Okay, so, I've got an old Stagg XB300 four-string bass kickin' around. It's noisy as hell and the pickups are less than stellar, but I'm just too fond of it to toss.
So I figure I'll rewire it.
Problem being, the more I try to research how to do such a thing, the more confused I get.
The bass has a neck single and a bridge humbucker. Controls are a volume pot, 3-way selector switch, and a tone pot.
Ideally, I'd like to replace the pickups and refit the electronics - a new volume pot, a blend pot instead of the selector switch, and a concentric tone pot, one for each pickup.
I know how to solder and mount and whatnot, and I think I understand - in theory - what does what, but the wiring is confusing me. If anybody out there's good with markers and pots, I'd really appreciate it if someone could sketch up a quick and dirty diagram to get me going on the right track.
So I have my neck SC and my bridge Humbucker, each running through their own cutoff switch, volume pot and tone pot, then merging into a blend pot. Also bridge and pickguard ground lines - I intend to build myself a metal pickguard.
Each pickup's volume and tone will actually be the tip/base of a concentric pot, respectively.
I know, by the way, that the cutoff switches are totally pointless, especially when I have both individual volumes AND a blend. But I like switches and things, and they won't hurt - right?
Also, I'm seriously considering ordering a Black Ice passive overdrive from StewMac, and slotting it in on the neck circuit.
But anyway, have I made any huge glaring errors that could cause the thing to blow up in my face?
I'm going to be out shopping for parts in a couple of days, so if this little plot of mine is going to short-circuit my expensive new pickups, please tell me now!
So far, you've been doing a bang-up job, carrying on a complete discussion all by yourself! But I thought it's time to let you know that you aren't operating in a complete vacuum here, so.....
Your diagram will work as posted. However, be aware that we have discussed the concept of pickup blending a lot, recently. You be doing yourself a favor if you were to search the forums (link in the menu bar above), and look for 'blend pot'. Go back for at least 180 days, and ask for 20 results. Should make for some interesting reading.
When your head clears from all that, we'll be here to answer your (inevitable) questions. ;D
Rule #1: All Lives Are Final. Make sure that the life you have just been issued is appropriate for your needs, before departing the womb.
Rule #2: In case you don't like the life you have, see Rule #1.
Thankee kindly, sir (or madam) - I was a lonely child, what can I say? I realized about a minute after posting the first message that asking people to do my dirty work for me was not entirely polite, though, so I redoubled my efforts, and here I am!
...I'll look into the blending threads in more depth, however, for the nonce I am satisfied with 'It'll work'.
However, ought I place the tone pots ahead (in the circuits) of the volume pots? Does it matter?
I've also decided to add a master volume (can't believe I forgot it) after the blend pot, and a master cutoff between the master vol and the jack... this switch, like the others, mostly just for looks and fun.
However, I've also been reading up on the Black Ice Overdrive. According to the folks at Harmony Central, it works fine with basses (provided the pickups push enough power), and so I've been seriously considering adding a Black Ice to one or both pickups' tone pot - switchable, of course, via a ON/ON switch from clean tone to overdrive. A diagram will follow later tonight, but what say as to the concept?
Along those lines, apparently two Schotty diodes are exactly what a Black Ice is. Has anybody had any experience with similar tweaks?
And this, lastly, is a subject for another thread - but I'm seriously considering modding my Fender FV-1 electric violin as well.
Ah, excellent, many thanks! I will check it out right away.
But in the meantime, here's the quick-and-dirty circuit sketch of the bass project, fitted with the master volume, master cutoff, and tone pots rigged to switch from 'Tone' to 'Overdrive', either via a Black Ice box or diodes.
Quick and dirty, like I said - I hope no large errors slipped under my QC.
Oh, and another question for you folks - is my love of switches going to have a negative effect on my sound?
...so I've just examined my violin, and upon re-evaluation of the task at hand, I've decided to drop the whole subject of diode-based distortion until further notice. I will not build it into the violin, and I'm just gonna bite the bullet and get Black Ice cubes for the bass.
Having been reminded intimately of how particularly delicate a violin is - even an electric one - I'm going to stick with the basic plan, which is to simply install a professional-grade piezo pickup and a 3-way selector switch. This happens to be my first mod, and I will let you folks know how it goes - provided, of course, that I can find a switch that suits me. I plan to begin (and end!) on Thursday night.
I've built and mounted the pickguard on the bass. It's made from 22-gauge steel sheet, coated against corrosion on the back side, brushed on the front (and left to discolor natuarally), and is screwed down solidly and grounded, covering the hole where the neck pickup used to be.
I have, speaking of which, removed said neck pickup, opting instead for only a bridge pickup, as I never actually used the neck unit. The bridge pickup is still the stock humbucker, but I'm currently shopping around for either a very hot bass humbucker, or two single-coils to replace it with.
I have also shielded and grounded the body cavities with aluminium tape, and the incredible improvement in sound this provides has pretty much nullified the need to replace the pickup at all. I'm going to anyway, though. Eventually. Other changes on the menu are tuners, bridge, pots and jack (when I change the pickup), and a truss rod cover will also be made from steel, when the tuners are replaced.
As for the violin, I have added the professional-grade pickup, which happens to be so professional that it is completely unusable, grabbing dynamics so broad that they're painful, and even picking up the sound of the bow across the strings! I'm sure that as I mess around with the amp and other equipment, I'll find a way to utilize its stunning gain, though.
Each (piezo) pickup is also running through its own on/off cutoff switch, allowing me to use either, both, or neither with the flick of a finger.
All this was accomplished in the past few days, despite a couple of minor setbacks (my soldering iron exploding, for example), and I am quite impressed. I'll see what I can do about posting images.
...oh, and I should add that removing the neck pickup has turned the bass's 3-way selector switch into essentially a cutoff/mute switch. I had intended to mount these pretty much for decoration, however, having a cutoff switch on the unit has convinced me of the idea's utility, and on any further mods I perform on any other instruments I obtain, you may be sure that I will mount a cutoff switch on every pickup, in lieu of a main selector.
I will mount a cutoff switch on every pickup, in lieu of a main selector.
The objection to so doing is that you have a dead position if all the switches are set to "off". Not desirable if you are into flailing around onstage.
having a cutoff switch on the unit has convinced me of the idea's utility
I have a hollow-body with a "standby" switch, that is, a master on/off, which is nice 'cause it allows one to leave the guitar plugged, amp on, while on stage, for taking a break. But it's well out of the way of the other controls so it doesn't get inadvertently actuated (or de-actuated)- see reason #1 above.
But apart from that limited usefulness, I'm not a big fan. Probably more useful if using a tube amp where warmup is an issue, with SS you can always just turn the amp off.
Hmm... suppose I could just use a master cutoff, or 'standby' as you put it - which is what'll probably end up happening, as I only intend to mount one top-grade pickup on the instrument. Should I choose to use two, though, then I'll certainly mount a cutoff for each.
Definitely a worthwhile point to mention, the flaily-bit - while I do tend to move around while playing, and likely will move even more when Black Avalanche takes the stage, I don't see it as being a problem, especially if I use very small switches and locate them cleverly - like, say, between the pots.
The big draw of the plot, you see, is that I'm pulling lead vocals as well as lead (read: solo) bass. Which means that most of the time, the bass will be under my arm while I bounce around the stage, snarling at the audience. Being able to mute the instrument without messing with pots will be a feature highly desireable, I don't doubt.
Having gotten sick and tired of it halfway through, I ended up with a single bridge humbucker running through a volume and tone pot. There's a new steel pickguard and accent plate, body cavities are fully shielded, a strat-style jack plate has been mounted, and all electronics have been completely replaced, right down to the tone cap.
If I ever find my camera, I'll post pictures.
You may have noticed the end result is much less grandiose than I predicted - this is because I've simply decided to purchase a new bass down the road, rather than pump all the money and effort into this one. I wanted an ESP F-404, but, to my dismay, they appear to be out of production.
I've fitted a new Hipshot A-style bridge, replaced the stock powerbucker with twin EMG HZ-40's wired up as a single quad-rail double-bucker, fitted a new bone nut (jeez that stuff smells awful!) and took then neck in by 7/8's to make it all work.
Now, however, I am still not satisfied. Now I want to redo the controls to be three switches and no pots, controlling volume, volume, and tone. I figure three DPDT on-on switches, each running into the next, each of which throws a resistor (for the vol switches) or a resistor and a cap (for the tone switch) into the line, or bypasses it as the case may be.
I'm working on the schematics, but my question is - why haven't I seen this sort of thing on any other guitar, anywhere, ever?
I thought for a minute or two about replacing the 5-way on my strat with a stepped attenuator. Decided it was a pretty silly use for a $20 switch. As you've described it, you'll only be using one "step", but the concept is the same.
Are you going back to 2 pickups? Have you considered something like a DP3T rotary? You could probably get your existing knobs to fit. Might need a little reaming...
With 3 throws you could have: full volume - partial - off. The tone could work similarly with some predetermined middle point.
I was thinking more along the lines of old-fashioned lever switches, DPDT. Two of 'em for the volume of one pup (she's a quad-bucker made out of two soapbars wired together).
So my idea was for four total positions, giving me: Full, half, quarter, and half - the two half settings being a quirk of my current schematic.
Which is, by the way, as follows: Pickup wires run into CENTER pole of Switch A.
Wires run out of NORTH poles of A and into the CENTER poles of Switch B. Wires also run out of the SOUTH poles of A, the terminals of which are connected by a resistor of appropriate value, and the SOUTH wires from A run into the CENTER poles of Switch B.
Switch B is the same as Switch A, except that the wires go to the jack instead of another switch.
What say? Think this might work?
Last Edit: Jun 19, 2008 15:55:17 GMT -5 by nyteeye
The total value of the 2 resistors is essentially arbitrary. I'd suggest having the add up to 500K, like the standard pot on a guitar with humbuckers.
The relative values of the two depend on how much attenuation you're looking for. Setting them equal will give you 50% voltage output, but won't correspond to half volume. Volume pots are logarithmic, remember?
You might also want to hang a resistor (500K?) to ground off one of the lugs on the other side of the switch, to simulate a volume pot turned all the way up. Some people feel that without the load of the volume pot, the pickups will put out too much of the highest frequencies, sounding brittle or harsh or strident. I love the sound of my strat with no load, but it might not be best for bass.