a circuit that has a cut off of 19 volts and you only charge it to 12 volts, you have a lot less electrons to supply your circuit than what is needed and chances are the circuit won't work.

A 25 μ'>μμ F capacitor that is rated at 16 volts will have a 25 μ'>μμ F capacitance when operated near the 16 volts but if you substitute a 25 μ'>μμ F capacitor rated at 35 volts you will not have 25 μ'>μμ F capacitance if you only apply 16 volts.

These capacitors have many functions in circuits. One main function is to supply electrons to a circuit when the normal plug in supply has dropped lower than needed such as with alternating current. As the voltage and current reverse, 60 times a second, the level goes from around 170 volts peak down to zero volts and on down to -170 volts and then it repeats. The capacitors filter this drop by supplying the appropriate voltage to keep the circuit smooth. As the voltage rises back up again, it recharges the capacitor.

A leaky capacitor has the effect of a large rated capacitor that leaks and keeps the circuit from working properly. In most cases, you can over rate a capacitor and get away with it. If you double the voltage value of the capacitor but keep the supply voltage low you might want to also double the Farad value. Ex: 25 μ'>μμ F at 16 volts to become 50 μ'>μμ F at 35 volts running on 16 volt supply.
Click to expand...

Ummmm, thanks.

giphy.gif


Is that still a no?
 
That's a, I thought I knew what I was talking about but, apparently I don't so, I'm going to defer to somebody smarter.

What I thought was THE ONLY difference is, it having the capability to not blow up in a high voltage circuit. Like, can I carry 5 gallons of water in a 10 gallon bucket? Well duh, yes.

What I get from this is, it does matter. How much of a difference, can you hear it? I don't know.
 
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Voltage for a tone cap in a passive guitar circuit does not matter. The voltage swing is in the millivolts. I believe some high output humbuckers can put out over 1v. Still, I've yet to come across a cap rated less than 25v, and those were electrolytic.
 
Next question: any problem using 500K audio taper pots for both tone and volume? Or should the volume be audio taper and the tone linear taper?
 
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