Different ways to configure a PJ....

[fig]

Some other minor advantages I see with the single layer (standard) pot blend thing are:
-Standard pots generally less expensive than double layer blend pots.
-Probably (not sure) a larger variety, and easier sourcing, for unusual pot resistance values.than double layer blend offerings.
-Once the switch is in place and wired up, a bad pot just has 3 solder spots (terminals) for replacement. Double layer blend has 6.
-Standard pot uses less vertical space in control cavity.

Edit: I looked back thru old posts, I think I was working with TB member degailen97 when he came up with this. It was derived from a circuit by Bill Lawrence we were working on. Credit to degailen97 and Mr. Lawrence.

 

[bdplaid]

No, there’s still the same master volume pot and tone as VBT. A blend pot has one pickup full and the other lowered at some proportional resistance based on which side of center the pot is set. Here, the switch chooses which pickup to lower instead of the half of the blend doing that.

I read it as just using a single pot as volume for both pickups. My mistake.

For me it doesn't beat VVT. A passive blend pot just knocks off too much high-end for my tastes, and running it ungrounded means the pickups never totally are soloed, another thing I don't like.

I've had loads of variations of passive wire-ups. I finally realized that the best and most versatile are the traditional VT for P Bass, and VVT for Jazz bass. One has to learn how to use them, though. backing off the volume a little and playing with the tone changes things, because they interact. Even treble bleed fell by the wayside for me because of the pot interaction factor.

It's a lot of fun and educating to experiment, though.

 

[bdplaid]

Some other minor advantages I see with the single layer (standard) pot blend thing are:
-Standard pots generally less expensive than double layer blend pots.
-Probably (not sure) a larger variety, and easier sourcing, for unusual pot resistance values.than double layer blend offerings.
-Once the switch is in place and wired up, a bad pot just has 3 solder spots (terminals) for replacement. Double layer blend has 6.
-Standard pot uses less vertical space in control cavity.

Edit: I looked back thru old posts, I think I was working with TB member degailen97 when he came up with this. It was derived from a circuit by Bill Lawrence we were working on. Credit to degailen97 and Mr. Lawrence.

Don't forget, you need to source a proper MN pot, not just any blend pot.

 

[J Wilson]

My two cents:

I prefer either:

Volume, tone, 3-way selector, or . . .

Volume, balance, tone, since . . .

. . . . volume, volume tone drives me nuts, as once I get the tone I want on the blend of the two volumes, I can't turn the bass up without losing that tone. I played active basses for years, and I had my Jazz Bass 'converted' as soon as I could, hated two volumes. There's those who think the pan pot somehow loses something or changes the tone, and I could care less as it works for me just fine.

As far as the PJ combination:

Do yourself a favor and buy a matched set from whatever pickup builder you're considering. Otherwise it's real easy to wind up with a setup where you just can't get the J pickup as loud as the P pickup. I'd also prefer a humbucking J (either a stack or side by side coil setup) as you skip the single coil noise, and usually the output is far easier to match to the humbucking P pickup.

 

[JKos]

Since blending has been mentioned alot in this thread, here's a blend that uses a regular pot for blending.

That’s nifty. I like it except it does still have an extra load at all times. For example, if you use a 250k pot for the blend and a 250k pot for the volume, that’s a 125k load on the pickups which is a bit much (usually).

If one were to change the blend pot to, say, a 10k pot, cut the trace or cover the trace at the “ground” end and not ground it, that would be dope and implement electrically just what I mentioned previously.

If you wonder why I keep mentioning 10k, that’s because I found that to be about the limit for a useful blend. In other words, putting more than 10k in series with the pickup being blended in is about like it not being there at all.

 

[fig]

I like it except it does still have an extra load at all times.

Fortunately the ungrounded or trace-cut mods can be used for the single pot blend, since the single and dual layer blends are the exact same circuit. Only thing different is the actuation method (rotate or switch) to make one pickup adjustable at a time.

A new idea, and in my opinion, an improvement, over the dual layer method. For players that don't like the half-rotation sweep of the dual layer blend pot, this idea is one to consider.

FWIW I don't care for blends. Prefer two volume pots. Ironically, the new bass I bought over a week ago has a two layer blend pot LOL. Acceptable, 'cause everything else about the bass suited me. When my 45 day trial period is up, I'll probably be changing some things (cavity space permitting).

 

[fig]

Correction to a previous correction: The single layer blend idea wasn't degailen97 or derived from a Bill Lawrence circuit.

Was entirely TB member jesterbass.

Just found my error. Apologies all around.

 

[stevensivak]

Amazing- it's like the variables just keep coming!

Does anyone have a source for the 10kohm M/N 6 lug (dual layer) pot? I can't seem to find one...

 

[SharpCat]

Search for MN10K on the big A. IMHO, 10K is going to be too low. YMMV.

 

[Kevin Wolfe]

I’m not using an MN pot and it works good enough. I never really adjust the blend once I fin the setting I want. I never use just the bridge pickup either.

 

[stevensivak]

Could not find the tens, so I ordered the 100s which are available through Mauser

 

[ThudThudThud]

I built a JJ bass on a Precision body platform with VVT, with the first V being a push-pull pot for series/parallel. Added a new dimension.

 

[SharpCat]

Finally wired a bass with the single pot blend circuit @fig posted in post #55. Wired it with 500k master volume (linear), 500k linear push-push pot/switch for blend, and 250k/0.033uF cap audio tone pot. No no-load or no-ground wiring changes from the schematic. The schematic doesn't specify pot values as far as I could see. My thought was that the impedance presented to the pickups is the parallel of the 2 500K pots, so 250K.

Relentless PJ pickups on this bass, previously using the 500K VVT circuit DiMarzio recommends.

Initial thoughts:
1. Seems to mostly work well.
2. Noisy when the master volume isn't at 100% or 0%. Turning the volume down even a slight bit brings out noise.
3. The ability to flip/flop the balance between pickups with a single tap is nice.

My main surprise was how much in usage this feels like a VVT control layout rather than a VBT one. People not happy with VBT might like this layout more. For my part, I think I'll go to VBT soon--I don't like VVT much.

 

[fig]

Finally wired a bass with the single pot blend circuit...

Cool you wired it up and chimed in about it. Rather sucks about the noise, though. That circuit came from another player in here I was working with, so I drew it up for myself. You're right, for folk that may not like a regular half rotation blend pot, this is a fine alternative.

I leave component values out 'cause I've noticed that a circuit that works on one bass sometimes doesn't operate and/or sound the same on another. So I leave it to the player-installer to sort out functionality and operational/sound preferences that suits them best.