psw

LK : Unfortunately I don't have a piezo hex PU. Do you know of anywhere someone has made one. I've seen simply putting buzzer piezo's on the bridge but not hex. There maybe a problem with handling noise. You've probably seen my enquiries on that on other threads. I still can't find a better access to piezo materials other than buzzers! Coil prototype 1 has been the most successfull in terms of power and sensitivity. This may be a product of it's ferrite core, that it is only focused on one string, it is 4 ohm rather than 8 ohm,etc. A major drawback however, is how directional it is. Because of the requirement to locate it at the end of the fretboard near the string centre, bending strings takes ithem out of the driving field. Also the driving force is almost entirely up and down resulting in the string crashing into the frets. As a result I'm moving towards a design that operates across all of the strings and creates a movement from side to side. Coil prototype 2 seemed to achieve this but is a little rough. It utilizes a special core and magnetic "shield" which I call a "cage" which disperses the power of both poles of the magnets towards the string and in such a manner as to create side to side driving. I'm up to coil prototype 3 at the moment. This coil is 70mm long, 10mm wide and 2mm thick! Ive developed a method of bobbin construction that is cheap and easy but winding these ultru-thin elongated coils is a bitch! One interesting aspect of this coil is that it is flexable so can be bent slightly to the string radius - cool! This work may well lead to new PU design ideas as the driver is akin to a PU in reverse! I noticed that if i hold a driver above the pickup all of the signal is cancelled out even if is being driven by another PU. As a result -I'm making a duplicate air core of the same dimensions in the hope that, like a humbucker, the radiation of one will cancel the other, but, only one will have the magnetic energy to drive the string. keep contributing as progress is being made! psw

It pushes and pulls. I thought of driving it with a half wave amplifier but I believe that the constant positive charges in the electromagnet will effectively produce a static magnet as the core won't have time to demagnetise between pulses. The negative cycle of the AC signal speeds this demagnetisation process. I could be proved wrong and so have experimented with ferrite cores as, although they take magnetism well, they don't hold it as well as iron and so are theoretically more responsive. The current working prototype is a hollow ferrite core and works well and may have addressed some of my concerns about phasing mentioned in earlier posts and in all but the ebow patent on electromagnetic sustainers. My latest model is yet to be wound but has a semi-solid iron core and will have a wide coil and 7 magnets between the strings. The main coil is 2mm thick and will be wrapped with a secondary coil array at right angles to encourage some side to side or circular movement. I may need to incorporate a sheild system that I devised for pickups influenced by the LACE pickups to limit stray radiation. thanks for your interest psw

The sustainer is still going on it's original battery! (Not continuously of course) So my next prototype is for all six strings and has a coil only 3mm thick. My idea is to make it small enough to tape to the scratch plate, not replace pickups or to invove routing the guitar. The present prototype works well but vibrates the string up and down only. This causes the string to hit the frets. I would be interested to hear is anyone has some ideas to vibrate the string more from side to side, or round and round as it naturally would. Also, a little less technical. How or what controls would people suggest for it. You could go simple with just an on off switch. A phase switch. An adjustable sensitivity control, perhaps on a sliding pot, some internal effects on the drive signal, LEDs ? cheers psw

Sick of seeing new models come out with stupid, uninspiring names, or worse still, numbers! Have you got some cool model name ideas. If so, let's hear them

Hey Ansil, are you thinking what I'm thinking? Seriously, i've been doing similar things with putting controls on pickups. So far passive swiching like phasing, coil taps and filters (caps, etc). What i've been working on is using micro tactile switches (it's hard to find one's that latch but they're out there) Ive mounted them on the top ends of single coils on either side of the strings but you need to have a non-standard coil design . That's why I got into these rare earth magnets as their power means that you can miniturize much of it. As for sideways coils it has been done before - mainly gibson. And there is a design in Animal Magnetisim For Musicians which uses a sideways coil with blades to redirect the magnetic field. One benifit of placing the coil on its side is that if you have your magnets also on their side, running along the string, you may use far more powerful magnets and less turns. It seems possible to make a powerful low impedance pickup in this way which would naturally be less noisy and passive. I tried to use surface mount inductors to make a hex coil in an active pickup but got frustrated. Their cores are ferrite and just right to mount a 5x1.5mm R.E. mag to them. By wiring them alternately and reversing every second mag you diffuse the field (they are attracted to one another) causing less string pull but still retaining the power to the coils. The signal would be low but with active electronics it should work - in theory. Perhaps you'd like to have a go, theres no winding involved! I mention all this because, in order to get your controls on board, smaller is better and designs as you describe enable better usable space. By the way, Schaller make a humbucking sized pickup with screws where you would expect pole pieces. Actually they are EQ controls. They cant be adjusted on the fly as per your design though. As for my latest coils. My sustainer prototype coil which is currently working, uses a ferrite core and RE mag and is only 5mm thick. Plenty of room for the circuitry below even in a single coil size. My next prototype is designed to be only 3-4mm thick and work on all six strings, even after being set in epoxy and has a steel "cage" and windings in two directions. It is powered by 7 RE mags only 3mmx2mm deep and a powdered iron/silicone core, so you see things can be really small (if a bit wide) Why so small, because I intend to mount it to the scratch plate with double sided tape. No routing etc. Anyway, food for thought You seem to be working in the right direction psw p.s It looks like a humbucker and I'm not inclined to take apart my 60's Les Paul just at the moment and my test guitar still only has one string and is made of pine so won't do it justice.... good luck

Ansil, Keep working on it! Most people prefer a stomp box to a purpose built guitar so it will probably be more acceptable. What I'm trying to achieve is an add on that offers a huge range of natural techniques to the guitar itself, simply, cheaply and with as little modification as possible. Perhaps you can help with this. I need to put in a switch so that, when the driver is activated, only the bridge PU is connected. Also, I have a neat little encoder "pot" with a push-push switch. I know this is getting into digital territory, but has anyone tried using this type of control for effects and stuff and would it have a place in this application do you think? Also, I'm looking to build in some simple effects into the driving chain (tremolo, etc). Has anyone got any thoughts on this? Early experiments with a flanger were really weird! Ansil, since your looking at synth type stuff. Perhaps there is a place for it in my type of sustainer. Consider this, a synth note generated from the played note, driving the string. The string would feedback with characteristics of the synth note would it not? Just a thought, what do you think. thanks p s w

Ansil, that sounds interesting! Is it like the Boss feedbacker Distortion? The schematic is around somewhere on the web. If so, is the feedback note synthesised and monophonic as the Boss appears to be? PROGRESS REPORT Meanwhile...... My little sustainer is still going. I've set it up on my test guitar with double-sided tape (the inventor friend) and croc clips. I found that the coil is more effective when the magnet is placed below and attached to metal (in this case the end of the truss rod!). People following this thread will know that I am using a ferrite core. I might try an iron core as it may be more effective after all! If the string is bent off the centre of the coil, away from the core, the feedback dies away. As it is in the neck position, any string bending is effected in this way. Perhaps some sort of blade configuration maybe necessary but problematic as I'm still going with the six coil driver - any thoughts guys? The driver causes the string to vibrate vigorously in an up and down motion - not the guitars natural circular manner - causing the string to rattle against the frets. This does cause some really cool changes in harmonic feedback and doesn't prevent the note from sustaining but is not ideal. Anyone got any thoghts on how to get the string to move from side to side? This is the motion initiated by a violin bow. My 9 yr old came in and played with it. She said it sounded like an accordian! What would she know. She plays violin, but sometimes she has the tact of a drummer I've tried puting various caps on the input to no great effect so am leaving them out for now. I still can't get it to run ebow style. Ive tried hooking the driver to a second pickup, out of the signal chain and get plenty of squeels and interferance but no sustain. Why, I don't know, but it only seems to be driving properly from the bridge pickup that is connected to the signal chain. It will do this even with the amp turned off so I don't get it. The ebow patent suggested that the driver and sensor could be one and the same! I am having trouble coming to terms with this idea. Anyone got any thoughts? (LK?) Ansil. Can you tell me how to get more range from the sustainer mod circuit. I'm finding that I can't get the control of gain that I want. I'm using a 1k trim pot. I want to be able to reduce the output further but retain the present max out. Anyhow, the quest continues.......... psw

Anyone know where I can get measurements or body plans for the Iceman? When I was in school (many years ago now) the hot shot guitarist played one. It was a beautiful Korina twin humbucker similar to a classic explorer.

Hey Ansil, good to see your keeping up with this topic! I've got to thank you for getting me on to the simplicity of your 386 amp circuit for your sustainer mod. Can you tell me the purpose of the input capacitor. I've been using only the output capacitor to great effect but my DIY electronics theory is a bit iffy! Perhaps you can enlighten us on why electromagnetic sustainer circuits, as described in the patents, are so complex. Also, do you, or anyone else, think that it is possible for the driver and sensor to share the same magnetic field (say in a stacked configuration) or is it going to oscillate wildly by definition? psw

what I was thinking of doing was pressing sheet aluminium into a shape the strengthening inside with epoxy and timber etc.

Actually I live the inbetween sounds but it has to go somewhere! It is also a comprimise position. As LoveKraft pointed out, it is easier to drive the string nearer it's centre. But too far away and I anticipate problems with string bending. Also, some guitars only have two pickups, the bridge and neck PU's are by far the most used and really I only use the middle PU to colour the sounds of the others. Out of interest : I have a crap strat that I've done up with phase switching for each PU and a three way toggle like a gibson on the lower horn. This gives me N N&B B with the N&B position preset to in or out of phase for a wide variety and easy changing. The centre tone control is used to fade in the centre PU (in or out of phase) to color the sound. I find it a far more effective control than a standard tone. psw

Your right about the mousetrap alright LK The ideal configuration that I'm aiming for is: a drop in replacement for the centre coil. Preferably with the drivers, sensors and ciruitry in the same unit. I'd like to run it from a rechargable battery (i'd put a charging socket on the back plate). I'd also like to put the control switches as miniture push buttons on the ends of the pickup (an idea Ive been using for new pickup designs for phasing and voicing made possible by the use of miniture RE magnets and changes in coil design) I'd like to have it run more efficiently than present devices (am exploring half wave amplification in this regard) [ p.s. your right about the S+H idea SK. I think but there maybe simpler ways, perhaps a high speed flip-flop] I'd like to address the polyphonic problems associated with the present designs I'd like to see the centre coil still usable as a passive device when the sustainer is not functioning. I'm thinking of combining the driving and sensing coils to achieve this. I'd like to set the whole thing in epoxy so none should know the secret of how it works! psw

Anyone had experience making an aluminium or like body or played one? Let us know! psw

I'd always wondered why neck shapes are symetrical. My hand isn't. Also, perhaps a thicker neck would be more comfortable at one end vs. the other, for chords v. lead. Just a thought

I wonder why you'd use that for a fretboard. PAPER? How can I find out more?

LK Just discovered a short or something in my test coil and the other that I tried, a "magnetic piezo" is an experimental idea that was not magneticaly uncoupled, or uncoupled enough! I see what you mean but If they are that close together in the Ebow surely their will be some magnetic coupling? Anyways, I'll do a more reliable test in the near future and hope to be as pleasantly surprised as I was before in ignoring the phase problems that apparently aren't of as much concern as I thought! psw

Yep! thats what I thought. The carbon fibre is for strength but alot of these epoxies are tough and can be mixed with fillers, maybe even stainless steel fillings. I'd like to know what the experts think, fizzy-E I've heard that guitar manufactures are using "ebonol"? Any one know what that is - Imitation ebony?

ThanksLK Just the sort of thing I was after. I really just want to buffer some pickup ideas I have. Remarkable translation me thought: "Of theories not it will be. Continuous practice" Good advice for us all psw

Well Jehle thats interesting. I kind of thought that the pickup might self destruct by carrying the amplified signal. I know Micheal Brooks Infinite guitar uses a seymor duncan PU to drive his guitar though. Can you give me some more details. Was the driving pickup single coil or humbucking? Particuarly powerful? Anyone got any thoughts on why the sustainiac, fernades and floyd rose kramer systems are so complicated and expensive if this idea works just as well? I'll give it a shot. but it hadn't worked for me before (perhaps I wasn't doing it right back then). Perhaps a hybrid where you have individual driving coils for each string but taking the signal from the guitar's pickup with filters and power controls tailored to each string and frequencies is the go. great contribution! psw

Thats where I'm going with the hex idea but I'd like to keep the sensors and drivers in the one package like the Ebow. I don't want to ditch other pickups to just for this gizmo. Actually, I described the squeel wrong. When I tried a pickup, separate from the drive chain, thats when I got the characteristic feedback squeel. I tried various configurations, side by side (ala ebow), stacked and sharing the same magnet, non-magnetic piezo drivers, etc. LK: That's why I still don't know why the ebow doesn't do the same to itself and/or the signal pickup! The squeel I refered to when using the guitar's coil is controlled. Moving the driver coil around produces an amazing theramin type sound. More magnets raises the frequency, different angles and locations slide the tone. The sound is unrelated to the string but is induced in the coils. How about filter caps on the input. I'm not using any. Would they help cut back on the feedback squeel between driver and sensor? What are they for (I know they are commonly used). The driver/sensor idea I had was to Have the positive cycle of the wave sensed by the coil; A sample and hold chip would store it: The wave passing through zero would trigger it: An amplifier would increase and invert it back through the coil through the negative cycle. The idea being to sense the positive cycles and drive the negative. Avoiding feedback squeel as the sensor and driver would not actually be on at the same time. thanks to everyone for their contributions and encouragement, progress is being made me thinks! psw

LK Well I still get electromagnetic radiation which makes it squeel violently if it gets to close to the driving pickup, so I still don't get how the ebow does it! Biohazard - I've been trying various things for a couple of months this time around. Its something I just keep coming back to. It looks as if all those patent guys were being too clever by half with the phase problems etc. Maybe you were right LK. or maybe I'll come across them as the prototypes get more sophisticated. Basically I used the 386 sustainer mod circuit of Ansil's (couldn't get the sustainer mod to do much by the way) to drive a coil which I held close to the string. I used a ferrite bead 4mm x 5mm high as the core. I have been experimenting with ferrite as, while it is easy to magnetise it does not hold it's magnetism like iron does. My theory is that alot of problems with the phases involve risidual magnetism in the core and the reactive speed to rapidly changing AC signals. A 5x1.5mm rare earth magnet was attached to the outside (bottom) of the coil. A smaller mag could be inserted within the ferrite for the same effect and this would be a better thing. The coil was, I think, about 300 turns of 0.2mm enamelled wire. I used a silicone gasket RTV as I was winding as a kind of potting. I didn't want vibrations in the coil causing problems. The final coil measures 12mm round and comes in at 4 ohms exactly. It will produce quite strong continuous sustain even at half strength so seems to require little power to run. The next stage is to make a multi-string driver to fit in a strat cover for the centre position. I might find that a larger coil, or multiple coils cause even more radiation so I have come up with a kind of humbucking configuration and various focusing plates and shielding ideas if I run into problems. The signal came from a bridge position cheapo single coil pickup which also ran to the amp. I tried driving it from a small coil but it lacked power I think. I tried other configurations to make an independent ebow copy but could not get it to stop squeeling! Can anyone think of a way of using the same coil to both pickup up and drive the string or am I expecting too much.

How about a transformer or something? I'm still not getting the need for a buffer when I get a quite a strong signal from it. Here's the thing. I tested an idea for a magnetic/piezo hybrid. Basically a piezo element that is vibrated by the magnet field on a guitar string. I tried attaching it by double sided foam tape but this flexability allowed even more vibration to occur. Perhaps I should have glued it down or perhaps used silicone for a little less spring. The next time I work on this I'll perhaps try even smaller piezos. Does anyone where you can get piezo film?

Anyone know of a way to suppress handling noise and microphonics in piezo pickup designs? Also. I've seen in this forum comment that combining piezo's with pickups without some preamplification causes problems when combined with magnetic pickups (loading, tone shaping?) Can these problems be addressed passively. (eg caps to roll off the high end). If it must be active has anyone thought of using a very low drain circuit running off a little lithium cell. I believe they can last up to 10 years. (Or hearing aid technology) cheers psw........................................ ........................................ P.S. For my latest success with my sustainer prototype see the thread Sustainer Ideas

I have made a working prototype practical sustainer!!!!!!!!!!!!!!! Yesterday I suscessfully put together a magnetic sustainer. The device uses a compact coil (5mm round x 4mm deep) with a ferrite coil and a tiny Rare Earth Magnet. It is powered by a 9v battery and a tiny and very simple amplification circuit. It was tested on my one string test guitar. This is a crap guitar neck bolted to a piece of pine with a very low quality single coil pickup taped to it. This test guitar is used because it has low natural sustain and high suseptability to hum etc. It is my worst case senario instrument as I figure if it works on that it will work on anything! Electromagnetic radiation is present but only when the coil is close to the guitar's sensing pickup. It will successfully drive the string at about the centre strat pickup position without noise. This was one of my aims as the eventual design idea is to slot it into this position. Reversing the polarity of the magnet (or the coil) suppresses the fundumental and drives the string at higher order harmonics (eg a fifth above, etc). The sound. Think the intro to U2's With or Without You. Infinite clean sustain! Oh, Happy Day

I think it was more a matter of production. Apparently they injection moulded the board but it warped when it was taken from the mold. They had to let it cool in the mold which took time and money. Such was the interest that they had to revert to machining them from aluminum, which most of them were. I thought that they just went too far on a basically good idea. Apparently there are examples of medievil lutes with stepped boards. The electronics were ridiculous. Not enough KIS principle. I was wondering if epoxies, etc hadn't come further by now in wear resistance. The parker fly is epoxy albeit with SS frets. Perhaps a type of teflon would have so little string resistance that it wouldn't wear the board or the string at all! Pete SW