Wiring up a new P/J set - Blend knob or two vol pots?

[bisonkills]

Right, I’ve finally pulled the trigger on a P/J (big) set from Wizard, to replace the stock pups in my Overwater Tanglewood Classic J. Already thinking ahead in terms of wiring them up.

Currently the bass is wired up with one volume pot, a blend pot and a tone control. Since I’m rewiring the whole thing I have a choice between a blend pot or two individual volume knobs for the P and the J. Is any one configuration better?

Let have your pros and cons…

[apa]

I was thinking the very same thing the other day since I have the urge for a new build. Im not a fan at all of the VVT but am of J's. I see you plumped for the Wizards. I am thinking of something a little more complicated in the way of an EMG active set. Only problem there is they come with all the active wiring and its VVT (If anyone knows of a fix to make it a stacked Vol/Blend and two tones Id be interested but back to the OT.

Its pretty straight forward if its a J set as far as volume is concerned but I think the P can over power the J in a PJ set making the mid point on a blend a bit imaterial. Unless you have discussed this with Andy at Wizard.

Ill be watching this with interest

[bisonkills]

If I'm totally honest, my blend pot usually ends up 80% P and 20% J. I almost thought of converting it to a P-Bass, but I figured I'd leave the P/J configuration for the added tonal options. It's nice to be able to dial in a bit more clarity sometimes.

[iiipopes]

It may be just what I'm used to, but after many basses over the 37+ years I've played electric bass, and having tried just about every configuration there is, active as well as passive, volume/blend, series/parallel, etc., I always go back to standard Jazz bass V-V-T for my basses. In a P/J configuration, what I do instead is 1) make sure the J bridge pickup is a hum cancelling pickup that blends with the P pickup, and 2) put a .01 inline capacitor between the hot lead of the J bridge pickup and its volume control to eliminate the "drop-out" when both pickups are full on.

[bisonkills]

[quote name='iiipopes' timestamp='1370371999' post='2099940']
It may be just what I'm used to, but after many basses over the 37+ years I've played electric bass, and having tried just about every configuration there is, active as well as passive, volume/blend, series/parallel, etc., I always go back to standard Jazz bass V-V-T for my basses. In a P/J configuration, what I do instead is 1) make sure the J bridge pickup is a hum cancelling pickup that blends with the P pickup, and 2) put a .01 inline capacitor between the hot lead of the J bridge pickup and its volume control to eliminate the "drop-out" when both pickups are full on.
[/quote]

Hey iiipopes, interesting and helpful reply. Can you clarify how the cap eliminates the drop out? Does this somehow help the discrepancy in P (big output) vs. J (lower output)?

Can you link to a wiring diagram that illustrates this in practice?

[iiipopes]

When both pickups are full on, the impedance is roughly half of either pickup alone. This is compounded by what is known as "comb filtering," where the fundamental or a significant overtone may be out of phase with itself from pickup to pickup because of the inherent nature of the way a string vibrates in segments as well as the whole. These two aspects together cause a slight signal decrease when both pickups are full on compared to, say, full on with the P pickup and 8/10 on the J bridge pickup. The .01 inline capacitor acts as a high-pass filter, filtering out the lows and making the circuit more reactive so it addresses both these issues. You don't really notice it when the J bridge pickup is full on by itself, because that close to the bridge, there is little string excursion over the polepieces compared to the P pickup, especially if the pickup is in the "70's" closer position to the bridge (which works better with a P pickup to get more highs than the slightly farther out "60's" position of the J bridge pickup). This accounts for the lesser output and less fundamental that comes out of a bridge pickup anyway; it's why the bridge pickup sounds like it does. I also change out the .047 tone cap for a .033 to retain more mids when I turn down the tone, which also keeps the overall signal up the slightest bit. I came up with this myself. If I have time, I'll draw it, pdf it and post it.

Edited June 5, 2013 by iiipopes

[threedaymonk]

[quote name='iiipopes' timestamp='1370440088' post='2100869']
The .01 inline capacitor acts as a high-pass filter […] I also change out the .047 tone cap for a .033 to retain more mids when I turn down the tone
[/quote]

It's probably obvious to people who only or frequently use capacitors in guitar wiring, but it would be helpful to specify the units of those capacitances! I assume µF as 0.01µF should give a cutoff frequency of around 800Hz for a 4H pickup, which sounds about the right order of magnitude. Is that correct?

[iiipopes]

Yes. Sorry about the omission. In the USA, µF is the understood unit unless otherwise stated. Thanks.