Ergonomic Semi-hollow Body Guitar — Cupid

I first fell in love with the sound of a semi-hollow body when listening to early Alex Lifeson recordings, in particular his beautiful ES-335 guitar tones throughout Hemispheres and Permanent Waves. Guitar solos in "La Villa Strangiato" or the (underrated) exit on "Different Strings" demonstrate the woody warmth (with bite) inherent in partially acoustic guitar construction.

Other semi-hollow body guitar players are well worth investigating: Steve Howe, B.B. King, John McLaughlin and Brian Setzer immediately come to mind.

But if you've ever played most semi-hollow guitars, "comfortable" is probably not your first adjective choice. Lightweight, but bulky and unbalanced. Rick Canton's work is one exception.

These issues are compounded for slightly framed people — Cupid (link provides more information) will be played by a 5'4" asian male, in this instance a plastic surgeon with small but nimble hands.

When Dr. Dominic approached me he was frustrated by difficulties in obtaining ANY instrument designed to comfortably fit his body. Let alone a semi-hollow body. Let alone state-of-the-art electronics. His passion for progressive jazz fusion was thwarted because he couldn't find an appropriate tool for self expression.

Together we've collaborated intensely to create a contemporary re-interpretation of the semi-hollow guitar concept, with some unique characteristics to meet his design specifics:

• Sculptural ergonomic body (asymmetrical design)
• Comfortable in right knee (seated), both knees (seated), or standing positions
• Acoustic sound chamber
• Trapezoidal Neck Profile (asymmetrical)
• Reduced scale with D extended bass E string
• Floyd Rose Graph Tech LB63 Ghost system

In particular combining the Floyd Rose with a sound chamber has proven highly challenging. These tremolo units remain unsurpassed in terms of tone and tuning stability, but require an extended — adjustable — inner-body spring assembly to balance string tension against the fulcrum knife edges.

By construction necessity, most semi-hollow body guitars employ the surface-mounted Bigsby tremolo, but those (classic) units are considered less desirable by guitarists who are serious about pitch bending.

To meet these unusual design requirements, I've had to develop three proprietary technical solutions:

• Asymmetrical acoustic chamber mounted to a solid body structure
• Cantilever neck attachment facilitating contiguous longitudinal string tension linkage with the Floyd Rose mounting posts
• Assembly which couples Floyd Rose spring unit — and subsequent secondary string vibrations — directly to the soundboard of the acoustic chamber

A few construction photos to help you visualize the design situation.

PHOTO: View from the back of the instrument where the neck assembly joins the solid body. Neck is curly maple and walnut with a titanium truss structure.

PHOTO: Asymmetrical body with Floyd Rose mounting structure. Cardboard template indicates future position of sound chamber.

PHOTO: Curly maple sides of sound chamber have been steam bent to shape. Here I've fitted and assembled the lower front corner joint using mahogany as a stabilizing block. Note the foaming action created by (waterproof) Gorilla glue.

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Comments

[05Ric]

Rick, this is very special! Very very exciting stuff!

[Rick Toone]

05Ric — I'm excited too. Thank you. Semi-hollow body instruments...

(note careful avoidance of the word "guitars")

...have excellent potential for capturing the individual expressiveness of a particular musician.

Their construction — via laws of physics — makes acoustic or semi-acoustic instruments inherently more responsive to touch. They respond faster and louder to input or play, because there is less mass to set into motion. If the pickup system is effective, the result will be tighter reciprocal interaction with the player.

Whoa. I need less coffee. Let's simplify:

a. less mass = faster response
b. faster response = more detailed sound
c. more detailed sound = greater expressiveness

I'm honored Dr. Dominic has asked me to take this leap forward with him.

[Rick Canton]

Total innovation and fantastic work Rick, looking forward to hearing the instrument. Does Dr. Dominic have any sound clips/videos to post here?

Best Regards,
Rick

[Ola Strandberg]

Congratulations once again - I can't wait to see the sound chamber coming on.

I agree with your sentiments regarding semi-acoustic instruments. This is the direction I am going as well. The opponents say that we do this at the expense of sustain... What are your thoughts on the subject?

Best regards,
Ola

[Rick Toone]

I think he's waiting on me. Once Cupid's done he'll be haunting YouTube.

(must sleep less...must work in shop more...must not accidently cut off hand)

Doh!

[Rick Toone]

Ola & Chris — thanks for checking in and asking the tough questions.

:)

This is all an experiment, of course, but the way I'm currently thinking about it is twofold:

a. From the *string's* perspective the instrument acts like a solid body guitar. The neck is coupled to the body and the body forms the Floyd Rose structure. So essentially the neck...body...Floyd Rose combination is one contiguous unit. This should give it solid body sustain.

b. What is unusual is the Floyd Rose spring assembly couples directly to the soundboard. Instead of losing those secondary string vibrations back into the solid body of the guitar — where they could phase cancel primary string vibrations — they are instead *amplified* and add to the acoustic volume and responsiveness of the instrument.

The only difference between theory and reality is that, in theory, there is no difference.

More reports as we progress.

[Rick Toone]

05Ric — I'll take a leap of faith with this one and assume your "rethink" is generally positive...

:)

[chris forshage]

Ooh I can't wait to see how this turns out! Really beautiful. I'm sure the trem will infinitely expand the expressiveness of the instrument.(mmm coffee) I do think Ola has a point regarding sustain. If a vibrating top is too light it will absorb all the energy from the string instead of giving some back(think banjo). But since there is a big massy floyd in the equation it should be ok. Can't wait.

[05Ric]

Have to say, seeing has made me rethink my next instrument ...

[05Ric]

...Very much so :)

[angelo]

i'm really impressed with your blog... very well made and all the contents are very informative...

[Rick Toone]

Angelo — thanks very much. We appreciate your feedback.