Hola
Pues no se si yo te puedo ayudar mucho. No he construido uno nunca, pero tengo uno y más o menos creo saber cómo funciona.
El ebow es básicamente un oscilador cuya señal de salida se conecta a una bobina. El campo magnético creado por la bobina es lo que pone a vibrar la cuerda.
El únic control que tiene es un conmutador de tres posiciones:apagado, vivbración "sin muchos armónicos" y vibración "con muchos armónicos".
Mi teoría es que el oscilador es un 555 que da una onda cuadrada. Fácilmente esta onda cuadrada se puede transformar en triangular: así tendrías los dos modos de vibración, con más armónicos y con menos.
Ya te digo, es una teoría, pero creoque por ahí van los tiros.
^_^V
Parece que es un poco más complicado de lo que creía:
I already have an ebow, and I like it. I'm not saying the schematic itself is brilliant, but the idea behind it is. I'll try to summarize. The triangle in the middle is an "operational amplifier", which is capable of doing a lot of stuff, but in general you can think of it as amplifying the input signal. The input in this case seems to come from the telephone pickup. The output is a transformer, which is something like a guitar pickup to begin with.
Electric guitars work because you have a ferrous metal (the strings) moving through an electromagnetic field (generated by the pickups) which induces a current in the pickups. You can do the reverse (make the strings move) by running current through the pickups. So, the ebow seems to be taking input from the strings, amplifying it, and inducing the strings to move with the amplified signal. It's feeding the output of the strings back to themselves which tends to reinforce whatever they were doing (although often in somewhat mystifying ways).
A magnet glued to the end of a vibrator would be useless, because it always vibrates at the same frequency. The reason the ebow works is because it creates vibrations that match what the strings are already doing, so the frequency will be right to get reinforcing feedback.
Ojo a esto. Qué buena idea!:-----------------------------------------
Something I've tried a few times which can be pretty interesting (sorry for the derail but it reminds me of it).
Take a guitar, and split the signal. Have one of the signals going to another room where you have an amp set up to a cleanish tone, and you're miking the amp. Have the other signal go into the room with you, with a heavily distorted, fairly loud amp. Have this amp close to where you're playing guitar. By turning into the amp (facing it), you can get a LOT of feedback. But you're recording off the clean amp... so you get this incredible singing quality out of it. Hard to explain, I'll have to see if I can dredge up a sample. I don't perform live but I always wondered if I could do the same thing by having the distorted amp going to a very small speaker that I could hold in my hand or have on a mic stand or something, and just bring it close to the guitar when I wanted the effect.
^_^V
o mas facil para mi..... sabe alguien donde puedo comprar uno?
No lo encuentro por ningun lado....
Seria cuestion de jugar con un generador de señales.. Vamos. No puede ser tan dificil...
. Interesante .... muy interesante.
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