Alternative J-bass Wiring
I am of the notion that a j-bass is one of the most versatile basses on the market in that it's tone is suitable for many genres of music. However I feel it lacks the full and solid punch of a p-bass and obviously Fender® felt the same way and came up with their S-1 switching concept which changes the two jazz pickups from being wired in parallel to series. It's amazing just how effective this simple little wiring mod can be. To add even further tone shaping capabilities I (at one time) incorporated a version of Fender's® TBX system... a treble/bass cut tone pot. In the middle position the pot allows the signal to pass unaffected. Turn the knob clockwise and you begin cutting bass... turn counter clock-wise and you begin cutting the treble. Wiring Schematics:
- Dual single coil j-bass S-1/TBX wiring (2 vol, 1 tone)
- Dual single coil j-bass wiring with master volume (3 vol, no tone)
- Simple dual single coil j-bass parallel/series switching (2 vol, 1 tone)
- dual parallel/series switching with "out of phase" DiMarzio Model One humbucker (3 vol, 0 tone).
- dual parallel/series switching with "in phase" DiMarzio Model One humbucker (3 vol, 0 tone).
- dual parallel/series switching with "in phase" DiMarzio Model One humbucker (2 vol, 1 tone).
There is one major difference between schematics #1 and #2 in that with the simple S-1 switch, the bridge volume pot is deactivated during series mode and the neck pickup handles the volume for both pickups which are essentially handled as one large humbucker. In the S-1/TBX wiring the bridge volume pot becomes the "master" when in series mode. Check out both schematics and combine them if you wish to come up with your own custom wiring. For schematic #3 I've added a volume pot with a series parallel switch for a Model One® humbucker. Usually the volume increases when switching from parallel to series so to address that issue and at the same time thin the thick muddy sound the "series" mode puts the pickup out of phase with itself (remember, it's basically two siamesed single coil pickups). Schematic #4 is like #3 but it leaves the Model One® in phase with itself.
Here a few sound samples which were played over the bridge pickup, a clean tone pot and D'Addario Chromes flatwound strings (ECB-84 40-100). I just plugged the bass directly to the PC via a sound card. Recording quality isn't the greatest since my soundcard is rather crappy (highly technical computer jargon) but it's all I can offer at this time.
Additional Wiring Tips - using a capacitor and resistor in parallel
- Treble Retention Wiring - by connecting a 680-1000 pf (picofarad... not microfarad) cap and 150K resistor in parallel across the two active pins of a volume pot, highs are no longer cut by the pot when lowering the volume.
- Anti-shock Circuit - Another recommended use for a cap (.001uf, 500 volt minimum rating) and resistor (220K ohm) in parallel is an "anti-shock" circuit wired between the control plate ground and the string or bridge ground. It prevents electrocution due to a mismatched ground between a guitar amp and a PA system.
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