Fernandes Sustainer/Infinite Guitar

[TriggerX]

When I first found the internet I was frantically trying to get schems for a Fernandes Sustainer unit. Therer is some further info here...

http://www.fernandesguitars.com/menu.htm

I had one of my own and was transplanting it from one guitar to another. It looks incredibly simple, 3 or so IC's and 4 or 5 transistors. I found loads of info about origins, how great it is etc. but no tech data. So I guess my question is (predictably... :roll: ) Anyone got a schem or know where to get one?

 

[pucho812]

sounds like an e-bow type device.

The EBow does its work on the string itself by producing an energy field that vibrates and sustains your guitar string...

Welcome to the world of Direct String Synthesis?. The principal is simple: a focused feedback loop directed at a single string. This produces a powerful, infinite sustain, rich in harmonics for incredible guitar sounds. It's like amplifier feedback with greater control and predictability, at any volume, even through headphones. This hand-held synthesizer provides an amazing variety of textures and tonal slurs ? virtually an instrument in itself!

 

[ciminosound]

Hamer used to have a device like this too, before Fernandes. May be the same thing...

 

[PRR]

On page http://www.fernandesguitars.com/sustainer.htm under "How it works" there is a clear picture.

No magic. Hold an amplified guitar too close to its amplifier, and it will feed back. With care, it feeds back best at the pitch the string is tuned to, though harmonics are possible too.

Feedback through 100 watt amps and the acoustic in-sensitivity of a solid guitar is very inefficient (and loud). Better to shake the string directly. Put another guitar pickup under the string. Amplify the main pickup and use that to drive the second pickup. Adjust gain and phase until it feeds back. The feedback will rise in level until something stops it: string flies off the bridge, amplifier runs out of power, or possibly an AGC system.

I've done something like that with a tuning fork. It took a surprising amount of power and coupling to get it to work. That these guys have done it with a 9V battery is impressive. With their clues, I'd use like an LM386 low-volt speaker amp chip plus a preamp chip for buffer and a little more gain. I'd try re-winding a very hot pickup with a few turns of fat wire so it came out about 20 ohms, and mount that where they mount their second pickup. It is possible that a standard pickup frame does not have the magnet strength and coil-size needed to drive a string well.

 

[EZ81]

Somewhere i have a e-bow schematic and IIRC it looks exactly as PRR wrote, a pickup in front of a LM386 which is driving a low impedance coil. I'll se if i can dig it out later...
;Matthias

 

[EZ81]

Found it and redraw it for copyright reasons... :

No idea if it is correct..

 

[mike_relay]

Ok.. this topic made me go out and buy an E-Bow... But I's like to build something similar that would work better for my bass...
I'm a little confused by the schematic.. what are the two coils?

Thanks,
Mike

 

[Mendelt]

The first coil is the pickup in the ebow. This signal is then amplified and the other coil will create a magnetic field to feed back the signal to the strings.

How does it work on bass? I have been thinking about buying one of these too.. But there's nowhere i can try one out

 

[mike_relay]

I haven't had that much luck with it on my bass.. It worked better on my upright.. but I already have a bow for that.. :wink:
My favorite thus far has been on my grilfriend's acoustic. She's got really light strings on there, and it works really well. I might try to get some very light strings for my bass and try it again.

Does anyone know what the eBow uses for a pickup? Is it something I could buy or would I have to make my own? (which would be better if it's fairly simple)

 

[mike_relay]

I was looking at patents at www.uspto.gov.
The ebow is patent 4075921.
In the patent they specify the coils have ALNICO-5 magnets in the coils.

Also, if you do a search for "ebow" you can find a couple of patents of similar inventions, some that are similar to the Fernandez sustainer.

-mike

 

[TriggerX]

The delay in replying is regretted. I am very grateful for all the feedback people. I hope to have a decent place to live soon and hopefully, with that, I can get a bench happening and build the sucker. Thanks again y'all.