Carvin and the five-way switch

No, it’s not a scam involving a ball and cups.

Quite a few years ago I had a local shop install a DiMarzio ToneZone pickup in my Carvin guitar with the hopes that it would make it sound more like my Ibanez. It did not.

A few years after that I picked up a fairly recent year Gibson SG. By fairly recent I mean that I wouldn’t feel bad about modifying it. The better, older guitars that I had in the past were kept in factory-fresh condition out of the fear that any change would lower their collectibility. You can probably see where this is heading since this was not one of those.

One of my planned project for the last 2 years (hey, I have a lot of projects on my list!) has been to move that DiMarzio pickup into my SG. At the same time, I would add coil-splitting controls, and maybe a phase-reversing switch.

It turned out that SGs are thin. I knew that, but never imagined that putting standard push-pull pots in one is not an option. I didn’t want to start drilling holes to add switches. The plan was downsized.

I thought that perhaps I should just move the DiMarzio and skip the other mods. That was when I first noticed the changes that were made by the store when they installed the pickup. They made the pickup’s mounting hole bigger one one side, and added a new hole on the other side. I suspected that the old pickup would no longer fit because its mounting screws were smaller.

Fine. Leave the pickup in the Carvin. I’ll just have to buy new pickups if I want to improve the SG. Downsized again.

Carvin’ up the Carvin

Although it plays very well, I didn’t plug in the Carvin very often because of its sound. But now that I had decided not to remove the pickup, I plugged it in to see if I could dial in a sound that I liked. I liked the sound on the one new pickup, but the others were dead sounding and the controls had very little effect.

Before I make a hardware change, I read. And research, and read. It’s a lot easier than doing and undoing changes by trial and error. Certainly someone before me had tried to solve the problem of muddy tone. One of the things frequently discussed was “fifties-style” pickup wiring. I thought that maybe making that minor change would help.

My soldering iron hadn’t been used in a long time, so it was time to burn off whatever dust had collected on it. While it’s open I could make a change that had been on my mind for a long time: reverse the center pickup to get that cool out of phase sound! (In case you don’t finish this article, don’t do that mod. At least not if you don’t have separate volume controls for each pickup.)

The Carvin is not a collectable guitar. It is sort of a Strat knock-off style, with one humbucking pickup at the bridge. It also has a toggle switch whose purposes eluded me at that time. Whatever it did, its effect was very subtle. It was a home-built guitar, made from a kit by someone I used to work with. They had some sort of an electronics and guitar-tech background, so I wasn’t worried about its insides when I bought it used. Oops.

I opened it up and was puzzled by the 5-way switch. The wiring didn’t make sense to me, so it was time to see if there was a standard for the switches — insert brief Google research interlude here — and there was. Here is the important part about 3- and 5-way switches:

I was no longer puzzled. I now knew one of the reasons the guitar sounded so limited and dead: It was wired wrong.

I fixed the switch wiring and changed the tone pot’s connection to “50s style”. (Sidebar: I also reversed the phase on the center pickup, but had to take the guitar apart again to put it back to normal because it sounded horrible — not a bit like I thought it would.)

I also added a new connection because I now knew how the switches worked.

Two new sounds

When I was done, one half of the 5-way switch worked like normal. In this type of standard wiring the other half is normally unused, which made it available to me.

This guitar also had that extra mystery switch. What that did was change the humbucker coils from a standard series connection to a parallel connection. It makes a subtle tone difference. However, it also gave me the possibility of accessing its center tap in a switched manner.

With my addition, when the neck pickup was selected using the 5-way I could use the series/parallel switch also put one coil of the bridge’s humbucker in parallel with the single-coil neck pickup. It also meant that there was a position where all 3 pickups could be selected. Nice.

It’s described in more detail in part three of my two part series on guitar wiring basics.