Capacitors/help

[willeevee]

I'm replacing the PUPS (p/j) on a Peavey DynaBass Unity Series with Dimarzios, plus adding a Will Power neck pickup. I'm wiring all three to stacked tone/vol pots - all passive.
My question is: what type & how many capacitors do I need?
Thanks!

 

[Lo-E]

If you're using three p'ups and each will have it's own tone control, you need three caps. The cap value is a matter of taste, but anywhere in the .02 - .05 microFarad range will work for you. Don't get too caught up in the type of cap. Polyester film caps, ceramic caps or mica caps will all work just fine in this application.

 

[line6man]

Having three tone controls is not a good idea, as they will interact.

Generally, however, one capacitor per tone control, of any voltage handling capability and any composition, as long as it's non-polarized.

 

[willeevee]

I read about that "tone interaction" in another thread. One reply recommended using "resistors" to eliminate that but, there would be some loss of gain.

 

[line6man]

I read about that "tone interaction" in another thread. One reply recommended using "resistors" to eliminate that but, there would be some loss of gain.

Loss of output, not gain, but yes.

 

[Lo-E]

You can put resistor networks across the volume pots and the loss of gain will be negligable. Do a google search on "bleeder resistors" for more info on this trick.

 

[willeevee]

Thanks very much

 

[willeevee]

Any recommendations for the value of each cap for each pup?

 

[Lo-E]

Fender typically used .05mF. You can use that as a starting point.

 

[line6man]

You can put resistor networks across the volume pots and the loss of gain will be negligable. Do a google search on "bleeder resistors" for more info on this trick.

No, that's something else. The treble bleed mod will not help here, because the resistance is parallel to the pot, but it needs to be in series with the signal path.

And once again, this is not a question of gain, it is a question of output.

As far as capacitance goes, the standard value for high impedance signals is 0.047uF. Everyone has their preference, however.

 

[Lo-E]

IME, adding treble bleed resistor networks has also helped to reduce interaction between controls in passive basses.

 

[line6man]

IME, adding treble bleed resistor networks has also helped to reduce interaction between controls in passive basses.

No, it would actually make the problem worse. When the volumes are up, the resistors are shorted, and the pickups are parallel with no resistance between them. Rolling down the volumes increases the resistance between pickups. With the resistors there, you decrease the total resistance through the pot, because parallel resistances decrease in total resistance.

 

[Lo-E]

No, it would actually make the problem worse.

On paper, perhaps. In fact, on paper, definitely!

I didn't do this mod on paper, however. I did it to my bass with a soldering iron. Whether or not it defied logic, it worked. The controls were considerably less interactive after the mod.

 

[willeevee]

Well I'm gonna research (google) it & talk it over with the guy doing the work.
I'm absolutely positive that I want individual tone controls for each pup, so we'll see.
Thanks for all the input.

 

[line6man]

Well I'm gonna research (google) it & talk it over with the guy doing the work.
I'm absolutely positive that I want individual tone controls for each pup, so we'll see.
Thanks for all the input.

So then put a resistor in series with each output, summing to the jack, or preamp input.

220k is the traditional value for Jazz basses.

 

[SGD Lutherie]

IME, adding treble bleed resistor networks has also helped to reduce interaction between controls in passive basses.

The treble bleed circuit stops you from looking high end when you turn the volume control down. That's all it does.

It will not stop two tone controls from interacting.

 

[FunkMetalBass]

The treble bleed circuit stops you from looking high end when you turn the volume control down. That's all it does.

It will not stop two tone controls from interacting.

I used to think it was bad when people judged me for "not looking high end" when I played a Squier instead of a Fender. Now they're going to judge me for having a few extra resistors in my bass?!

When will it end?!