Defective pot or...?

Setup, repair and restoration of Rickenbacker Instruments

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marcinkus
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Defective pot or...?

Post by marcinkus »

I own a '98 4003. I replaced the stock PUs with the vintage ones, plus I added the .0047 cap, and the bass is perfect but... there's a odd question I need your response about:

1) when the switch selector of my bass is upward OR downward, the pickup volumes work, everything works;
2) when the switch is in the middle and BOTH volumes are full open, the bridge PU has almost no output and it seems only the neck PU works; in fact, if I move the switch upward, the tone seems the same!
3) but if I turn down (a little) the neck PU volume, the bridge PU starts singing;
4) also, if don't turn the neck PU volume until the max the outputs are mixed well and everything works.

Could it be the neck PU pot or is this a common Ric bass peculiarity? My MIM Jazz bass doesn't behave this way! ;)

Thanks
'96 4004C | '98 4003 | '00 4003vp | '05 4003 Custom | '08 4004Cii
markthemd
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Post by markthemd »

The pickups are fine and you are certain that you are getting then indiviually ?

If the middle selection is thin ,and has a nasal quality to it ....you have a phasing issue .

The leads on one of the pickups are reversed and tha needs to be changed .A fairly easy thing to do .You will need a solding iron.

On ORIGINAL Fender Jazz Basses ... the neck pickup was reverse wound ,this gave you a hum canceling mode with both on and a thicker /more midrange tone .If you back off the volume on that USA version you get a thinner tone .
With the Mexican/Korean version ...I do not believe they are still winding one coil reverse.
This will give you the sound that your Jazz gives you .

As to the Rick ,I would do this ;

first clean the contacts on the selector switch .Sometimes they get tarnished and a piece of wet/dry sandpaper pulled through the contact are will wipe that away .(Byt the way ,we did this in the assembly area at the Kilson Drive plant all the time )
Next ,make certain that you do not have a cold solder joint .With a bad ground/earth connection this could be your problem.
The solder should flow when you heat it with an iron .When there is a lot of metal to heat you need to use a higher wattage iron .
Stay away from guns as they will demagnetize the pickups .
I have one ,I use it ,but not on the pickups .

It gets used for installing the ground wire on pots BEFORE the pickups are around and for soldering the ground/earth wire on Strat type trm claws.That is it ....except for the Switchcraft Rick style switch that has NO lug (unlike Gibson) to solder to .

I think you have a simple problem .Answer some of this and get back to me .
So you too want yours "ALAPWOB"?!?!
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marcinkus
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Post by marcinkus »

Could it be the .0047 cap? I didn't try the bass without it...
If somebody has a 4001v63, can he please give me his response?
'96 4004C | '98 4003 | '00 4003vp | '05 4003 Custom | '08 4004Cii
markthemd
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Post by markthemd »

iif you put the cap in then you get a totally difference tone .

Some caps really cut the low end and pickups with a real low output either from low coil windings or weak magnets get the crispy tone .Actually there are so many combinations to this .

The 4003 without the cap gives you maximum outout .

I would suggesting ,just cleaning the contacts .
then if you have any kind of soldering skills ...tackle the phase issue .

To do this you must be gentle .

Remove the bridge pickup (it is easier to work on ) and find the two wires coming off the coil.
Unsolder them from the shieled cable going to the controls/pickguard.
Take the wire that was soldered to the 'hot' and solder it to the lug on the black plate with the ground/earth of that cable .
Now take the wire that was the ground/earth wire and solder it to the hot of the shielded cable .
reinstall the pickup ,tune and set the switch to the center .....does it sound like you are holding your nose with your fingers and talking ?

THAT is electrical "out of phase"

Is it clean and smooth and full? that would be electrically "in phase"

If switching it made it worse , then re move the pickup and put it back the way it was .

If it really bugs you ....have some one ( like me ) rewind the pickup reverse .This will give you a thicker tone with both on and a humcancelling mode with the switch in the middle .

some players like this a lot .It gives them a 'safe' sound in a room that picksup all the 60 cycle (USA) or 50 Cycle (Europe) with single coil pickups .It's not perfect ...but it does help.
So you too want yours "ALAPWOB"?!?!
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Post by marcinkus »

The PUs work perfectly, they aren't out of phase...

I removed the .0047 cap but it didn't solve the problem. The scatterwound toaster cuts the horseshoe's output (using them both at full volume). I am thinking to replace the neck vol pot.

Mark, can I ask you how the pot interacts?

Thank you
'96 4004C | '98 4003 | '00 4003vp | '05 4003 Custom | '08 4004Cii
markthemd
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Post by markthemd »

The pot has NOTHING to do with this .

Clean the switch contacts

Then go to a Radio Shack or an electronic component supply house and get a can of 'Tuner cleaner WITH lubricant'.

Spray that into the pots .

The adjustments for the pickups are as follows;

Press ALL 4 string down at the last fret and adjust the pickups with your other hand.

set the neck pickup to maximum ,don't over tighten it or the guard will crack .In your case ,you might leave the top of the pickup 1/8" away from the strings .

Next set the treble side as close to the pressed down string as you can ,then set the bass side of it about 1/8" lower .

Does that change the sound ?

Is it the same ?

If this does not do anything ...time to see a tech.This guessing is hard to give you a definitive answer.

Maybe John Hall can give you some kind of tip .I am at a lose for an idea at the moment.
So you too want yours "ALAPWOB"?!?!
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Post by marcinkus »

I sprayed the lubricant some days ago and I adjusted the pickups as you told me, but nothing changed. My luthier (he is one of the best here in Italy) said he never tried a RIC bass with vintage PUs and he thinks it's a Rickenbacker bass sound balancing peculiarity. But how is it possible? Why the voulmes interact this way only when they're full open? When I drop them a little the bass works perfectly!

Hope Mr. Hall could give me some hints

However I thank you, Mark
'96 4004C | '98 4003 | '00 4003vp | '05 4003 Custom | '08 4004Cii
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Post by marcinkus »

I was reading some posts here in this forum when I found the topic "Rick 4001 Questions" (02/14/2001), where Mr.GT had a analog problem.
However, while I don't get a dramatic loss in volume when using both pick-ups (as he said), the neck pickup becomes the more prominent of the two.
I begin thinking my luthier is right.
'96 4004C | '98 4003 | '00 4003vp | '05 4003 Custom | '08 4004Cii
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Post by marcinkus »

Bad news, guys: the neck vol pot is dead! I didn't touch anything but it does not work anymore. So I tried to call the Italian RIC dealer to buy some of these pots (my town's music shops sell only the fender kind and I'd like to keep my bass as original as possible) and... it's the same old story: they don't import these items. Isn't it incredible? I can't buy a 250k pot! I sent a E-Mail to Mike Parks and I hope he could help me! I'll let you know...
'96 4004C | '98 4003 | '00 4003vp | '05 4003 Custom | '08 4004Cii
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Post by rick12dr »

Marcello,
Just my 2 cents here, but in the interest of simply getting your bass back in business, I'd bite the bullet, and dont worry that you "don't have a real Rick pot". As long as you have a solid shaft 250K pot, you're OK.Besides, you don't have a truly "vintage collectible" Rick, and no one will really care. Kinda like new sparkplugs for your car.
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Post by markthemd »

Buy the Fender pot ...both FENDER and Rick use CTS pots .

Take the wiper out of the Fender pot and install it in the Rick casing .

I do this all the time .

Tools needed ....pair of pliers and a small slot head screwdriver and a soldering iron .

No electrician needed ,no college degree...

Easy to take care of .
So you too want yours "ALAPWOB"?!?!
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Post by marcinkus »

Thanks Mark...
Yesterday I was looking at Mike Parks' RicPage: as you know, he sells original RIC electronics, and I found he had only one kind of pot. The pot is the #07341 (500k) and it is universal.
I thought 4003 basses had two 250k volume pot and two 500k tone pot... Am I right? Now, should I buy a 250 or a 500k pot?
'96 4004C | '98 4003 | '00 4003vp | '05 4003 Custom | '08 4004Cii
markthemd
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Post by markthemd »

Get either ...pots are like windows ,the larger the window the more the curtain can open to 'see' the sound .

A 250K pot will 'restrict' this .
In some cases this is fine ,especially if you are using a guitar with a Gibson style humbucking pickup and two single coils /strat types .

In the Rick ....in the 1960's there were in fact two value pots and they also used solid shaft and split shaft with knobs that used a set screw to mount them .
SCREWY!!!!!!!!!!

Now , they use solid shaft pots with the same knobs (makes sense as the split shafts do collapse when you tighten the set screw ).

The value ....I'd have to go to the site and check .
So you too want yours "ALAPWOB"?!?!
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Post by marcinkus »

I see but how can I tell the 250k pot from the 500k? Looking inside my 4003 they seems to be the same.
'96 4004C | '98 4003 | '00 4003vp | '05 4003 Custom | '08 4004Cii
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Post by markthemd »

You can not from the markings on the can usually .

There will no doubt be a series of numbers somewhere on the can of the pot ...this will start with 137 that is the code for the CTS brand of potentiometer. The other four numbers indicate when it was made and what plant .

From the Rick page of schematics ,it says to use a 250K pot for volume .

The trouble you have may be a cold solder joint or , a fur ball of crud in the pot .This is really easy to fix .
So you too want yours "ALAPWOB"?!?!
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