Monday, February 13, 2012

History and Funk part 2 - the funk

I promised stories. They will come as the months roll along. I also promised to teach. I’m not saying that I have arrived at guitar guru status. Actually I learn something new with each project it seems.  That is what excites me. I cant help but share. Lets get to it then.

 This one belongs to a buddy of mine, Dave Macha, who plays in a local funk band called Champagne Room. A fender Toronado.  Its two humbuckers give a good fat punchy tone, great for a rhythm player. Dave also wanted the option of having the crisp clean sounds of single  coil pickups. A “coil tap” would give him this option. All we have to do is drill a hole in his guitar and add at switch. He wasn’t going for that. No more holes!
     Ah… I love a challenge!
 We talked about options and decided to “tap” both pickups and wire them parallel to each other, giving them that clunky “out of phase” sound. All I need to do is figure a way to do all this with out adding a switch. Now were getting funky!
 The guitar already has one three way switch ( pickup selector ) and four knobs ( two volume and two tone controls ). Before he left Dave told me he only wanted one volume and one tone control, leaving the other two open for our coil taps.
 With that Dave was off to play his New Years Eve gig and I was ready to dive in!

     The first challenge was to find the color code Fender used for the five wires connected to each pickup. Each pickup manufacture uses its own code to tell you what wire goes to hot, ground, etc. a quick search on line will provide lots of info. I prefer instead to open things up and see for my self. A peek at the under side of one of the pickups reveals red, green, black and white wires. Plus the silver ground wire. I then used a multi-meter to determine which were the start and finish wires of both the north and south coils on each humbucker. ( Donald Brosnac’s book, Guitar Electronics for Musicians explains this process in the Hardware Components Design and Function chapter. ) In this case red is the north start ( hot ) and black is the finish. Green then is the south start ( ground ) and white the finish. In most humbuckers the two finish wires are soldered together ( in series ) making the two coils one. In our case were going to wire the pickups so that we can have both coils active ( humbucker ) or just one ( single coil ). Normally a switch would be used to accomplish this but were going to use a pot!

   If you think about it, a pot is just a switch that you can fade in or out. So why cant we use it to split the coils in these pickups?  If I were using a normal switch for the coil tap, it would work as follows.  The on ( or full humbucker ) position would leave the two finish ends of  wire connected, giving us the power of a series humbucker. Flip the switch to the “cut” position and it sends both the finish ends to ground. The finish wire of the south magnet will give us nothing because the start end is also already connected to ground. The finish end of the north magnet, however, will give us a whole new connection. Remember, we used the north magnet start wire as our hot. If we now use the south end of that wire as our ground… we have a single coil pickup!
 A pot is just a switch with resistance that can be adjusted or “faded” remember? Any given pot will have lugs for in, out and ground. As the knob is turned signal traveling through gets either closer to or farther from ground. ( when you turn your guitars volume knob all the way down, that guitars signal is going straight to ground. ) apply this info to what we already know about a coil tap and magic happens. I connected each of the pickups finish wires to the middle lugs of the two unused pots (Eric Coleman recently covered a similar mod in the Trade Secrets news letter) and made sure the pots were grounded. With the pot full on, the two finish wires of our pickup have no where to go and are left together in the beautiful bliss of series hum bucking. As we role the pot back more and more signal escapes to ground until we have a single coil. Like I said, magic. 

  All that’s left to do is plug it in a test my work. I used a Fender Mustang III for a test amp. Success! The Toronado sounded super funky with both pickups cut to single coils. As I hit the first chord I could almost here James Brown scream “Hit Me!” Because the coil “taps” are actually pots and not switches Dave will be able to blend the coils for limitless tonal possibilities. 
                                         Dave was happy. Good enough for me.