Help!! Please Dimarzio Model J Question

[fhm555]

Hey folks. I've got a set of Model J's in a little MIM J and was thinking about trying some different wiring.

Here's the Dimarzio diagram I'm wanting to copy. Anyone tried it, and what did you think? Still using it or not? And last, what value/type pots, caps, etc should I be looking to use?

Thanks in advance for any and all input, opinions, and experiences.

 

[RobbieK]

The dual sound thing with dimarzio dates back at least to the early 80's, possibly even the 70's. The switches are simply series/parallel switches. If you like the fat mid-rangey tone of these pickups as they are (in series) you may be unimpressed with their tone in parallel. It is brighter and quite a bit softer. Around 6dB. I've never been a huge fan of series-parallel switching unless it's in conjunction with an onboard preamp either to boost the parallel sound or to buffer the series sound (or both). Definitely go for it, but don't expect miracles.

Asking which pots to use for a passive bass circuit around here can turn into a pretty big deal. I'd use 250KA pots for vol tone, and blend. Notice the top left and bottom right lugs of the blend pot are wired together, then soldered to earth. I'd recommend leaving this til last. Solder a wire to each of these lugs, and listen to the bass with these both connected and not connected to earth.

 

[line6man]

That will only work with an A/C taper blend, and even then, it's a compromise. I would opt for an ungrounded M/N taper blend, with summing resistors to give the tone control isolation.

 

[RobbieK]

That will only work with an A/C taper blend

Nah, the circuit you've posted will work fine! When your blend is in the middle, either tone pot works as a master tone and rolls off treble from both pickups. But in practise this doesn't really matter to the majority players. It's been discussed many times here, if you really need two tone controls that work more or less independantly in a passive bass, then an A/C blend pot is ideal (I usually leave these unearthed in passive circuits), but they are very expensive. As line6 said though, if you add a couple of 22K resistors (a few cents from an electronics store), you get pretty much the same effect with only a very slight drop in volume when either pickup is solo'd. People make far too much of this volume drop. You'll barely notice it. But for that matter, people make far too much of non-interactive tone controls. If those four controls are the one's you need, this circuit will be fine.

FYI, in a passive bass, either of these blending setups will roll a tiny bit of treble off. Plus the addition of an extra pot will also roll just a tiny bit of treble off even with the tone pot all the way up.

 

[fhm555]

Thanks for the info folks.

I'm just looking for something that will fill 4 holes in a J control plate. I've got a Deluxe that came to me with a fried pre and after 2 disappointing attempts at replacing it I've decided to just run it with the Model J's and some kind of passive set up.

Since the Deluxe has a side jack I've got 4 holes in the control plate to fill and I was basically looking for that when I found this diagram. I'm by no means married to this set up so if you have something more practical or useful, so long as it fills 4 holes in a control plate, I'd be most interested in taking a look at it.

I mostly play blues, country, and guitar driven r&r

 

[MIMike]

You could put a jack on the control plate and bypass or remove the side jack. I've never been a fan of the side jacks.

 

[fhm555]

You could put a jack on the control plate and bypass or remove the side jack. I've never been a fan of the side jacks.

Thanks for the opinion but I'd rather not have any open holes or non functional covers. I've got a few standard J basses and was hoping to take advantage of this situation to play around with control setups not available to me in a standard jazz.

I've got an active J Plus with an excellent (kubicki) preamp that is at once simple to use and great sounding. Because of the great performance from the Plus I've always wanted to try an active standard J. To that end I've tried a couple other preamp's in this Deluxe, but none of them have really blown my dress up so I've decided to quit laying out $150~$250 on any more preamps without being able to try it before I lay out the money.