New lefty 4003 owner with electronics question...

[Addison]

Howdy!

I am now (finally) a 4003 owner, and, although the process was quite long and ot took a couple of basses before I found one that was solid, I honestly couldn't be happier.

I picked it up from Wildwood Guitars in CO, and they made the experience wonderful. They really picked out a good one for me. The first one I had had many issues (a bad neck being the most important) and the dealer experience wasn't the best... but I'm glad I decided to give it another go, and I'm really glad I did. The bass I have now is AMAZING... I love, love, LOVE it.

Anyhoo...

As some of the more knowledgeable electronics gurus in here know, Rickenbacker does NOT use reverse audio taper pots in their lefty instruments, but they still wire them lefty. This practice makes the tone control useless... it's either off or on. The volume taper is a little better, but not that good either. (For the record, neither Fender or Gibson use correct pots or wiring either. I bought a several thousand dollar Fender CS bass and it had standard pots wired lefty too.)

To get the most out of the electronics, I'm faced with two options...

1.) Rewire it to righty orientation... the pots will then work as they're supposed to.
2.) Replace all the pots with reverse audio taper pots and wire it lefty. * This is my preferred solution *

Since Rick is now using 330K pots... one of which is a push/pull... unless I pay $100+ dollars a piece for custom made pots, I will NEVER be able to find reverse audio taper pots with that value.

However, 250k and 500k reverse audio taper pots are actually quite easy to find, so I was thinking about wiring my 4003 up they way they were more recently wired with 500k tone pots and 250k volume pots. Doing this I would lose the vintage push/pull feature, but I'm totally OK with that.

Since I'm increasing the tone pots and decreasing the volume pots, what kind of tonal change can I expect from where I'm at now with having all 330K pots? Did Ric change to 330K pots to meet in the middle and not have to stock so many different kinds of pots? Can I expect a similar tone?

Another possible option I have is to leave the volume pots stock and change both tone pots to 500k or 250k reverse audio taper pots...

Any insight would be greatly appreciated!!!

Thanks!

I absolutely LOVE the way it sounds as-is... so I'm tempted to just reverse the wiring and call it a day. But

[cassius987]

Am I mistaken under the impression that pots don't technically have an orientation? The way I always thought about it, the center lug is wired in series in between both outer lugs connected by a strip length-based resistor. Favoring the pot dial clockwise decreases resistance from the center lug to the clockwise-side lug, and vice-versa. If you wire the ground to one lug, favoring that side kills signal, whereas if you wire the "pass" to that lug, favoring it should increase volume by getting you away from the ground. It's not about what side the lug is on, or at least I think it's not. So I don't see how reversing the wiring has rendered anything useless? Forgive my ignorance. If I remember right I have used reverse wiring before, many times for different purposes, and that didn't really change function as far as I could tell.

I would consider just reversing the wiring if there really is a problem. Cheaper, easier and you will get to see what you think of the sound before spending additional money. Besides, I think the old 250k/500k setup doesn't sound all that great, especially with the new pickups. When you have two 250k pots wired in parallel for volume, they load down to 125k. That will work out alright for low impedance pickups but Rickenbacker 4003s have pretty hot single coils these days. If you had to get new pots I'd consider 500k all around, as they will all load down to about 250k in the circuit (respective to tone and volume) and that puts you in P Bass territory.

[Addison]

I can't claim to be an expert here either... far from it.

But i have learned through reading and experience that linear taper pots can be wired either way and work fine... logarithmic pots, or audio taper pots, can not.

I've switched volume pots out for linear taper lots and have had success wiring them lefty, but tone pots require the use of audio taper pots and they only work correctly when turned clockwise and wired righty. Wired "lefty" and turned counterclockwise, they almost act like an on-off switch. It goes from 0-10 in the first 10% of rotation.

They do have "reverse audio taper" pots that can be used for lefty tone controls and wired lefty and turned CCW for a smooth taper the goes from 0-10 through the full rotation of the knob.

I don't know the specifics as to why... I'm assuming it has to do with the wiper, but... I'm not an expert at all.

[jps]

Correct, audio taper pots have a non linear way of working compared to "standard" linear pots. You would have to get normal or reverse depending on which direction you want them to work for you.

[johnallg]

It is the way the resistive element is doped. Linear taper is just that, constant across the element. Log or audio taper has the element with the resistive material more at one end and less at the other, so reverse wiring it will act as you said you've experienced. If you replace with lefty audio taper pots, use the 500k for tone. 250k would be not as pleasing tonally, whereas the 500k would be closer to the stock.

[cassius987]

D'oh, totally forgot about the audio taper!

Yet another reason to add to my list of why I prefer linear pots...

[aceonbass]

I don't know why RIC went to the universal pot. It's not like they had a lot of different values before. I mean, ya got 250K & 500K. I think they're the only major guitar builder that does that. Before the universal pot, the ones I used to get from RIC were all in the 180K range, even though I'm sure I must have been ordering both values back then. Now that I do so much guitar wiring I'm hearing the difference though by using 250&500K that are within 10% of spec, and different values than the universal .047 tone cap that comes in all things RIC. I no longer have all the knobs turned up all the way to get the tone I'm looking for. Now there's a little something in reserve on the tone control, which gives me more options. The universal pot and tone cap is a virtual tone suck on a 4004 bass (one of the main reasons people don't hang onto these basses). I'd definitely replace the pots in your 4003 with leftys of the 250&500K values.

[Colonel Sanders]

Am I mistaken under the impression that pots don't technically have an orientation?

You are absolutely right for linear pots. These do not have an orientation. Audio pots do as the resistance is non linear (the resistance on the pot track increases logarithmically).

[Wiker]

I have a 4001V63 LH that was originally lefty wired, and for me that was very confusing. My ’79 4001 LH, I’m not sure if it was originally lefty wired. I have them both rewired the right way.
For everything else in the world knobs are turned clockwise to increase and counter clockwise to decrease, and has nothing to do with which hand is used to turn the knob. To me the idea of “lefty” wiring is strange and counter intuitive.
So , I vote for option 1.) Rewire it to righty orientation...

[Addison]

Cool... thank you guys so much for the replies!!

I'll try replacing tone pots with 500k and the volumes with 250k pots.

Can anyone comment on how that might change the tone, if at all? I won't be bothered if it's only something that can be picked up with a spectrum analyzer... if the differences will be very minimal, I'll be fine.

I have a 4001V63 LH that was originally lefty wired, and for me that was very confusing. My ’79 4001 LH, I’m not sure if it was originally lefty wired. I have them both rewired the right way.
For everything else in the world knobs are turned clockwise to increase and counter clockwise to decrease, and has nothing to do with which hand is used to turn the knob. To me the idea of “lefty” wiring is strange and counter intuitive.
So , I vote for option 1.) Rewire it to righty orientation...

I totally hear you... it makes logical sense as to how the knobs "should" be turned (CW vs CCW), but for me, it's the motion of my hand that makes all the difference.

When I turn a knob UP, my left hand wants to rotate my fingers under the knob, toward the back of the bass... it makes enough sense to me that way as to where the motions become unconscious movements... at this point it's all muscle memory, and the only way I think I could shake it would be to rewire all of my basses back to righty. That's not going to happen.

Whenever I have knobs wired righty, I almost ALWAYS turn them the way that "feels" right to me first, before I realize that it's supposed to be the other way... if that makes any sense.

[ken_j]

If I recall correctly the original pot RIC used for "pull for vintage tone" was a 500k ohm Alpha. I may still have a used one, I would have to look but you should be able to find one new as long as it is not a reverse taper.

[aceonbass]

Changing the pots out to the values you specify will have the effect of "opening up" the tone, giving you more clarity. It now seems as if the tone controls do more. i now run my GK 2001RBP preamp flat with all tone control coming from the bass.

[Baker69]

I have the same issue with my Fender USA Jazz lefty as well with the controls working the other way round, it doesn't really bother me any more it's just something I got used to so when I got my 4001 and 4003 Ric lefties it was no big deal.

I hadn't really noticed any problems with the wiring on my 4003 lefty in relation to the tone/voume operation, they seem to operate smoothly and gradually?

[cassius987]

I'll try replacing tone pots with 500k and the volumes with 250k pots.

My opinion is the two 250k pots are too small to run two volumes in parallel with two pickups as hot as the ones on a new 4003, whereas 500k is more than enough for the tone caps... in fact I would not be too worried if these values were swapped (and possibly try a smaller cap value). Dane probably disagrees with me about this. However I feel the volume pot is the more important of the two in determining the final sound (not all important, just more important) and using two 250ks results in the low value of 125k which I think will make things sound darker than they have to.

[aceonbass]

I don't pretend to know the math and science that goes on in the different combinations of parts and specs. In fact I only half understand it based on what people who know more than me have taught me. I went from having all the controls on my 4003 at full, to backing off a bit on the tone controls when I swapped pots out for more traditional vales. Now of course the bass' electronics and pickup arrangement has completely morphed into something different altogether. I couldn't say whether or not the volume is more important than the tone control for determining the final sound, but then I don't even really understand the signal flow through a traditional 4003 wiring harness, and how the tone controls and caps interact with the rest of the wiring when they're not really even in the direct signal path between the pickups and the output jacks. My latest project, deciphering the 4002's wiring for an upcoming restoration I'm assisting with, actually makes more sense as the signal path is linear from the pickups to the output jacks. This is one schematic where the tone controls, with their hi and low pass caps at either end, definitely are the deciding factor in the final sound. As far as 250K pots being to low and making the new and hotter pickups sound darker, I have to disagree. I put a pair of late model unbuttoned guitar hi gains in a 4004 with the usual 4-control 4003 style harness with corrected pot values, and the bass nailed the early "Geddy" tone when playing Free Will. Dark, the 250K pots were not.
Anyway Chris, there are sources out there for lefty pots, so just pick some up and wire them in exactly in place of what you have. That should correct the problem.