[Rickenbacker 4003] RWRP Bridge Pickup Mod Tutorial

[drewphishesp]

do you flip the magnet over as well?

 

[Tipper]

A few years ago I remember RIC corporate forum member BlueAngel posted that he had done an RWRP modification to his c. 2006 4003's bridge pickup. This mod essentially puts a 4003 on the same plane as a Jazz Bass as far as hum canceling, i.e. when both pickups are on, at the same volume and in the same phase there is significant 60 Hz hum reduction. Under other conditions (unequal volumes, 0.0047 cap in-line) the hum canceling won't happen.

I was intrigued by this mod. I had noticed the occasional hum issue with my 2007 4003, although it was not a frequent problem. It mostly happened at home and not at gigs. On the other hand, why wouldn't you want the option to cancel hum, when needed? For rock music, where I typically use both pickups full-on, it seemed like an ideal situation. After reading BlueAngel's description I tackled it and came out successful. But I was nervous doing the job; that I got it right the first time was a bit of skill and probably a bit of luck. Either way I was spared some frustration. The result was not even a slight change in tone, just an OCD-soothing absence of hum in the pickup blend mode. Years later this pickup configuration is still going strong for me; I recently gigged the 4003 and it was a show-stopper. Lots of compliments.

I recently decided to do this again for a second bass. It's the second time I've done this mod and I've made a photo tutorial for others who want to do the same.

1. Measuring the pickups--two single coils with fairly similar resistance are ideal for canceling hum.
View attachment 1767273
View attachment 1767274

2. Observe what the bottom of the pickup looks like for reassembling it. An eyelet connects the ceramic magnet to ground, as well as the lead shield and a second eyelet that grounds the pickup surround. Closer inspection of the primary eyelet shows the grounded end of the coil soldered to it and the hot end of the coil in a heatshrink-covered joint with the lead wire. These joints will have to be spliced.
View attachment 1767275
View attachment 1767276

3. I like to "label" the stock ground wire of the pickup coil with a piece of Scotch tape. This will be spliced back as the hot wire after reassembly. Cut the hot and ground connections on the coil side leaving a 0.5'' section behind so you can strip them later and have a decent-sized lead.
View attachment 1767277

4. Remove the bobbin from the magnet and label the side that faces the bobbin "RP" (for reverse polarity). Rotate it 180 degrees horizontally, and put the cut leads back through the same holes in the magnet.
View attachment 1767278

5. Remember to line up the bobbin and the magnet so that the screws will connect.
View attachment 1767279

6. Reassemble the magnet, bobbin, and phenolic baseplate. Put heat shrink on the coil leads before soldering them in their new configuration (the one with the Scotch tape on it goes to the pickup lead wire).
View attachment 1767280

7. This is how my pickup looks after reassembly. I measured it with the multimeter and it measures about 100 ohms higher than before--probably heat from the soldering iron creeping into the coil. In a few hours it will go back down to the room temperature value.
View attachment 1767281

There you have it! Just some free info for those seeking it... hope it helps you, whoever you are.

cassius

 

[Tipper]

I'm coming to this RWRP Modification Tutorial YEARS after it was first posted, so please humor me and address this matter YET AGAIN.

Because I'm not sure whether the POLARITY of the Magnet resides on the SHORTER EDGES of the Magnet or on the FACE of the Magnet -- and because I'm NOT SURE what Posters mean when they variously refer to "FLIPPING", "TURNING", "ROTATE … 180 Degrees HORIZONTALLY", etc. -- I need to establish AGREEMENT regarding what those terms mean in the context of this Tutorial.

I take "FLIPPING" to mean Flipping the Magnet over like the pages of a Calender, from one month to the next.

I take "ROTATING 180 Degrees HORIZONTALLY" to mean turning the Magnet -- as it lies on its Face -- like the hands of a Clock, so that the SHORTER EDGE of the Magnet at 9 A.M. winds up at 3 P.M., after completing an ARC of 180 Degrees.

After separating the Bobbin from the Magnet, and CUTTING the Hot and Ground and Lead Wires -- making sure to distinguish them with Scotch Tape, for purposes of Reversing and Heat-Shrinking them -- I should FLIP the FACE of the Magnet Over (and Mark the Face that previously sat against the Bobbin as RP), before I "put the Cut Leads back through the same Holes in the Magnet." Yes?

THEN I run those Leads through the Phenolic Baseplate, reattach the Baseplate, Magnet, and Bobbin, and put Heat Shrink on the Coil Leads before soldering them in their new configuration (the one with the Scotch Tape on it going to the Pickup Lead Wire).

I would appreciate anyone who has successfully accomplished this Modification to confirm or correct my understanding of how to proceed --utilizing my Definitions, for purposes of clarity.

Also, CAN anyone tell me WHERE, on the Magnet Rickenbacker uses, the Polarity resides? On its Faces? Or on its Shorter Edges?

Thank you.

C.K. Tipper

 

[scotch]

Rotating as you described changes nothing. You do have to flip the magnet so that the face closest to the strings is now closest to the back of the bass. Rick' pickups have the magnet glued on, so be careful. Although I know the older pickup magnets have a little 'give' to them (my 1975 was when I performed this surgery), I'm not sure how brittle current Rick' production magnets are. Also the hot and ground wires need to be switched.

I had to get a little creative with my magnet and baseplate to make the wiring fit without pinching. I drilled my magnet very slowly to give access to my wires as I recall.

Best mod for a 4001/3 in my opinion. Shielding is a great move, too! I love the both pickups on sound!

 

[enewbold]

OK guys, I am about to try to make this mod on my brand new 2018 Ric that hums real loud, just like the older models. Will report back later with the results.

 

[Sparky Mark]

Apologies for the thread hijack but I'm seriously considering buying a 4003S. However, with all the negative issues around hum, maybe inadequate shielding, perhaps replacing (with a Nordstrand) the low output neck pup (as compared to bridge pup), probably needing to buy and fit a bridge pup bezel after removing the cover, bridge lifting and perhaps other problems I've yet to discover (did I read somewhere paint finishes not drying?) I'm having second thoughts.
I demo'd a new 4003 last Friday and whilst I didn't hear the hum (low volume in store) the output imbalance between the two pups was extreme; the neck about half that of the bridge).
Looks like I'll have to find one secondhand in order to afford the mods. Shame that a brand new bass in this price range needs such attention.

 

[sunbeast]

Apologies for the thread hijack but I'm seriously considering buying a 4003S. However, with all the negative issues around hum, maybe inadequate shielding, perhaps replacing (with a Nordstrand) the low output neck pup (as compared to bridge pup), probably needing to buy and fit a bridge pup bezel after removing the cover, bridge lifting and perhaps other problems I've yet to discover (did I read somewhere paint finishes not drying?) I'm having second thoughts.
I demo'd a new 4003 last Friday and whilst I didn't hear the hum (low volume in store) the output imbalance between the two pups was extreme; the neck about half that of the bridge).
Looks like I'll have to find one secondhand in order to afford the mods. Shame that a brand new bass in this price range needs such attention.

I have done all those mods to my Rics, but by no means will you NEED to do them. There are plenty of folks happy with most of the design choices.

The non-subjective “flaws” to look out for are finish bubbling around the edges of the bridge or an older bridge that is rising a lot at the rear (the bridge design was reinforced a bit at some point). Newer bridges still don’t always sit flush against the body at the rear but are cast in a way that they are unlikely to bend over time. The bubbling finish is arguably the worst of issues with modern Rics, and seems to mostly occur on colored basses where the bridge pinches into the finish on some basses. This might be a reason to specifically buy used, as you’ll be more likely to know if your bass is one of those afflicted (it seems to take some time to appear).

The pickup inbalance is inherent to the stock pickups design- the bridge pickup has a much larger magnet than the neck so the neck will never have the same output. You’ll need to switch out one or both pickups if this is a deal-breaker for you. The bridge pickup surround is only an issue if you take off the bridge pickup cover (the part that goes over the strings) and want something to visually take its place or give you somewhere more comfortable to place your thumb if you are a finger-style player. The hum is also not necessarily an issue- the majority of Ric players haven’t done this mod, and if you single either of the pickups it doesn’t have any effect on the noise level. Shielding is nice, but not always necessary- my 4003 isn’t shielded but was plenty quiet for me with the RWRP mod (which is free to implement). It wears Classic Amplification pickups now, but the stock pickups were only a little noisier.

 

[Archiverat]

I have two questions about this mod:
1. When you say "rotate the magnet horizontally," by that, do you mean (a) flip the magnet upside-down, so that the side that was flush against the bobbin is now facing away from the bobbin? Or do you mean (b) *turn* the magnet so that the end that was pointing to the right is now pointing to the left, and vice-versa, or (c) are you doing both of these things, in other words, so that the face that was once flush against the bobbin is now facing away from it *and* the end that was pointing to the right is now pointing to the left?
2. Can this procedure be done with the neck pickup instead, and, if so, would the instructions be the same?

 

[sunbeast]

I have two questions about this mod:
1. When you say "rotate the magnet horizontally," by that, do you mean (a) flip the magnet upside-down, so that the side that was flush against the bobbin is now facing away from the bobbin? Or do you mean (b) *turn* the magnet so that the end that was pointing to the right is now pointing to the left, and vice-versa, or (c) are you doing both of these things, in other words, so that the face that was once flush against the bobbin is now facing away from it *and* the end that was pointing to the right is now pointing to the left?
2. Can this procedure be done with the neck pickup instead, and, if so, would the instructions be the same?

Yes flip the magnet 180 degrees so that the side glued to the bottom of the bobbin (facing towards the strings when installed) is now facing the back of the bass when installed. The left/right orientation doesn't matter at all. You can do this on either pickup, you just have more wire to work with on the bridge pickup generally for swapping the lead and ground wires. Of course also make sure that the wire that grounds the pickup ring (or the pickup casing in the neck pickup’s case) is being sent to ground when you swap the lead wires from the pickup!

 

[Archiverat]

Thanks, Sunbeast. I did the mod on the bridge pickup, after all (not the neck pickup). Success! The pickups now hum-cancel when both engaged at full volume. (It's amazing how the hum roars back by just rolling back one of the volume knobs)

I found I did have to flip the pickup the long way (so left faces right and vice-versa) in order for the holes to line up properly. For anyone else viewing this thread, I found this image on another thread that clarifies it.

Also, I have a question for anyone about splicing wires:
Normally, I splice wires by twisting them together in-line (then applying a drop of solder and sliding the heat-shrink tubing over it) and that's how I did it in this mod.
Could the exposed ends of the wires instead be lined up parallel and twisted together to form a "Y"? It seems easier.

 

[radapaw]

Also, I have a question for anyone about splicing wires:
Normally, I splice wires by twisting them together in-line (then applying a drop of solder and sliding the heat-shrink tubing over it) and that's how I did it in this mod.
Could the exposed ends of the wires instead be lined up parallel and twisted together to form a "Y"? It seems easier.

splice like your life depends on it:
How-To: Splice Wire to NASA Standards | Make:

 

[sunbeast]

Thanks, Sunbeast. I did the mod on the bridge pickup, after all (not the neck pickup). Success! The pickups now hum-cancel when both engaged at full volume. (It's amazing how the hum roars back by just rolling back one of the volume knobs)

I found I did have to flip the pickup the long way (so left faces right and vice-versa) in order for the holes to line up properly. For anyone else viewing this thread, I found this image on another thread that clarifies it.
View attachment 3364304
Also, I have a question for anyone about splicing wires:
Normally, I splice wires by twisting them together in-line (then applying a drop of solder and sliding the heat-shrink tubing over it) and that's how I did it in this mod.
Could the exposed ends of the wires instead be lined up parallel and twisted together to form a "Y"? It seems easier.

Good work! I meant that the right/left orientation didn’t matter at all in the sense of magnet polarity, but yes depending on which way you flipped the pickup (longways or shortways) you would have to turn it to line the holes up as you found out. I always splice wires the “Y” way because you can use the tension to twist them together more tightly this way. This is the more common way to splice and you can still use heat-shrink effectively as long as you don’t overdue the amount of solder

 

[krfoss]

I just attempted this mod, followed the directions as accurately as I could, and I'm now not getting any sound from my bridge pickup.

Thats also not totally true. I hear a garbled, quiet, faint tone of the note if my thumb makes contact with the metal surrounding the treble pickup. I'm assuming the grounding was screwed up somewhere.

With that said, to be clear, I cut the two wires coming from the coils, then essentially switch the wires they were originally connected to? i.e. A to B and B to A?

Any other suggestions on why its coming out this way?

 

[sunbeast]

I just attempted this mod, followed the directions as accurately as I could, and I'm now not getting any sound from my bridge pickup.

Thats also not totally true. I hear a garbled, quiet, faint tone of the note if my thumb makes contact with the metal surrounding the treble pickup. I'm assuming the grounding was screwed up somewhere.

With that said, to be clear, I cut the two wires coming from the coils, then essentially switch the wires they were originally connected to? i.e. A to B and B to A?

Any other suggestions on why its coming out this way?

My first guess is that the wire that grounds the pickup ring is now attached to the hot lead and not the ground lead? If you cut and splice the coil wires before the connection to this ground wire then that’s all you should need to do (in this case you are just swapping the coil wires from the pickup). If you spliced the original ground connection after the wire that grounds the pickup ring (if you cut the wire after the little screw terminal) then you’ll need to fix that! It’s also possible one of your splices is not solidly connected now or is grounding out somewhere. Use a multimeter to check continuity

 

[krfoss]

My first guess is that the wire that grounds the pickup ring is now attached to the hot lead and not the ground lead?

It does seem to be a ground issue, but I followed the instructions as clearly as I could. I'm attaching a picture of what it looks like now. I've removed the insulation. The middle hole wire (ground) is now going to the hot lead (ie, into the control cavity). Thanks for your help .

 

[sunbeast]

It does seem to be a ground issue, but I followed the instructions as clearly as I could. I'm attaching a picture of what it looks like now. I've removed the insulation. The middle hole wire (ground) is now going to the hot lead (ie, into the control cavity). Thanks for your help .

Ah I see and should have immediately guessed the issue since it is ridiculous for Rick to wire this way (I haven’t had the stock pickups on my Rics for awhile so forgot!): the ground lead on the wire going into the control cavity is actually the wire shielding wrapping inside that gray insulated wire. It should be wound up and soldered directly to the plate of that screw terminal where your ground lead attaches- you can actually see some of the strands where this connection broke on your picture (see the pictures from the original post on this thread for how it should be attached). Using the wrap wire to make a connection like this on a moving part is silly and weak, and a common break point. You’ll probably want to cut some of the grey insulation off to expose more of the wrap wire, then carefully roll it in your fingers to simulate a stranded connection wire and solder it to that star terminal on the back of the pickup. Or you can just cheat and run a separate ground wire from that terminal to the control cavity and soldered to the back of one of the pots

 

[krfoss]

Ah I see and should have immediately guessed the issue since it is ridiculous for Rick to wire this way (I haven’t had the stock pickups on my Rics for awhile so forgot!): the ground lead on the wire going into the control cavity is actually the wire shielding wrapping inside that gray insulated wire. It should be wound up and soldered directly to the plate of that screw terminal where your ground lead attaches- you can actually see some of the strands where this connection broke on your picture (see the pictures from the original post on this thread for how it should be attached). Using the wrap wire to make a connection like this on a moving part is silly and weak, and a common break point. You’ll probably want to cut some of the grey insulation off to expose more of the wrap wire, then carefully roll it in your fingers to simulate a stranded connection wire and solder it to that star terminal on the back of the pickup. Or you can just cheat and run a separate ground wire from that terminal to the control cavity and soldered to the back of one of the pots

Thanks for this description. Aside from this loose wire in the grey insulation that'll be soldered to the star terminal, does it seem like my connection are done correctly? It seems like the "after" picture in the main photo shows the wire coming from the small side hole goes to the black wire in the grey insulation, whereas mine is going to the star terminal. It would have been nice if the original photos werent taken with a potato, however it seems others have been able to do this mod just fine...

 

[sunbeast]

Thanks for this description. Aside from this loose wire in the grey insulation that'll be soldered to the star terminal, does it seem like my connection are done correctly? It seems like the "after" picture in the main photo shows the wire coming from the small side hole goes to the black wire in the grey insulation, whereas mine is going to the star terminal. It would have been nice if the original photos werent taken with a potato, however it seems others have been able to do this mod just fine...

I can’t make out the last picture well enough, but he said the “wire with the scotch tape goes to the hot lead”, and the wire with the scotch tape is the one coming through the center hole...as long as you know you switched the wires and flipped the magnet you’re good. If you didn’t you’ll be able to tell with both pickups on all the way

 

[krfoss]

I can’t make out the last picture well enough, but he said the “wire with the scotch tape goes to the hot lead”, and the wire with the scotch tape is the one coming through the center hole...as long as you know you switched the wires and flipped the magnet you’re good. If you didn’t you’ll be able to tell with both pickups on all the way

Thanks so much. I'll solder on the loose wires tonight and report back. I took some more detailed photos of my process, so if I get it to work I'll post them for others.

 

[krfoss]

I can’t make out the last picture well enough, but he said the “wire with the scotch tape goes to the hot lead”, and the wire with the scotch tape is the one coming through the center hole...as long as you know you switched the wires and flipped the magnet you’re good. If you didn’t you’ll be able to tell with both pickups on all the way

You nailed the diagnosis. It seems the ground was never attached and just wedged in place creating contact but falling off when moved. I never knew it was supposed to be connected!

I soldered the ground on the star terminal and everything worked perfectly. Silent as can be. My heart stopped for a second when, going back to play a little later, the neck pickup stopped working until I realized I had my mono Jack in the rick o sound outlet. Stupidness continues.

This mod is great for anyone considering. Worth the extra effort.