Coil tap switch for SR 705

I have an Ibanez SR705 and I have replaced the preamp with the Bartolini NTMB. I am now looking to upgrade the pickups. I am looking at the Bartolini MK5CBC dual coils. Has anyone here added a coil tap switch to their SR bass? Is there any way to piggy back on an existing control ( in the form of a dual function knob) or do I have to drill a hole and add another switch?
If anyone has added another switch on this bass where did you locate it in this already crowded control cavity? Also, I am looking at the Barts because, first, they are the obvious step up in this bass and second, because of the versatility the coil tapping will add. Are there any other pickups I should consider, specifically any that might add a somewhat more traditional sound to this bass and preamp? Thanks for your comments.
 
if you use your pickups in single coil mode, be sure to tap out a south coil from one and a north coil from the other. this way they'll hum cancel when your blend is in the middle.

push-pull pots are available in many values these days so there's a good chance you won't have to drill an extra hole. it should only take a single pole to coil tap, and push-pull pots virtually all feature double pole switches so you can have one switch for both pickups.

there may be fitment issues. you may have to remove a pot from a circuit board. perhaps you could post some pics of the electronics.

if you plan to have the pickups wired in series, you'll have a notice volume drop when you switch to single coil mode.
 
I want to have single coil, parallel and series humbucking switching capabilities.

If you want series/parallel/single switching, you'll likely need to go with a switch. If you want to stick to push-pull knobs and not modifying the looks of the controls, you'll have to choose 2 modes.

I added a series/parallel/single switch to my Ibanez GWB35 with a Bartolini NTMB preamp and a Bartolini pickup, much like the setup you're discussing here. With only one pickup and two knobs, things weren't crowded in the control cavity.

Series is appreciably higher output than parallel and single, and the biggest tone jump too.
 
  • Like
Reactions: cactus1
Has anyone here added a coil tap switch to their SR bass?
I did. It's a SR905. Chrome switches are pickup coil selectors. Black one is MID freq. center selector. All three of them are DPDT on-on-on mini toggle switches.
Bart NTMB+MK5+switches 1.jpg Bart NTMB+MK5+switches 2.jpg Bart NTMB+MK5+switches 3.jpg
 
001.JPG
Series is appreciably higher output than parallel and single, and the biggest tone jump too.
I did. It's a SR905. Chrome switches are pickup coil selectors. Black one is MID freq. center selector. All three of them are DPDT on-on-on mini toggle switches.
View attachment 1107945 View attachment 1107946 View attachment 1107947

It doesn't look like I have room in my control cavity to add 2 switches like that. One solution suggested was to add a balance pot with DPDT push pull lugs. This I assume will only give me 2 of the 3 possible configurations. Are these MK5 CBC pickups in this SR 905? How do you like them?
 
Last edited:
View attachment 1108032


It doesn't look like I have room in my control cavity to add 2 switches like that. One solution suggested was to add a balance pot with DPDT push pull lugs. This I assume will only give me 2 of the 3 possible configurations. Are these MK5 CBC pickups in this SR 905? How do you like them?
Is that the HR-5.4AP/918 prewired set or is it the HR-5.4/918 (no active-passive push-pull vol pot) prewired set? Seems you have the AP version (so the volume pot is already a push-pull pot), right?

I have no idea that there is such a push pull balance pot. Even if it exists, I'm imagining it would be too tall and wouldn't fit inside your SR series electronic cavity.

So your best bet would be changing one or two of the EQ pots to push pull ones.
 
  • Like
Reactions: cactus1
Is that the HR-5.4AP/918 prewired set or is it the HR-5.4/918 (no active-passive push-pull vol pot) prewired set? Seems you have the AP version (so the volume pot is already a push-pull pot), right?

I have no idea that there is such a push pull balance pot. Even if it exists, I'm imagining it would be too tall and wouldn't fit inside your SR series electronic cavity.

So your best bet would be changing one or two of the EQ pots to push pull ones.

I thought that BestBassGear used to have push/pull blends, but I don't see any on their website any more. They are the only retailer that I know of, which carries certain exotic pots. Indeed, a push/pull blend is a rare item.
 
  • Like
Reactions: cactus1
I thought that BestBassGear used to have push/pull blends, but I don't see any on their website any more. They are the only retailer that I know of, which carries certain exotic pots. Indeed, a push/pull blend is a rare item.

even if OP is able to get one, still it might be problem, looking at OP's picture of which the (common) volume push-pull pot seems almost as tall as the electronic cavity depth.
 
Is that the HR-5.4AP/918 prewired set or is it the HR-5.4/918 (no active-passive push-pull vol pot) prewired set? Seems you have the AP version (so the volume pot is already a push-pull pot), right?

I have no idea that there is such a push pull balance pot. Even if it exists, I'm imagining it would be too tall and wouldn't fit inside your SR series electronic cavity.

So your best bet would be changing one or two of the EQ pots to push pull ones.


Yes, the volume knob is a push pull for active/passive. The push pull balance knob was suggested by a moderator on the Ibanez SR forum and I haven't really spent much time looking for one yet, so, I am not sure if I can actually find one. This is the picture he included in his response to me.
BOURNS_250PP_SS.jpg
 
Yes, the volume knob is a push pull for active/passive. The push pull balance knob was suggested by a moderator on the Ibanez SR forum and I haven't really spent much time looking for one yet, so, I am not sure if I can actually find one. This is the picture he included in his response to me. View attachment 1108841

but will it fit the cavity depth?

secondly, you need to find the type of taper and value, which best resemble taper and value of the balance pot of your HR-5.4AP/918 prewired set.
 
View attachment 1108032
It doesn't look like I have room in my control cavity to add 2 switches like that.
Yeah, it looks like your bass has the output jack at the front so, the different cavity space. Mine has a side jack.
This I assume will only give me 2 of the 3 possible configurations.
Correct, only two choice with a push-pull switch.
Are these MK5 CBC pickups in this SR 905? How do you like them?
Yes they are. I like them, especially the versatility I get by switching coils and mixing them together.
 
  • Like
Reactions: cactus1
Nice work, but the pots are not grounded properly. There should be a ground wire daisy chained across the back of each pot. It will keep things working if a pot comes loose.

Actually, to me, this is the proper way of grounding the pot cases, by touching the shielding foil. I hate to see solder blobs on the pot casings. You never know who did it, how did it (Schrodinger's pot?) :)

Besides, this is my bass and I've done it myself. If a pot comes loose I'll fix it. But there are internal tooth lock washers under every pot. I don't think they will come loose easily. I know, everyone treat/abuse their instruments differently but in my case it's been years and they're still tight in their place.