Sustainer Ideas

[mrjstudios]

Well, my fetzer / ruby works now -- with a speaker and with the sustainer!

The soldering job is pretty crappy since I did it, so it cuts in and out every once in a while, but I'm not worried since it does WORK the rest of the time.

Note: the F / R is completely stock, except the gain pins (1 and 8) on the 386 are wired together. Leaving the other 2 pots in the schematic seem to give you enough control over the system, so eliminating the 386 gain pot saves money and more holes in your guitar....

Here is the driver right after it dried out -- ignore the hot glue on top, that was just to help keep it together while drying.

Also TO ALL THAT USE ELMERS GLUE OR ELMERS WOOD GLUE TO POT THE DRIVER: LET IT DRY AT LEAST 4 DAYS BEFORE USING IT!!!

2 days after I took the hot glue off, in the center it was still wet, but after 4 days it all was solid.

[Truth_David]

Sorry Dave, been really distracted and hardly able to fully read all this and take it in, let alone participate as I normally would...lot going on...

My apologies too, I found myself getting really frustrated

Yes, col has a similar thing with his 4 position rotary, but he has only one pickup. I was not able to have time, at the time, to really study the micro switch idea, but I didn't see how it would work for the bpassing and all. I found that I needed 4pdt to achieve all this, and at least all the grounds would still be connected thropugh the selector with this soulution.

Well, I don't pretend to comprehend it fully myself either, but perhaps with his explanation it will make sense, but briefly, as far as I recall, once the micro switch is tripped the sustainer is connected directly to the bridge p/up and nothing else is connected.

It is one I used in a variation myself with the sensitivity pot on the tailpiece box idea. This idea was to use two microswitches behind the pot, as you pushed back on the palm of the hand or manipulated the pot, the switches would activate the system momentarily for touches of feedback here and there. Unfortunately two were not enough and the whole wiring into the guitar impractical, it did work (a bit of neoprene mouse pad as a washer to act as a spring worked really well) and maybe a useful idea for some other aplication some time (kill switch pot maybe)...

I already have a pair of momentary mini switches mounted as the midi selector part of the RMC system. They are mounted right next to the megaswitch E, so perhaps they could be made to do the job of Juán's micro switch?

As I say though, I didn't really study it at the time, and the post flew by, perhaps you could find it and bring it back to the present...

P172, post 1569 - 1570

As for a collaboration, more than willing, but at present I have not the time to do anything in the way of experimenting in a practical sense, but I am getting closer. The translating does make it difficult, obviously, and Jaun has posted some interesting stuff and obviously taken ideas like sheilding that little bit further than I was able to achieve...

Juán's problem is time, as he is trying to hold down several jobs at once, and still fit in the time to build his own guitar from scratch and work on the sustainer project too....personally I don't know how he does it, although admittedly things are going pretty slowly. But perhaps one approach would be for you to frame specific questions or suggest project themes for Juán to concentrate on, I could then translate whenever required and chase him up about any specifics you needed urgently. He tends to have a typical boffin's approach of putting to use anything he happens to have around. In his case that is plenty of old radios, TVs, computers and stuff like that. He has access to far more resources than I do, which makes it a better idea that he puts the stuff together then sends it to me when it is in a more practical stage of development. He also has a great deal of experience in terms of building and working with valve (tube) equipment, and is quite capable of building valve amps for example from scratch. So what I was really saying is that we should show him that he is valued and direct questions or problems in his direction. This is only my suggestion, and I daresay that being the humble guy that he is, he would not be very happy about me saying this stuff, but that is my way...

I like the microswitch idea, and position 4 on my new guitar is really not much use (humbucker bridge and middle pickup) having a weird tone, so sacrificing this for a sustainer selection would be attractive proposition. It is however I suspect problematic with a standard selector, would probably require a super switch and some kind of push pull pot for the harmonic mode.

Juán has opted as I mentioned, for a rotary switch for the harmonic modes and sustainer on/off, leaving the micro switch to do the switching simultaneously with the pickup selection. That thus simplifies things quite a bit, requiring only a sensitivity pot apart from that.

When you have a look at the pic Juán sent, you will see that it involves glueing the micro switch to the selector switch itself inside the switch mechanics.

The idea I was referring to for fitting the micro switch into a space in between the selector lever and the slot in the pickguard was something entirely different, my own idea, and probably not such a good one, for the reasons already mentioned previously.

So, got to run again, but appologies for not picking up on everything...very distracted... pete

Not to worry, really I was pointing it out because I felt that it was to your detriment, because as the thread continues to grow, any ideas that go un-noticed by you will tend to get buried and be subsequently difficult to dig out later on, unless anyone specifically remembers when they were posted, as in this case....

My thoughts and best wishes still with you.

David

[Redhat]

Hi there, been reading this post for a bit, and finally decided to post. Must say, took a few weeks to get through the whole thing, and I've been really impressed with what everyone has done. I've been a semi pro guitarist for almost 20 years now, and started thinking about sustainers (didn't even know the term at first) when I decided to record all my guitars direct on my newest album. I wanted a big live sound, but wanted to be able to record at low volumes while the family slept.

What I came up with was simple. I gutted a cheap 5 watt practice amp, chopped up the speaker so it made as little sound as possible, but kept vibrating, spliced it to a mic cable, and screwed it to a $2 hand clamp from wall mart. Feeding the remains of the practice amp a signal from my board, I was able to affix the clamp to different areas of the guitar (body and headstock) with a simple squeeze to get different fundamentals or harmonics. This worked fantastically to get the sound I was after without standing in front of my Marshall Anniversary (best amp ever IMHO) and buggering with angles.

My buddies were uber impressed and suggested I should patent the idea, but my hopes were dashed when I saw Sustainiac already had . Oh well. Still the handiest studio guitar tracking accessory I've ever used, and no mods to any of my guitars, and it works with all my pickups on all strings. It's ugly as sin, but I may look at adding a ruby style amp and cell phone vibrator inside the clamp with a 1/4" jack on the thing so I can pack it around a little easier to other studios.

Anyhow, here's what I'm thinking now, and wondering what you all think of the idea. Please excuse how I try and explain it. I'm going to create a 4 channel bobbin, with the channels running top to bottom instead of side to side. The 2 channels in the middle will be 3mm wide each, for 2 magnetic driver coils wired out of phase with one another. The 2 outer coils will be wider and again wired out of phase with each other to act as an actual humbucking pickup. The pole pieces for the 2 driver coils will be 2mm blades on the outside of the inner coils, while the humbucking poles will be height adjustable screws on the outside edge of the 2 outer coils. I'd make 2 such pickups/drivers, one with a hotter driver then the other, and use a standard singlecoil between them.

I was then thinking of using one of the big 4 by 5 switches Stew Mac sells so that, when an auxiliary driver power switch was turned on, I'd have the option of using either humbucker on its own, or either with the opposite driver turned on, or the middle pickup with the driver turned off on both numbuckers.

So, any opinions of the plan? I don't see why it wouldn't work, but you all seem to have a lot more experience than I with the magnetic sustainer concept, so thought I'd put it by you all before I go ahead with it.

Thanks by the way fo any responses.

Cheers,

Daryl

Edited April 13, 2007 by Redhat

[Smile44]

It's ugly as sin, but I may look at adding a ruby style amp and cell phone vibrator inside the clamp with a 1/4" jack on the thing so I can pack it around a little easier to other studios.

This idea is very interesting, but are you sure it would work using a cell phone vibrator ? You can't control the frequency at which this vibrator...well...vibrates ! What would be the use of a ruby there ? To obtain sustain with this system, the vibration should be as the same frequency as the original signal ?

Cheers.

Smile44

[Redhat]

Ok,

I had another idea that I'd like to implement. What about using a Neutrik combo jack in the guitar? If the sustainer was powered by a rechargeable battery, then an external box could be setup with a charger, XLR in, and 1/4" out. The idea would be to use an XLR cable when practicing at home into the charger box, then to your practice amp (pod, di, etc) so that the battery could recharge. When you were at a gig or studio, you could just use a regular guitar cable as usual. Thoughts?

[Redhat]

With regards to the use of a cell phone vibration motor, the are essentially the same principle as a speaker. The difference is in how the physical motion takes place. In a speaker, a sleave moves up and down over the coil. In a vibration motor, the physical motion is rotational, with a weight on the end of the spindle to create the vibrations. I would expect the frequency of the vibrations in a vibration motor, as with a regular speaker, to mirror the current supplied. Cell phones vibrate at a single frequency because they are only supplied with fixed frequency current. I think....

[psw]

With regards to the use of a cell phone vibration motor, the are essentially the same principle as a speaker. The difference is in how the physical motion takes place.

Quite right, and this is something I did a little experimenting with. I also did things with speakers and physical vibrations of the instrument and it does work to a degree, but you do need a few watts, the magnetic sustainer needs only a half watt of battery power and cirtainly looks neater and performs more predictably. As for motors, you can see the effect if you take an ordianary motor and hook it up to the F/R amp which provides a electrical A/C signal in sync with the vibration of the strings. Problem is in part inertia. You will see the motor try and spin backwards and forwards, but it has to stop the travel in one direction physically and at high frequencies this is not possible to overcome.

In an analogous way, our electromagnetic device has to reverse the flow of it's current and it's magnetic energy, while much faster, it still suffers some lag (for which some compensation circuits have been devised). In my DIY model, the thin driver seeks to counter these effects with an efficient coil that is fast enough over the range of audio frequencies for this project. Hence, a coil with flaws (inner vibrations, etc) may not be able to react fast enough and fall out of sync with the physical vibrations of the strings...especially the high strings.

The idea would be to use an XLR cable when practicing at home into the charger box, then to your practice amp (pod, di, etc) so that the battery could recharge. When you were at a gig or studio, you could just use a regular guitar cable as usual. Thoughts?

I have used my guitar with recargable batteries perfectly well. I had two so one would recharge while I used the other. They have a slightly lower voltage (8.4V) and don't last as long, but are perfectly servicable. We have discussed this a bit, a stereo cable could be used for remote power or recharging purposes (as with the X-Bat device) it would seem and could be a neater solution to an XLR. Otherwise, a discrete power jack on the control cavity would work, just plug the guitar into the charger occasionally.

Hi there, been reading this post for a bit, and finally decided to post. Must say, took a few weeks to get through the whole thing, and I've been really impressed with what everyone has done. I've been a semi pro guitarist for almost 20 years now, and started thinking about sustainers (didn't even know the term at first) when I decided to record all my guitars direct on my newest album. I wanted a big live sound, but wanted to be able to record at low volumes while the family slept.

This is exactly the beauty of this device, the ability to get that "live", "loud" sound with control and little to no acoustic volume. The predictability of the sustain is another big plus as far as the creative use of feedback is concerned, once you get used to the response, you know the sustain or the harmonic feedback will be there for your take...

Anyhow, here's what I'm thinking now, and wondering what you all think of the idea. Please excuse how I try and explain it. I'm going to create a 4 channel bobbin, with the channels running top to bottom instead of side to side. The 2 channels in the middle will be 3mm wide each, for 2 magnetic driver coils wired out of phase with one another. The 2 outer coils will be wider and again wired out of phase with each other to act as an actual humbucking pickup. The pole pieces for the 2 driver coils will be 2mm blades on the outside of the inner coils, while the humbucking poles will be height adjustable screws on the outside edge of the 2 outer coils. I'd make 2 such pickups/drivers, one with a hotter driver then the other, and use a standard singlecoil between them.

I might need a diagram to get the feel for this idea, but it sounds as if you are seeking to retain the pickup selection which may not be possible, even with multi drivers. We are exploring the idea of a mid pickup driver, but a very efficient EMI reduction desigh would need to be devised. Even then, squeezing it between two humbuckers may be a little optimistic, especially on a 24 fret guitar... Even with effective dual drivers, your combined pickup selection would need to be disabled as you couldn't have both pickups and both drivers on at the same time, could you!

Anyway, some interesting thoughts and ideas all the same... Welcome to all you guys... pete

[zfrittz6]

Hola, a todos.

Tengo grandes noticias para el sustain infinito DIY, pues he conseguido una bobina ó conductor que trabaja perfectamente en la posicion media de la guitarra sin blindaje, gracias a la poca energia que consume el cual he realizado basandome en las pastillas humbuckers y a una idea de un post pasado el cual pasa casi inadvertido y no recuerdo quien lo escribio, ese post hacia referencia a una bobina doble de 16 ohmios cada una conectadas en paralelo, asi que me decidi ha hacer varias y conectarlas en paralelo, ayudandome de un folio lleno de polvo de hierro y comprobando como se magnetizaba éste y hasta donde llega la EMI, resultando que para una misma potencia del amplificador unas emitian mas EMI que otras despues de esto he llegado ha la conclusion de que las bobinas que mejor funcionan y mejor concentran el electromagnetismo han resultado ser de 13,5 ohmios o lo que es lo mismo 205 vueltas de hilo de 0,2 mm. enrrolladas en una hoja de segueta de 5,6 cm. de larga por 7 mm. de ancha y un grosor de 1mm. la cual es de acero y buen conductor del magnetismo con unas hendiduras a los lados en las cuales se enrrolla el hilo, para que se entienda pongo un dibujo que lo aclara mejor.

una cosa que se me olvidaba cuando este hecha se enfundan las bobinas con papel de cobre para evitar cualquier interferencia de alta frecuencia, es decir como los conductores de sustainiac que estan envueltos en una lamina de cobre y de camino se protege la bobina.

Saludos.

Edited April 14, 2007 by zfrittz6

[col]

Hola, a todos.

Tengo grandes noticias para el sustain infinito DIY, pues he conseguido una bobina ó conductor que trabaja perfectamente en la posicion media de la guitarra sin blindaje, ...

Thats great news Juán...

(noticias muy buenas Juán. gracias por trabajar en esa idea )

To translate (badld... roughly sumarising a google translation)

Juán decided to try the idea I posted of using two 16ohm coils in parallel (instead of 2 x 4ohm in series), he made a few different versions and came up with some good overall settings... "...I have arrived is the conclusion that the coils which better they work and better concentrate electromagnetism have turned out to be from 13.5 ohms or what is the same 205 thread returns of 0.2 mm enrrolladas in a leaf of segueta of 5.6 cm. of long by 7 mm of wide and a thickness of 1mm. which is of steel and good conductor of the magnetism with cracks to the sides in which enrrolla the thread, so that it is understood I put a drawing that clarifies it better..."

He says that this setup works well in the mid position ! :-D

great news, and I hope someone else can also test this driver configuration out

Col

Edited April 14, 2007 by col

[psw]

That's great, very much the approach I was considering with a "rail" style HB (intended to build on top of spazzy's donated rail pickup), keeping the blades close to keep the EMI in check. Good to see it doesn't require all that magnetic shielding that could be hard to construct.

I wonder if the bulk of larger coils in parrallel are important to it's success. I see that the coils retain the thin 3mm depth of the prototypes but wonder how you get that much windings on and still keep the coils close, but, I imagine with a 1mm core that a bit of space is saved.

Great stuff, it would be good to hear it and it is a shame about the difficulties in translation but it is amazing that jaun can make head nor tale of what the rest of us are on about... well done, juan... pete

[col]

One question Juán, did you try different wire guages ?

(¿Una pregunta Juán, intentaste diversas medidas del alambre?)

Col

[Truth_David]

Hi all,sorry I got onto this so late, just got back from our church worship service (another one in the morning so can't spend long....)Hi everyone, I have great news for the DIY infinite sustainer! I have managed to get a single conductor coil to work perfectly in

the middle position of the guitar without screening, thanks to the small amount of energy that is consumed, I managed it on the basis of humbucking pickups and the idea in a previous post which went almost un-noticed, and I don't remember who wrote it, but this post made reference to a dual 16 Ohm coil, each of which is connected in parallel. So I decided to make a few and connect them in parallel, with the help of a folder full of iron filings in order to see the magnetic field and how far the EMI would reach. The result was that with the same amount of amplification, some emitted more EMI than others. Following this I reached the conclusion that the coils which work best and concentrate the electromagnetic properties best are those of 13.5 Ohms or 205 turns of winding of 0.2mm. These are coiled in a leaf of metal 5.6 cm long by 7mm wide and a depth of 1mm. This is made of steel and is a good magnetic conductor, with a few fissures on the sides into which the wire is wound. I have included a diagram in order to help understand better and clarify this more.

One thing I forgot - once finished, wrap the coils in copper foil in order to avoid any HF interference, in the same way as the Sustainiac conductors are screened, wrapped in a copper laminate which also serves to protect the coil.

Cheers

I hope this is easier to understand than the Google translation

David

Well done Juán, I knew you would crack it!!!

Edited April 14, 2007 by Truth_David

[Truth_David]

One question Juán, did you try different wire guages ?

(¿Una pregunta Juán, intentaste diversas medidas del alambre?)

Col

Hi Col, just so Juán understands, the word is 'hilo'

Juán, estoy seguro que te hayas enterrado de lo que quisiera preguntar Col, pero para ser seguro, esto es la pregunta (eres un maestro tio ):

Juán, tengo una pregunta, ¿has comprobado distintos tamaños de hilo?

[FlashBandit]

I'm truly sorry to be burdensome, but I'm having terrible troubles building my driver. I've built maybe ten now and all of them are severely microphonic. The coil actually whines at a high pitch without the guitar even being plugged into an amp. This problem is coupled by the driver's proximity to the pickup. I've potted in tons of different ways.

My latest contraption was to build a coil without potting and not wrapped around anything. I then wrapped the coil with thread and pulled the coil all tight in together. Then, I cut a cast out of a bar of soap to put the coil in and surround it with iron impregnated epoxy. I put iron powder in the cast and mixed an epoxy in that with the iron. I then stuck the small coil inside and let it dry. The dang thing is till microphonic and it's driving me crazy.

Please help! I'm wrapping the coils as tight as I can without breaking the wire. Should I wrap it a little looser? Am I not potting correctly?

Also, I'm not really getting sustain yet. I know the amp works strong, I almost accidentally blew out an ear with it. Will microphonic drivers make the sustain not work? What's going on? How do I diagnose my problems? I'm actually very surprised that more people aren't having these same problems, but please give me a hand. Thanks a million!

[zfrittz6]

Hola.

QUOTE(col @ Apr 14 2007, 10:27 PM)

One question Juán, did you try different wire guages ?

(¿Una pregunta Juán, intentaste diversas medidas del alambre?)

Col

Si he probado con varias medidas y con hilo de 0,18 mm. tambien funciona bastante bien, es decir un poco mas fino tampoco no se exactamente si es esa la medida pero medido con el micrometro me daba esa medida aunque la bobina que construi y es la que pongo el dibujo la hize directamente con hilo de 0,2 mm. porque se me termino el de 0,18mm. que es el que he utilizado en casi todas las bobinas que hize anteriormente y lo saco de unos motores de ventilador muy baratos, consiguiendo hacer las bobinas en menos espacio y mas concentradas con el, asi que creo que si deben de funcionar con hilo mas fino e incluso diria que se mejoraria con hilo mas fino si no fijate en los reles que trabajan a 12 voltios por ejemplo que utilizan hilos muy finos y el tiron que tienen es grande, tambien los altavoces de 5 watios por ejemplo el hilo que tienen es bastante fino y sin embargo funcionan bien y no se queman con 1 watio , creo que en las bobinas de carril que hemos hecho algunos en el foro de 4 ohmios siempre las conectabamos de forma que un carril anulaba la EMI de la otra es decir, en serie para que la EMI que emitia una fuera anulada por la otra sin embargo si te fijas en las conexiones que he puesto, y esto es muy importante, las dos bobinas estan conectadas para atraer ó tirar, en un impulso determinado, de la cuerda, y por lo tanto no para anular la EMI, en consecuencia al tirar las dos bobinas al mismo tiempo de la cuerda se necesita bastante menos energia para hacerla vibrar, con el consecuente ahorro de energia y menos EMI.

FlashBandit el hilo tienen que estar lo mas concentrado posible, te aconsejo que te fijes bien en la bobina que he he puesto arriba en el dibujo e intentes hacerla asi, pero creo que es un problema de amplificacion procura que sea la minima para ello necesitas una bobina mas eficiente y la clave esta en la construccion de la misma y en la forma en que se coloca en la guitarra, ademas de las pastillas que tengas en la guitarra, te aconsejo que las desconectes todas totalmente menos la del puente para hacer las pruebas y la pegues solo con epoxi sin hierro y muy apretada. ¿ Que circuito utilizas? si tienes el diagrama y lo puedes poner a ver si tienes algo que falta y lo que produzca ese chillido sea una oscilacion.

Saludos ( gracias David por la traduccion)

Edited April 15, 2007 by zfrittz6

[Avalon]

I'm truly sorry to be burdensome, but I'm having terrible troubles building my driver. I've built maybe ten now and all of them are severely microphonic. The coil actually whines at a high pitch without the guitar even being plugged into an amp. This problem is coupled by the driver's proximity to the pickup. I've potted in tons of different ways.

My latest contraption was to build a coil without potting and not wrapped around anything. I then wrapped the coil with thread and pulled the coil all tight in together. Then, I cut a cast out of a bar of soap to put the coil in and surround it with iron impregnated epoxy. I put iron powder in the cast and mixed an epoxy in that with the iron. I then stuck the small coil inside and let it dry. The dang thing is till microphonic and it's driving me crazy.

Please help! I'm wrapping the coils as tight as I can without breaking the wire. Should I wrap it a little looser? Am I not potting correctly?

Also, I'm not really getting sustain yet. I know the amp works strong, I almost accidentally blew out an ear with it. Will microphonic drivers make the sustain not work? What's going on? How do I diagnose my problems? I'm actually very surprised that more people aren't having these same problems, but please give me a hand. Thanks a million!

I can't claim to be an expert on coils, but i've just wound my third which seems quite enough, so i'll offer what help i can.

I think the amount of noise is dependant on how hard you're trying to drive it via the Ruby/Fet, i used Ruby as a practice amp on headphones, and everything works fine on full volume & gain (FET biased to 4.5v), but on the driver, im not sure you can get away with running it that hard.

The more power the driver is emitting the more EMI i believe it will attract, which might be why your drivers aren't working that well, but even with alot of EMI, i would imagine it should be sustaining the strings atleast abit (the wound E string atleast).

I would go back to basics abit as far as the coils go, out of the ones you have made, i would find the best one and experiment with that for now, and try to get your strings sustaining, track down the problem before you try solving it, because you're coils might be fine.

If your Ruby/Fet is working fine, then i would experiment with how its wired up first, depending which way you have the coil wired to the Ruby, it might be Harmonic mode, which takes alot more energy to get the strings virbating, so try reversing the wires, see if that changes anything.

What kind of noise is the driver making?

If its a high pitched sqeale, it might be to close to another magnetic source (your other pickups, a computer monitor will make it sound like that), so make sure you're testing away from anything that might interfear (for now atleast), and i would have your amp quite low and sit ait away from it to minimize its effect.

Is the noise Vic20 block noises (computery sounds?), the pre-amp might be driven to hard, back off the gain and volume to see if it stops it, i had this problem for a start, and had to strike a balance, but again this might depend alot on EMI (and maybe on the LM chip you use too, im on the LM386N-1).

I'd also check the magnets are facing the right way on the driver too, if they're on sideways you'll be losing most of the power in the wrong direction, so make sure the north or south side is facing through the driver.

Sorry if this isn't much help mate, but i would forget about the Drivers noise for now, and just try to get the strings moving abit, and once you have a positive test, then think about shutting it up

Best of luck mate.

P.S. i'd test the driver well away from pickups for now too, hover it over the frets (12th is good, but if its still noisy go abit futher).

Edited April 15, 2007 by Avalon

[psw]

I think the amount of noise is dependant on how hard you're trying to drive it via the Ruby/Fet, i used Ruby as a practice amp on headphones, and everything works fine on full volume & gain (FET biased to 4.5v), but on the driver, im not sure you can get away with running it that hard.

All good advice Avalon...

Yes, turn down the gain on the R/F amp till the squeal stops. The idea is to reach a balance, you only want enough power to get the strings to move, as they move the acoustic volume of the strings will increase causing more power from the amp and the drive will get stronger and stronger till the strings can't move any harder. This creates a kind of 'bloom' to notes, particularly notes picked softly. More drive will make the effect happen sooner but not harder.

Other things to look out for is that the driver's leads are kept well away from the guitar's pickups and wirings and that the guitar is pretty quiet, you don't want a lot of noise getting into the system. This could be a problem with single coils and an unsheilded guitar.

Keeping the driver and it's leads and such well away from things while testing should produce a result. Your coil look fine so the problem is probably in the setup.

Each guitar is a little different so there is a bit of trial and error required with some of this stuff...

Sorry it's taking so long, keep at it... pete

[Truth_David]

Hola.

QUOTE(col @ Apr 14 2007, 10:27 PM)

One question Juán, did you try different wire guages ?

(¿Una pregunta Juán, intentaste diversas medidas del alambre?)

Col, this is a translation of Juán's in depth reply to your recent question:

Yes, I tried various guages, including 0.18mm guage wire, which also works pretty well, that's to say a little finer guage - I'm not exactly sure of the measurement, but I measured it with a micrometer which resulted in this approximation. Even though the coil I built shown in the illustration was constructed with 0.2mm wire, I ended up using 0.18mm, which is the guage I used in nearly all the coils I originally built which I took from cheap ventilator motors, managing in this way to construct the coils within a smaller space, and with tighter windings. So I conclude that yes, a finer guage wire ought to work, and I would even say that it would tend to work better - look at the relays which run at 12volts for example, which use very fine guage wire but which support a very powerful load, also 5 watt loudspeakers for example, which have pretty fine guage wire, yet they do not burn out using 1 a watt output - I believe that the 4 Ohm rail coils which several forum members have constructed - must always be connected so that one rail acts to cancel the EMI produced by the other - in other words they need to be connected in series, so that the EMI emmitted by one is cancelled by the other. However if you pay attention to the way my coils are connected, and this is very important, the two coils are connected in order to attract or pull the string following a predetermined impulse, so we are not concerned here simply with cancelling the EMI. Thus in consequence, pulling both coils at the same time as the string requires much less energy to cause the string to vibrate, with the resulting saving in terms of energy, and also produces less EMI.

Flash Bandit, the wires need to be as tightly wound as possible. I advise you to pay close attention to the illustration of the coil I posted above and try to make yours like that, but I believe that this is an amplification problem. You need to try to minimize the gain used, so you are going to need the most efficient coil possible, and the key to this lies in the in the choice of construction shape for mounting it on the guitar.

Also, in addition to disconnecting the pickups in the guitar, I advise you to disconnect all except the bridge pickup completely in order to test everything, and I recommend that you glue it in place with only epoxy and without steel, and it needs to be very tightly wound.

Which circuit are you using? If you have the schematic post it here so we can see if there are any faults, so we can determine what is causing the squealing or oscillation.

Cheers, and thanks to David for the translation.

Hope this helps,

David

[FlashBandit]

FlashBandit el hilo tienen que estar lo mas concentrado posible, te aconsejo que te fijes bien en la bobina que he he puesto arriba en el dibujo e intentes hacerla asi, pero creo que es un problema de amplificacion procura que sea la minima para ello necesitas una bobina mas eficiente y la clave esta en la construccion de la misma y en la forma en que se coloca en la guitarra, ademas de las pastillas que tengas en la guitarra, te aconsejo que las desconectes todas totalmente menos la del puente para hacer las pruebas y la pegues solo con epoxi sin hierro y muy apretada. ¿ Que circuito utilizas? si tienes el diagrama y lo puedes poner a ver si tienes algo que falta y lo que produzca ese chillido sea una oscilacion.

Saludos ( gracias David por la traduccion)

You asked what circuit I was using, I'm using the Fetzer/Ruby diagram from the front page of this thread with a connector between pins 1 and 8 instead of the gain pot.

O.K., I'm starting to realize that either I can't pot drivers, or there is only so much you can do to protect them from microphonics. I'm finding out though that there might be a problem with my circuit now, and the driver problem is related to it. The circuit was perfect before, but apparently something's come up and I don't know what. I plugged in to headphones and found that the circuit produces a squeal that goes microphonic in the driver. If I physically touch the ground of the circuit (or anything grounded like the bridge or strings) the high pitch squeal produced by the circuit goes away. I think that the circuit isn't grounded properly, but I don't know what to fix. Any suggestions?

Also, the microphonic problem I've been having is actually two things. Number one is listed above, and the second problem is EMI feedback between the pickup and driver. The first problem is constant no matter the driver's proximity to the pickup, but it goes away when I touch the ground. The second problem is related to the driver's proximity AND orientation to the pickup, but I know I can't fix this any time soon since it's the matter of much debate right now.

Anyways, any help you can give me with the grounding issue would be greatly appreciated. Oh, also, have any of you read the patent for the sustainiac system? There's some good material in there including diagrams and stuff. For their circuit, they make it a little more complex and efficient. The signal chain goes:

Signal > Preamp > Phase Shifter > Automatic Gain Control > Limiter > Current Booster > Driver

This might help Col and his ingenious development of the AGC circuit. They also have alot of different Ideas for drivers and stuff. Useful information, especially if you understand it I don't Anyways, here's the link for the text: Sustainiac Patent

They also have all the images at a link at the top of the page. If your internet can't show "tiff" images (mine couldn't) download the freeware "AlternaTIFF". It is incredibly useful for viewing the patents here and has all sorts of great features.

Let the development continue! I just keep thinking, "The people's sustainer is almost here!!!". Excited? Me too.

[psw]

You asked what circuit I was using, I'm using the Fetzer/Ruby diagram from the front page of this thread with a connector between pins 1 and 8 instead of the gain pot.

I would recommend a 10uF cap between pins 1 and 8, even if you don't have a gain pot (which could be of use to back it off a little, BTW).

In fact, it is probably worth someone checking that diagram, I was never sure of the Fetzer / Ruby thing and have never actually built it, perhaps something is missing in the diagram or needs to be added. I use a generic LM386 circuit and a two transistor preamp with a bit more gain. There is no secret mojo in there, the F/R is adequate and has worked for quite a few people.

The patents have been discussed a bit in the past. My approach was to dispense with a lot of their circuitry and concentrate on the development of a simple driver design, the thin driver, that I hoped would not require frequency compensation and the like. Col has come up with another unique twist in the feed forward compressor to give the device a little more sophistication and control.

I hope to develop a new basic circuit idea with the TDA7052 and signal phase switch before the power amp section, possibly in a modular kind of design and operated via a rotary style switch. Another development could be a mid driver for strat type guitars and such, but this would most likely require a dual coil driver of the like that has been posted recently...

Anyway, if you get a handle on your circuit problems you may find you have several workable drivers there flash...perhaps try a small speaker as the phones may not be an 8ohm impedance... pete

Whooo...over 100,000 visits...I should be a VIP around here!!! Amazing thread, thanks to all who continue to keep the thing alive

Edited April 16, 2007 by psw

[flickoflash]

I have been very impressed with the discussion & developments that have been discussed on these threads.

I have started a new forum community for Les Paul Guitar lovers & invite you to join & participate in the development group for pickup design & sustainers

http://www.mylespaul.com/forums/

http://profile.myspace.com/index.cfm?fusea...endid=174765726

ToneFreaks

Tesla’s Coil “F.A.P” Pickup Development Group

Sustainers X-Factor Project

Thanks, Flick

link works now www.mylespaul.com

Edited April 16, 2007 by flickoflash

[Avalon]

Hi guys, just alittle progress update to how im going about my sustainer.

I've been fiddling about with various setups, and have found that outputing from a spare port on my Pod (and V-Amp 2), to the Ruby/Fet, then to the driver (hovered around near different frets) creates a very effective feedback driver.

So im now thinking about changing my direction towards a silient feedback speaker (that won't require modding the guitar).

Here is a little sound sample of a test i just did with it:

http://www.snapdrive.net/files/334964/Driver_Test.mp3

Im going to build some more powerful drivers (and maybe use a more powerful magent) to see if i can get a good ranged feedback driver made, and have it as a desktop device.

Obviously it will still have the EMI issues, but i think it could be an interesting idea to follow up (as you might hear on the sound sample), so for now im going to pursue this idea and i'll keep you posted on how it go's (and any idea/feddback on the idea very welcome ).

[col]

Hi guys, just alittle progress update to how im going about my sustainer.

I've been fiddling about with various setups, and have found that outputing from a spare port on my Pod (and V-Amp 2), to the Ruby/Fet, then to the driver (hovered around near different frets) creates a very effective feedback driver.

So im now thinking about changing my direction towards a silient feedback speaker (that won't require modding the guitar).

Here is a little sound sample of a test i just did with it:

http://www.snapdrive.net/files/334964/Driver_Test.mp3

Im going to build some more powerful drivers (and maybe use a more powerful magent) to see if i can get a good ranged feedback driver made, and have it as a desktop device.

Obviously it will still have the EMI issues, but i think it could be an interesting idea to follow up (as you might hear on the sound sample), so for now im going to pursue this idea and i'll keep you posted on how it go's (and any idea/feddback on the idea very welcome ).

Great idea...

I imagine some sort of stand mounted device, during a 'performance' you walk up to is and position your guitar near the stand mounted driver... like jimi 'addressing' one of his marshals... and you can get various types of feedback and also mucho control by moving the guitar... also removes any issues caused by having to mount the system on the guitar.... nice idea, and possibly a really good product .. You could have a footswitched box for changing harmonic modes modes... and possibly a detatchable handheld 'bow' device...

The only real problem (and its a biggie) is that you would have to get your strings _really_ close to the driver when using it. The power of the driver falls off with the square of the distance (i think?)...

current system works well up to about 3mm from strings... 6mm gap would require 4 times the power... 12mm requires 16 times.. you see where I'm going with this... for you to have a setup where you could wail on your axe while waving it around inches away from the driver and have it still work you would need a mamoth driver and a heafty power supply... you would also have to start worrying about much worse EMI issues... e.g. what about your bass player... (not to mention public safety issues )

How close would you need to be to a 100watt driver ?... well, if 1watt needs 3mm, then 100 will give about 3cm range..

what about 1000watts ?.... somthing like 10cm

so for the device to be practical you probably need somthing like a 1000watt amp/driver combo ... doesn't sound very practical :-D.... although you can get some pretty compact 1000watt class-D amps, and the driver would probably keep you warm on those cold winter nights...

Of course all this is assuming I'm remembering correctly about the power of the magnet falling off with the square of the distance.. can anyone confirm this ?

cheers

Col

[Avalon]

Thats the real issue i guess, getting it to a workable state.

My test was done using the driver handheld, which isn't an option if your actually playing anything, and as you mentioned was close to the strings (3mm'ish), which also isn't ideal when playing, so there is definately alot of thought needed, but that can be half the fun

Anyhow, i'll see where it leads, and thanks for the feedback

[FlashBandit]

OK, I'm tracing alot of my problems back to a high pitched sound produced by my Ruby/Fetz circuit. I find that if I touch the ground/common with my hand, this problem mostly goes away. I don't get it because I only touch the ground, nothing else. This problem is NOT related to feedback between the pup and driver because the loud ringing is apparent when the amp outputs to headphones. This high pitch squeal causes microphonics in my driver that wrecks the efficiency of it. How do I fix this problem so that I don't always have to be in contact with the ground? I think there may be a problem with the trim pot (see the main diagram), but could that be causing it? Thanks!