On Changing the Personality of a Guitar – Part 1

© 2016 Don Baker dba android originals LC

 What makes up the personality of a guitar?  The way it looks?  Sounds?  Feels?  And why would anyone want to change it?  Well, people change all the time, and even it they don’t, what musician who can hasn’t spend a bundle of money trying to find the perfect guitar for a particular style of music or kind of gig.

In this study, we’re going to look at one way to change the tonality and range of tonality, either radically or subtly, of an electronic stringed instrument, particularly guitars.  First, let’s take a look at Fig. 30 of a patent application, U.S. 2016/0027422 A1, filed July 23, 2014.  In brief, it shows a plug-in cross-connection board that connects (4) plug-in pickups to a tone switch.  An undisclosed Provsional Patent Application, filed June 28, 2016, covers an arrangement that allows commonly available switches to be used with any number of pickups.  Those patent applications and copyright law protect the intellectual property presented here.

First, here is the drawing, followed by an excerpt from the patent explaining it.  Feel free to skim both and skip down to the rest of the discussion.

Page 26 Fig 30

Excerpt starts

[0140] Fig. 30 shows a more flexible embodiment than making all the connections in Figs. 23-27 directly on the switches and their terminals. N-up pickups A (363) and D (369) and S-up pickups B (365) and C (367) each have wires ending in female connectors (371), which plug into male pin or header connectors (375). These connectors can be either keyed (polarized) or unkeyed. Unkeyed connectors can be reversed in the event of a pickup wiring error. The connectors allow other arrangements of the pickups between the neck and bridge (or tailpiece), such as N-N-S-S or N-S-N-S, or vice versa, to accommodate other musical theories and settings.

[0141] The male pins (375) are connected to a 6P6T switch (375), as in Figs. 24 & 25.  The six wires for each switch position are connected to a female circuit board connector (381), into which a circuit board (377) plugs with board-edge finger contacts (379). The board has vertical wires (389) on one side for the switch terminals, and horizontal wires on the other side, consisting of a common output wire (383), a common ground wire (385) and several interconnect wires (387) that are separate for each switch position.

[0142] Open circles (391) designate cross points where the horizontal and vertical wires do not connect. Filled circles (393) represent cross points with connections between the horizontal and vertical wires. If the open circles represent holes through the board, this can be as simple as a jumper wire soldered from one side to the other. Here, the connections for A+C (395), -B||C (397) and (A+C)||(B+D) (399) show at three of the switch positions.  Otherwise, the same thing can be done with commonly available analog and/or digital semiconductor crosspoint arrays, and a microcomputer driver. In this case, only two of the interconnect wires (387) are necessary, requiring interconnections between 6+4 or 10 wires. So theoretically, 10×10 or 16×16 integrated circuit crosspoint switch matrix could accomplish the same thing as the 6P6T or 6P12T switch (375) and the matrix board (377) combined, to produce all 12 serial and parallel humbucking combinations. Thus the embodiments are not limited to the physical features of Fig. 30.

Excerpt ends

Note that Fig. 30 shows at least one of the pickup combinations to be a humbucking quad, along with the humbucking pairs, which can be in-phase or contra-phase (depending on the pickups used) and serial- or parallel-connected.  The black dots on the cross-connections board represent connections; the open circles do not.

The Notes on Humbucking Pair Placement show three ratios of opposite poles produce different ratios of in-phase and contra-phase HB pairs for 4 matched pickups.  One can choose a set of pickups with an equal number of opposite poles, which provides the maximum number of in-phase HB pairs, and match them with a cross-connection board that provides the warmest tones.  Or one can choose as set of pickups with all the same poles up, which produces only contra-phase HB pairs, and match them with a cross-connection board that maximizes bright tones.  Or one can do anything in between, say to maximize the range of tones from warm to bright.

Further, the placement and spacing of poles has an effect on tone.  Consider the general principles of humbucking pairs (all other things being equal):

  1. Pairs closer to the bridge are brighter than those closer to the neck
  2. Pairs with coils closer together are brighter than those with coils farther apart
  3. Parallel-connected pairs are weaker and brighter than series-connected pairs
  4. Counter-phase (out-of-phase) pairs are brighter and weaker than in-phase pairs
  5. Rules 1-4 can interfere with each other
  6. You can only put so many pickups between the neck and the bridge, and the more you have, the smaller the tonal differences in adjacent pairs with the same connections.

Note the discussions on simply changing the position of the odd pole in a 3-coil guitar between: An All-Humbucking 5-Way Superswitch Circuit  and  HB Supersw Circuit for 3 P/U w/ Odd Pole at Neck.

Say the guitar has plug-in spaces for five matched single-coil pickups.  That means 20 different choices of HB pairs, plus a number of HB quads.  Since both the cross-connection board and the pickups can be replaced by different plug-in boards and plug-in pickups, this approach provides a very wide array of choices, even if the tone switch has only 5 or 6 positions for humbucking pairs and quads.

Using this approach, a favorite guitar or bass, which has just the right look and feel, can be changed in tonality all the way from jazz to folk to country to rock to metal.  Maybe even on the same tone switch.

When will this be available in a store near you?  When can you change the personality of your guitar with a plug-in module and plug-in pickups?  Good question.  When approached about licensing this kind of technology, most if not all established guitar companies beg off, claiming that they have too many projects going already.  After all, musicians are not currently asking them for it, and no one is yet taking a slice out of their sales with it.

Besides which, most sales are bound up in the traditional look, sound and feel established by the gods and legends in music.  You want to be noticed?  You want to be great?  Then buy the look, sound and feel that made your heros great, they sell us.  Never mind that those same heros became so by following their own visions, and developing their own unique sounds, borrowing from their own heros, not aping them.

The object of this site – to show you that you have a much wider choice of sounds than you may have thought – if you can either build it for yourself, or convince the guitar companies to provide the means to do so.

Legal Notice – Copyright and patent law (Patent Pending US 2016/0027422 A1, filed July23, 2014; an undisclosed U.S. Provisional Patent Application, filed June 28, 2016) protection covers the material you see and read here.  Here’s how to avoid getting sued:

  1. Build it with your own hands for your own personal use, at your own risk
  2. Do not sell it or make it for sale
  3. Do not take any money to do it for someone else
  4. Do not reproduce it for any and all public distribution
  5. Provide only links to this site with personal descriptions of how it worked for you
  6. Do not try to profit from it in any manner, shape or form