Rebuild of EB-J-JJ & EB-P-MM Twins
 

I'm embarking on a side project to rebuild two of my experimentation platforms and thought I'd share progress here and maybe pick up some ideas along the way.

I'll put in a few pics today and share more about plans in the days and weeks to come...

Here are a few pics...

Man you really love those mudbuckers! I totally dig the guard material especially that dark red pearl.

That pickguard material is the faux abalone that Axetreme Creations sells in several different colors. Have not used it before, but looks pretty cool to me too.

I do like the far neck pickup as a way to dial in some depth. At some point would like to try other pickup types in that position but the Mudbucker may be best for blending in some gut busting rumble.

Have considered the Dimarzio Model One and Willpower as well as the options from Curtis Novak. I have a hard time swallowing the Novak prices however on a pickup that, in my case, is used as seasoning rather than a primary engine like it is in a Gibson.

Novak has 3 options - a mudbucker, a more tame humbucker in mudbucker clothing and a pure single coil which is supposed to sound like a Dark Star.

I also want to try 3 alike pickiups, but probably not this time (like 3 big singles for example). The P bass could be made into a triple MM fairly easily though...and the J could be made into a JJ-JJ-JJ (triple quad coils would allow for something like 100 hum canceling wiring options).

The only pickup change I'm definitely making is to convert the bridge J pickup to a quad coil double J. I already have a second Area J bridge pickup. Planning to cut the ears off and glue the two together to make a double J and thicken up the bridge tone (when all 4 coils are in series).

Preliminary wiring plans...

J Bass:

- Series/Parallel/off toggle for each of 4 pickups
- Series/Parallel among the multiple J pickups
- Volume for each of the 4 pickups
- Master volume
- Master treble
- Master bass
- Preamp??
- Master kill
- Dual jacks (master+optional for mudbucker)

P Bass:

- On/off toggle for each of 3 pickups
- Volume for each of the 3 pickups
- Spin-a-split for the MM pickup
- Master volume
- Master treble
- Master bass
- Master kill
- Triple jacks (master+optional to split all 3)

Need to research best pot types and values to use in this way. The individual pickup volumes need to roll off gradually. I usually use 500k audio taper but they seem too sensitive.

Have considered putting one or two varitone type circuits on the treble horn (one for bass and one for treble) but am not sure if space will allow it.

The cap selector would determine frequency of tone adjustment and then the pot at the control panel would control the amount of rolloff at that frequency.

Also have drawings to do a similar concept in a stomp box but have not got to it yet - almost like a two band passive parametric equalizer. Cool concept onboard but in a stomp box probably more of a curiosity than a practical product.

Steve, your stuff is alot like what I do, the only real difference being where you and I elect to mount the ~stuffs~. You put the stuffs in the bass, I put the stuffs outside the bass in racks, stompboxes, and synth panels that are mounted in their own proprietary frames.

I love what you're doing with all of this.

** The "varitone" concept is an excellent notion, the different selections of voicing caps provide the various low pass filter knee-points (aka "cut off frequency" for us synth-heads).

** The pickup volumes essentially become a 3 or 4 channel mixer with the on/off switches being the "mute" buttons of each mixer channel.

I intend on doing a lot of the same things you have going on, but I lack some experience on some of the outcomes. Which is why I am experimenting with some of these ideas outboard. Once I figure out what I like/need, then I'll work up a layout and incorporate those innovations into a bass construct.

You have more experience of how certain design aspects will function as well as have some idea of what to predict will come from your efforts. Therefor you're far more willing to just jump in and do it up!

The one place I think you may have some issues is determining the pot values and curves that will work best to provide a good useable pickup mixing array. It's all to easy to fall back to old standards, even when those old standards are pretty crappy compromises at best. Hopefully you won't get discouraged along the way as you pursue the values and curves that will work best together and end up resorting to the old "250k" volume pots ... ~jest cuz~.

I've a question: When you say "mudbucker" is that just an endearment you use to describe ~any old humbucker~ or is that an actual trade name for a specific bass humbucker?

Recently I have located an Epiphone Thunderbird IV (a super nice specimen) which actually sounded really good to my very odd sense of hearing. So I am enthused about further pursuing the use of a humbucking pickup setup, at the very least in the F24 position. I have had some really poor experiences with humbucking bass pickups in the past (given my preferences in bass tones). So I'm interested in your choices in that arena. I know you prefer the 60s type bass tone (as oposed to my preference for the 70s rock bass sound). But even so, I am still very interested in adding some ~mud~ as a strengthening support, kinda like what you use it for.

Good on ya! These two projects look like a blast! I've subscribed to this project thread (you know how I luvs me some project threads!)

Keep on truckin'.

Fluxoid.

Hey Fluxinator, thanks for stoppin by! You are too kind in assuming I know more than I do!

Makes sense you would like the varitone thingy - it reminds me of something you have going. :-) One thing I have never seen is a dual varitone (parallel for treble cut and series for bass cut) which also has dual pots to control the amount of rolloff.

Mudbucker is a nickname widely given to the old Gibson EB style pickup. It's a specific type of humbucker. They have about 100 zillion miles of wire and can be used to pick up radio frequencies from nearby galaxies (seriously I get radio signals in my basement when the pu is removed from the shielded bass). The other attribute is a single set of polepieces between the two coils (thus they are oft called sidewinders). I'm told that the deep tone is due to a combination of both the location and the design.

Regarding the pots, I'm wondering if linear taper would have a more gradual rolloff and thus be better for the "trimmers" on the individual pickups. Seems like I read that somewhere. Audio tapers seem to roll off really fast. That can be good in some aps but not this one.

I'm hoping some other mad scientist will chime in and help me with some of these obscure points. :-)

With this thread I am indeed emulating the Fluxinator and your X rig and X bass.

I'm thinking linear taper pots will be better as controls for the individual pickups and audio taper for the master.

500k vs 250k, have to look into that more. I always use 500 or 1meg but there must be some advantage to 250.

Hard to say, the human audio reception array (ears, skull cavity, brain) doesn't always jive with math. I've had to work out many different curves and values to get blend systems to work to my satisfaction (and each time I'm working with different gain sources the requirements change). So while the math may say that using two linear pots will work best, the human audio array may have different ideas. If you look at how various values and curves interplay with one another on a chart/graph it looks easy-peasy. Then after you wire it all up it may sound like ass. Too quiet in the middle, or too loud in the middle (where the two curves intersect as one is going upward and the other is going downward). Comes down to some empirical testing and research (trial and error).

Look at how some amps use "audio curve" (aka Log) pots to obtain an even volume increase as the "Volume" knob is turned up. The sweep sounds linear but in fact the actual curve is logarithmic. It's just a fact of nature and science combining to create a perceived "correctness".

That's why I said I hope that you don't end up getting discouraged and just going with old standbys. I'd totally understand if you did though, it can be a maddening process.

:)

I want the rolloff on the individual pickup "trimmers" to be really gradual which is why I might try linear for the first time. We'll see. :-)

This project is going on the back burner for awhile...more later. :-)

...because at the moment I am distracted by this project...

My gawd you are a bold man. I barely have the gnards to get after routing into a $299 Squire! So what's goin' on with the Birthday Bass?

Seriously an M2500 geez!

It is scary. I'm inspired by David Schwab who put a bunch of extra pickups in a Ric. Also, a Warmoth body would cost almost as much as i put into this bass $500 on MF Stupid Deal of Day...and the spacing is perfect to add a third.

But for tone, its great as is.

Well, I cannot argue with solid logic! You're absolutely correct about the prices of using a Warmoth body (plus the rest), and you DID get a ~stupid great~ deal on the bass, that is for true.

So I suppose .... yea ... why not. What the hell, right? The worst thing that can happen is you won't like it and you can then remove the extra pickup and fab up a small cover for the hole and go on with life.

I mean, after all .... it's just a bass. Seriously, I mean it's not like it's some irreplacable object of art or preciousness. So .. sure .. do it up mangs!

:)

Shallow and fickle as it may sound, besides the tone experimentation, I just think 3 pickup basses look cool and am surprised there are not more of them.

In the end it is YOUR bass, if you want to make it look the way you want who is to say otherwise? I have to agree, a pile of magnet poles all smeared across the body is pretty macho looking! It looks ~mighty~ and capable, and as if there are many variations. You can sortof hear it in your head, whatever huge, powerful tone it is that one prefers seems to come out of the image of the instrument all by itself without even plugging it in.

Like people sometimes say about certain cars or motorcycles ... "it looks like it's haulin' ass even while standing still".

Yup. :)