Whats wrong with this schematic?

[idsnowdog]

I have been trying since noon to iron out this wiring but still it doesn't work! I have a JB Jr in the bridge wired correctly and two singles wired correctly. The 5 way switch works fine but I get interaction between the first and second volume. The 500k seems to control the bridge and mid/neck. What I want is the 500k volume to control the JB jr and the 250k volume to control the neck and middle pickup. The hot leads all seem to be wired fine and the grounds are wired fine also. The only part I am iffy about is the jumper from the 4th pole on hot side of the 5 way to the 1st on the tone side? I have never been any good with 5 way switches! Here's a schematic of the whole thing.

Snowdog

[ArtieToo]

Re: Whats wrong with this schematic?

I love a good puzzle. Let me chew on this awhile, and I'll get back to you.

Keep in mind however, you'll always have some degree of interaction in a dual-volume control guitar. It can't really be helped because you can't really build a "passive" mixer - which is what you're trying to do.

We can try to make it better, though. Let me redraw this to make it easier to follow, and I'll get back to you.

[ArtieToo]

Re: Whats wrong with this schematic?

Ok . . . one thing I notice real quick is, look at the terminals in cyan. Those should be the "common" terminals on the switch. I've highlighted in green the path that shows that each pup is connected to the wiper of the 500k in each pups switch position respectively. In addition, the middle and neck, are connected to the 250k at the same time, giving you an effective pot load of around 167k. (When the switch is the middle/neck switch position.)



I'm heading off to bed now, but I'll see what I can come up with in the morning.

[Fresh_Start]

Re: Whats wrong with this schematic?

That's not going to work the way you want with the two volume pots tied together like that.

Forgive me for starting with "20 questions":
Do you want a master tone pot?
Do you want the "5-way" to select pickups normally?
Do you want the 500k volume *only* in position 1 with the bridge alone, the 250k volume *only* in positions 3, 4 & 5, and both volumes in the circuit for position 2 with the bridge & middle pups on?
If you mean for both volumes to be in the circuit for position 2, do you want them to be independent (or do you want them to work like a "normal" LP circuit where the volumes are inter-dependent)? Hint - you've wired them to be independent here.
Does your drawing show the pots as if you were looking down on them (instead of looking at the bottom of the pickguard)?

Sorry - I thought that I had a solution for you, but it doesn't work after looking at it a second time. I can't figure out how to isolate the volume pots so that there aren't two paths to ground (one through each of the pots) all the time.

Hopefully Artie will be along shortly to help out. Meanwhile, answering at least some of my annoying questions will help others help you

Chip

P.S. I dug up this schematic from GuitarNuts, but *both* pots provide a path from hot to ground in all 5 positions. I think that would be "bad" in the sense of eating treble, but I could be wrong.

[idsnowdog]

Re: Whats wrong with this schematic?

I only want the 500k for the bridge. The JB jr with a 250k pot sounds crappy. I want the 250k pot for the middle and neck so the single coils don't sound shrill and clanky. One tone control is fine with me. The schematic although crude is a real life representation. The only part I am iffy about is the jumper from the 4th pole on hot side of the 5 way to the 1st on the tone side. I got that from the 3 pickup Tele schematic on the SD website.

Snowdog

[idsnowdog]

Re: Whats wrong with this schematic?

Dumped the 5 way switch and went with three mini toggles as usual. I should have done that to begin with. I hate 5 way switches!

Snowdog

[ArtieToo]

Re: Whats wrong with this schematic?

Dumped the 5 way switch and went with three mini toggles as usual. I should have done that to begin with. I hate 5 way switches!

Snowdog

Ok . . . that makes it simple to draw, just gotta wait til I get home from work.

[ArtieToo]

Re: Whats wrong with this schematic?

This should do it:



Hold down the SHIFT key, and click the image for the full-size version.

[idsnowdog]

Re: Whats wrong with this schematic?

Here's what the new one looks like. Its a pretty good compromise for guitars that have humbuckers in the bridge and single coils in the neck and mid. The volume controls are completely independant and the single coils aren't harsh like with a 500k pot and the humbucker isn't muffled and dull like with a 250k pot. The only thing you give up is one nearly useless tone control with a shared capacitor. Surprisingly the transition from single coils to humbucker sounds very natural and mixed they sound fine. All three postions are nearly the same volume and they don't sound compromised by either volume control. I am going to retrofit all of my guitars with this setup.

Just for the curious the guitar is a lefty Mexi strat bought for $99 at a pawn shop. Converted to right hand usage with Dimarzio Brian May pickups for neck and middle and a JB jr in the bridge. Cast string trees, carbon nut, fully shielded, etc.

Snowdog

[ArtieToo]

Re: Whats wrong with this schematic?

Yup . . . thats what I drew.

Just keep in mind, as you lower the volume, with this type setup, you lower the "load" on the pup, and thus, alter its sound characteristics a bit.

For instance, at half volume, the bridge "sees" a 250k control. At half volume, the middle/neck "see" a 125k control. Its a subtle difference, but there all the same.