Moog Lev96

[David Schwab]

The Moog guitar sustainer as well as the Fernandez and Floyd Rose and Sustainiac sustainers all have the ability to sustain a higher harmonic at the flip of a switch, not just the fundamental. The LEV96 has the ability to pick any of 8 different harmonics per string, presumably the lowest 8 harmonics (fundamental, 1 octave up, octave plus a fifth, 2 octaves, 2 octaves plus major third, 2 octaves plus major fifths, 2 octaves plus minor seventh, 3 octaves)....

How they do this I would suspect has to do with the phase of the signal fed back electromagnetically to the string... Altering the phase would shift the harmonic resonance. How they choose a specific harmonic is more puzzling; perhaps a specific degree of phase induces a specific overtone.... My guess is that a 180 degree phase shift in the feedback signal is what causes the moog guitar to do it's muted banjo sound, and perhaps a 90 degree shift causes an octave harmonic to resonate.

My other guess involves the fact that there are 4 circular sensor-thingys per string on the Lev96. Assuming that 1 of these is an input sensor (a pickup) and the other 3 are feedback drivers (inducing vibration in the string), then perhaps by altering the relative phases and/or intensities of the 3 different drivers they are able to induce specific harmonics to resonate.

just my guess!

They have multiple drivers per string. So they would be at different harmonic nodes.

[madzub]

I don't think the specific nodal locations of the drivers would necessarily have an effect, as the nodal locations change as you fret notes along the neck.

[David Schwab]

I don't think the specific nodal locations of the drivers would necessarily have an effect, as the nodal locations change as you fret notes along the neck.

That's true, but when you use something like an Ebow, you can get different harmonics be moving the thing around. So maybe saying nodes is not the right thing.

Maybe they are doing some sort of manipulation on the signal before they send it back to the strings.

[David King]

How do we know what we are hearing is all coming from the string? It seems to me they could just as easily be running some synthetic tones via a DSP right to the output.
Is it "musical"? I don't quite see the point myself unless you are a lazy guitarist who would prefer it if the guitar played half the notes on its own. You ought to be able to get similar effects via looping and harmonic emphasis in the signal chain via eq.

[David Schwab]

How do we know what we are hearing is all coming from the string? It seems to me they could just as easily be running some synthetic tones via a DSP right to the output.

Sounds like the strings to me. If you have ever played with sustainers or an Ebow those tones will sound familiar.

Is it "musical"? I don't quite see the point myself unless you are a lazy guitarist who would prefer it if the guitar played half the notes on its own. You ought to be able to get similar effects via looping and harmonic emphasis in the signal chain via eq.

OK so if doing it with looping etc., is good, why not this? I don't see how it's lazy. You can't get sounds like that otherwise. I think it can be very musical, unless you are a guitarist that only has a blues/rock vocabulary.

As an example, listen to the U2 song "With or Without You". That's very musical. The Edge is using an "Infinite Guitar" which was built by Michael Brook. It was the predecessor to the other sustainers on the market, but he only built a few.

[madzub]

Anything can have artistic (or musical) value in the right hands, so this is just a new thing that presents new possibilities. Loopers can be boring in the wrong hands, or brilliant in the right ones (see Owen Pallett aka Final Fantasy for a great example). Hey, great music was made before the electric guitar came around, so why don't we just throw them all away and go back to lutes and harpsichords.

[David King]

OK, good answers.