More Capacitor Madness

Setup, repair and restoration of Rickenbacker Instruments

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rob_u
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More Capacitor Madness

Post by rob_u »

After a lot of great help from the people here I got the right Cap (.0047mfd) into my 360-12 and tried it out. A big improvement in the vintage sound, but a little harsh with my MXR Super Comp, and my Boss Acoustic Simulator. So I wanted to A/B the Cap sound with the original, and maybe a step in-between, so I set up an on-on-on mini-switch with a .0047mfd on one side, a jumper to allow a bypass in the middle, and a .01mfd on the other side. I didn't want to make any permanent changes yet, so I installed the switch (with a washer) into the fifth-knob hole (the pot is still wired in, just tucked inside).
I still have some more testing to do with the pedals, but it actually sounds pretty cool, the .01mfd is a good halfway point. This was only intended as am experiment but I may keep the switch - the only question is where to put it? I'd like the fifth knob back out, and I don't know if I want to drill into my pickguard (I suppose I could always get another one later), and I can't locate any 330k push-pull pots.
Any ideas?

Rob

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aceonbass
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Re: More Capacitor Madness

Post by aceonbass »

I couldn't find any push pull 330K pots either, so I guess no one makes them. I'd just use a 500K pot. If you stick with the swich, you can put it behind the 5th knob level with it, or down low between the pickup selector and bass volume.
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jps
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Re: More Capacitor Madness

Post by jps »

I would just replace the 5th knob with the switch; rolling back on the neck volume control does exactly the same thing as the 5th knob as long as you don't turn it fully CCW.
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beatlefreak
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Re: More Capacitor Madness

Post by beatlefreak »

Just use the 500k push/pull pot. You'll just get a little more range on your tone control.
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Re: More Capacitor Madness

Post by rob_u »

Hi Kris,

Thanks for your help again. I guess I worried that with a 500k pot in the volume position the sound would be too bright (I tried that with my Strat once). But I hadn't thought of replacing the tone pot. When you say that I will get a little more range, does that mean more treble, or will it bleed off more treble? The bottom line is will a 500k pot in the tone position alter the sound when the control is at the minimum?

Thanks, Rob
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beatlefreak
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Re: More Capacitor Madness

Post by beatlefreak »

The tone control in a guitar is a passive circuit consisting of resistance and capacitance. There is no active component (such as a tube or IC). As a result, it cannot boost anything - only cut. The cap and pot form a first order low pass filter which rolls off high frequencies above the cutoff frequency. The variable resistance offered by the pot moves this cutoff frequency within a range - The greater the resistance, the greater the range for the cutoff frequency.
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Re: More Capacitor Madness

Post by rob_u »

Thanks again for your clarification Kris. I've decided to replace the mixer pot, based just on control layout. I like having the push pull at the end, opposite the pickup switch, and I don't have to mess with re-soldering either of RIC's vintage-looking capacitors. None of my local stores had a 250k in stock, but the one where I bought my 360-12 had some on order, so I gave them my name, and I'll wait until it comes in. Until then the switch stays in place.

Rob
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aceonbass
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Re: More Capacitor Madness

Post by aceonbass »

Make sure you get solid shaft pots like the CTS pots RIC uses. The stock RIC knobs with the set screw won't fit a split shaft pot properly.
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Re: More Capacitor Madness

Post by rob_u »

"Make sure you get solid shaft pots like the CTS pots RIC uses. The stock RIC knobs with the set screw won't fit a split shaft pot properly."

I hadn't thought of that. I think that the pot that the store is ordering is a split shaft. I've done some online searches, and all I can find is split shaft. Do you have any idea where I can get one with a solid shaft?

Thanks
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Re: More Capacitor Madness

Post by aceonbass »

Rob, go to Guitar Parts Resource online. They have the proper solid shaft pots made by CTS that RIC uses. If the guy at your music store gives you any flak about cancelling your order, tell him he should have known thar RIC's don't use FENDER parts in them.
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rob_u
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Re: More Capacitor Madness

Post by rob_u »

Dane,
I checked Guitar Parts Resource, and they do have CTS solid shaft pots, but not with a push pull switch. It looks theirs are all split shaft too. I did bookmark the site for future reference though, their selection is excellent.
I did a little tweaking on an old TBX pot I had laying around, and found that if you spread the split out a little, and position the set screw on the split itself, it seats very well. When I get the pot, I might use a Dremel to put a slight dimple either on the split or elsewhere on the pot so that the set screw seats well.
The dealer in question (Huber and Breese) is one the better independent dealers here in Michigan. They would give me no hassle about it at all.

Thanks, Rob
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