Mixing Single Coi & Hummbucker with Blend Pot?

[BluesCam]

Hi everybody. I am trying to replace the pots on a guitar with a single coil lipstick pick up and a humbucker. It had a blend pot (only 3 poles) and a volume and tone control. All the pots are 250K. Would it be better to go to 500K and a two tier blend pot? As I understand it, you need a dedicated blend pot. Thank you.

[big_teee]

Hi everybody. I am trying to replace the pots on a guitar with a single coil lipstick pick up and a humbucker. It had a blend pot (only 3 poles) and a volume and tone control. All the pots are 250K. Would it be better to go to 500K and a two tier blend pot? As I understand it, you need a dedicated blend pot. Thank you.

Here's a wiring diagram you could use, for bass or guitar.
http://www.guitar-mod.com/wiring/jbass_mod.gif
250k pots are usually used with single coils.
500k pots are brighter sounding, and usually used with humbuckers.
You can use either, whatever sounds best for your application.
T

[Mick Bailey]

Is your existing blend pot is just a linear pot with each pickup taken to the respective outer lugs and the wiper as the 'hot' output?

A dual blend pot is like having a separate volume control for each pot and turning either one down while the other is being turned up. You also have a master volume, which is effectively paralleled with the blend pot. Think of the connections and you now have 3 pots in parallel. Effectively you end up with 83K resistance across your pickup, which will take the shine off your sound. 500k would be a better choice for the pots if you go for a dual blend control. Some people remove the ground connections from a dual blend to reduce pickup loading, though you can't get 100% isolation at either extreme of rotation.

Why not do the pickup swap first with your existing wiring and try it before deciding what to do? You never know, it may sound just fine.

[BluesCam]

Thanks for your replies guys! Let me clarify the wiring. It seems a bit strange. The neck pickup (lipstick) hot lead is wired directly to pot 1, terminal 3. The white wire from the 3 way switch is connected to terminal 2 and the ground from the lipstick pickup is wired to terminal 1 and shunted to ground. One pot 2, the humbucker hot lead is wired to pot 2, terminal 3, and the ground from the humbucker is wired to terminal 1 and shunted to ground. Pot 3 has a capacitor connected to terminal 3 and is shunted to ground. Terminal 2, has the main output (red) from the 3 way switch connected to it. Terminal 1 has the hot from the guitar jack connected to it. The shield from the guitar is grounded to the case of the pot. All three pots are grounded together. The ground from the 3 way switch is soldered to the case of pot 2. It seems like pots 1 & 2 are set up as volume knobs and if the 3 way switch is selected in the middle, they would work as blends. Does that sound right? I am keeping the pickups, but changing the pots. The originals are falling apart. They are rated at 500K. Measuring DC resistance on the pickups, I get 8K for the humbucker, 6K for the lipstick, but when they are combined it drops to 3.6K. What would you suggest as far as new pots and wiring? Thanks for your input!!

[big_teee]

Thanks for your replies guys! Let me clarify the wiring. It seems a bit strange. The neck pickup (lipstick) hot lead is wired directly to pot 1, terminal 3. The white wire from the 3 way switch is connected to terminal 2 and the ground from the lipstick pickup is wired to terminal 1 and shunted to ground. One pot 2, the humbucker hot lead is wired to pot 2, terminal 3, and the ground from the humbucker is wired to terminal 1 and shunted to ground. Pot 3 has a capacitor connected to terminal 3 and is shunted to ground. Terminal 2, has the main output (red) from the 3 way switch connected to it. Terminal 1 has the hot from the guitar jack connected to it. The shield from the guitar is grounded to the case of the pot. All three pots are grounded together. The ground from the 3 way switch is soldered to the case of pot 2. It seems like pots 1 & 2 are set up as volume knobs and if the 3 way switch is selected in the middle, they would work as blends. Does that sound right? I am keeping the pickups, but changing the pots. The originals are falling apart. They are rated at 500K. Measuring DC resistance on the pickups, I get 8K for the humbucker, 6K for the lipstick, but when they are combined it drops to 3.6K. What would you suggest as far as new pots and wiring? Thanks for your input!!

You might consider drawing out a diagram or schematic of your wiring.
Your long description is hard to follow.

If your guitar has a 3 way switch, and If it has a balance pot, I would remove the balance pot.
Replace the balance, with a second volume.
With 2 Volumes, you could have a 250k, or 500k for the Single Coil, and a 250k, or 500k for the humbucker.
Use a 500k Pot for the tone roll-off, do pickup switching with the 3 way.
I use this on my gear a lot!
If you wire the output from the 3-way switch, to Vol-1 & Vol-2 terminal 3, and put the pickup on terminal 2 then you will have independent pickup volume control.
Be sure to ground terminal 1 of the volume pots, that is what turns the pickup off when the volume is rolled back.
Probably use a .047uf tone cap, with a 500k tone Pot.
Some variation of this is what I would use.
http://www.kramerforum.com/wiring/19...r_imperial.gif
I have a pickup test bass, wired just like that.
Works great!
T

[BluesCam]

You might consider drawing out a diagram or schematic of your wiring.
Your long description is hard to follow.

If your guitar has a 3 way switch, and If it has a balance pot, I would remove the balance pot.
Replace the balance, with a second volume.
With 2 Volumes, you could have a 250k, or 500k for the Single Coil, and a 250k, or 500k for the humbucker.
Use a 500k Pot for the tone roll-off, do pickup switching with the 3 way.
I use this on my gear a lot!
If you wire the output from the 3-way switch, to Vol-1 & Vol-2 terminal 3, and put the pickup on terminal 2 then you will have independent pickup volume control.
Be sure to ground terminal 1 of the volume pots, that is what turns the pickup off when the volume is rolled back.
Probably use a .047uf tone cap, with a 500k tone Pot.
Some variation of this is what I would use.
http://www.kramerforum.com/wiring/19...r_imperial.gif
I have a pickup test bass, wired just like that.
Works great!
T

Sounds like a plan. Thanks BigTeee

[BluesCam]

I wired it up and it works fine. I used a .022 cap. Thanks for the diagram big-teee!