psw Posted May 31, 2007 Author Report Share Posted May 31, 2007 Ok Sustainer guys, I'm back...don't know what happened to PG...seem to have run out of bandwidth for a bit...perhaps this thread has gotten too big... Anyway, I'm sure you will all be happy to know that I'm getting enthusiastic about doing some more work on this and putting some of my thoughts into action...certainly, I'll be looking for support and advice and sharing what I come up with with you all... So, first things first... My guitar will need to be modified to take the sustainer...here's the guitar for those whoi may have forgotten... And here's the control cavity... So, we are looking at a Mahogany Squier strat with JB seymour designed Pup at the bridge and alnico single coils in the neck and bridge... Normally of course I advise people to test their devices out before worrying about installations and such, but having done this before and given the progress since I last built one, I feel pretty confident of a success with the mid-driver concept. At worse, if it fails, I could put it in the neck position... The guitar has no scratch plate, as you can see so any holes in it will be permanent...I am not about to take the router to it as I did on the tester guitar on this one...so I have to fit all the circuitry and battery in this small area, as well as have sensible switching... My solution (although push pull pots would work) is a row of three toggle switches behind the three chrome knobs and a little below...so how will I fit those in? Well, I think I can safely take a router to the control cavity set deep so as to undercut it enough to fit the switches and not effect the finish or control cavity cover plate. I could use the same technique to under cut behind the trem block to fit a battery, accessable from the trem cover...neato The benefit of this guitar is that testing can be done before making permanent holes and such in it from wires out the back (tricky on a conventional strat)... I am thinking of a dedicated driver (not a pickup combo like my present guitar) in the mid position....some of the details need to be ironed out yet...so the middle pickup needs to go. With this in mind I will be forced to rewire the guitar, and while I didn't wish to get too tricky, I can't resist...plus loosing the mid pickup means loosing those inbetween typically strat sounds so I feel I need to compenstae a little...anyway, I can so why not... To this end I have ordered a "super-switch" and have been consulting with the good fella's over at Guitar Nuts 2 - Strat Mod Thread...(BTW, if you can't get enough sustainer thread here, there's another one there as well...Guitar Nuts 2 - Sustainer Thread...a lot more concise than this one... There are a few options that will lead a variety of sounds, even with the loss of the middle pickup. Using the super switch and one toggle there is a lot you can do, I may even be able to use one of the tone controls as a progressive coil splitter for the HB...and there are novel tone controls with LC circuits to create a mid scoop, similar in sound to the inbetween sounds...so it may be all gain as far as that's concerned... That leaves two toggles for on/off and harmonic functions for the sustainer...with a dedicated mid driver, these can be much cheaper smaller switches than the expensive 4PDT, and easier to get!!! There is probably enough room in the control cavity for all the circuitry (a little crowded) but my intention is to have the preamp in there and the poweramp in the trem cavity, or even under the driver itself... As I say, first things first with this...rewire the guitar and leave that mid pickup space free to experiment with... At the moment, I am thinking thin twin blades, similar to the ideas of Juan and Avalon, parralel coils about 3mm deep and pretty close together. I may incorporate some magnetic sheilding on either side, but I want to fit it within a SC cover, perhaps with the top cut off...I even have some plans to revisit some ideas I put into the Hex devices like LED indicator and momentary switching...but perhaps that will have to wait for the next one, once the prototype prooves successful... It's nice to be looking at participating and adding to the thread in a practical way again...I hope I can get photos but all I have is my camera phone at the moment...still the pics of the guitar didn't turn out to bad... pete Link to comment Share on other sites More sharing options...
Avalon Posted May 31, 2007 Report Share Posted May 31, 2007 Ok Sustainer guys, I'm back...don't know what happened to PG...seem to have run out of bandwidth for a bit...perhaps this thread has gotten too big... Anyway, I'm sure you will all be happy to know that I'm getting enthusiastic about doing some more work on this and putting some of my thoughts into action...certainly, I'll be looking for support and advice and sharing what I come up with with you all... So, first things first... My guitar will need to be modified to take the sustainer...here's the guitar for those whoi may have forgotten... And here's the control cavity... So, we are looking at a Mahogany Squier strat with JB seymour designed Pup at the bridge and alnico single coils in the neck and bridge... Normally of course I advise people to test their devices out before worrying about installations and such, but having done this before and given the progress since I last built one, I feel pretty confident of a success with the mid-driver concept. At worse, if it fails, I could put it in the neck position... The guitar has no scratch plate, as you can see so any holes in it will be permanent...I am not about to take the router to it as I did on the tester guitar on this one...so I have to fit all the circuitry and battery in this small area, as well as have sensible switching... My solution (although push pull pots would work) is a row of three toggle switches behind the three chrome knobs and a little below...so how will I fit those in? Well, I think I can safely take a router to the control cavity set deep so as to undercut it enough to fit the switches and not effect the finish or control cavity cover plate. I could use the same technique to under cut behind the trem block to fit a battery, accessable from the trem cover...neato The benefit of this guitar is that testing can be done before making permanent holes and such in it from wires out the back (tricky on a conventional strat)... I am thinking of a dedicated driver (not a pickup combo like my present guitar) in the mid position....some of the details need to be ironed out yet...so the middle pickup needs to go. With this in mind I will be forced to rewire the guitar, and while I didn't wish to get too tricky, I can't resist...plus loosing the mid pickup means loosing those inbetween typically strat sounds so I feel I need to compenstae a little...anyway, I can so why not... To this end I have ordered a "super-switch" and have been consulting with the good fella's over at Guitar Nuts 2 - Strat Mod Thread...(BTW, if you can't get enough sustainer thread here, there's another one there as well...Guitar Nuts 2 - Sustainer Thread...a lot more concise than this one... There are a few options that will lead a variety of sounds, even with the loss of the middle pickup. Using the super switch and one toggle there is a lot you can do, I may even be able to use one of the tone controls as a progressive coil splitter for the HB...and there are novel tone controls with LC circuits to create a mid scoop, similar in sound to the inbetween sounds...so it may be all gain as far as that's concerned... That leaves two toggles for on/off and harmonic functions for the sustainer...with a dedicated mid driver, these can be much cheaper smaller switches than the expensive 4PDT, and easier to get!!! There is probably enough room in the control cavity for all the circuitry (a little crowded) but my intention is to have the preamp in there and the poweramp in the trem cavity, or even under the driver itself... As I say, first things first with this...rewire the guitar and leave that mid pickup space free to experiment with... At the moment, I am thinking thin twin blades, similar to the ideas of Juan and Avalon, parralel coils about 3mm deep and pretty close together. I may incorporate some magnetic sheilding on either side, but I want to fit it within a SC cover, perhaps with the top cut off...I even have some plans to revisit some ideas I put into the Hex devices like LED indicator and momentary switching...but perhaps that will have to wait for the next one, once the prototype prooves successful... It's nice to be looking at participating and adding to the thread in a practical way again...I hope I can get photos but all I have is my camera phone at the moment...still the pics of the guitar didn't turn out to bad... pete Sounds great mate, and i can honestly see it working well in that guitar, the extra distance you have available between the bridge and neck (over my guitars atleast) i think will be more then enough to have a working mid driver there, the tests i did with my dual rail were very good up until about 10mm away from the bridge pickup, when it started to interfear with the bridge, and it looks like you have twice as much room to work in. As for the board, i just about fitted the F/R in my cavity with no alterations (the two previously installed switches did help with that though), the board itself is atouch bigger then a 9v battery in width and height, and not as deep. My control cavity looks does look atouch wider, but it definately looks ig enough for the job to me, best of luck with its construction mate and i'll look forward to seeing its progress Again i've not got much to report on my own progress, still just been enjoying the mark 1 installation in what little time i've had the last couple of weeks, but im sure to start work on it again real soon. Link to comment Share on other sites More sharing options...
donbenjy Posted May 31, 2007 Report Share Posted May 31, 2007 right...no idea what's wrong with my F/R but even with the right transistor, all that happens is that if I turn the bias control up to full (9v) then I get a squealing noise, which isn't to do with the trasistor, because it still squeals without anything there...and there is zero effect when I touch the hot input or play my guitar through it! I'm wondering if my earlier "attempts" with the PNP they gave me might have damaged the lm386...I'm about 90% certain that my circuit is correctly wired and not shorted anywhere, so I'm kinda at a loss here! anyone got any troubleshooting tips, either generally or specifically for the F/R (nominal voltage readings/resistances etc.) I did mention the bias trim pot was smoking the first time, so maybe I melted something in that! I'll try removing that and sticking a suitble resistor in there instead. tbh, without trying to sound bigheaded, all my previous circuits have either worked straight off, or I've wired something incorrectly, so proper troubleshooting to isolate the problem is kinda new to me! :S Link to comment Share on other sites More sharing options...
Avalon Posted May 31, 2007 Report Share Posted May 31, 2007 Well IC's can sometimes be troublesome, but the LM386 doesn't seem to be one of those kind (or as far as i've found so far anyway). As for the F/R itself, with the power bias control on full, squealing will be the only thing it should be doing tbh, it wants to be 4.5v, to set this you'll need the multimeter on the board, one contract on the ground (with a croc clip if you have one with it) and the other contact at the Collector/Drain leg of the transitor, with the Meter set to DCV - 20 (thats the setting on mine atleast). Now im not sure how everyone else go's about the next part, but i bias it to 4.5v (as close as i can get) with no input or output connected, this seems the best way to me so far. Have you tested your F/R as a pre-amp?, i put a stereo headphone socket the output (which i plugged my computer speakers into) and a jack socket on the in to test mine with, it really is the best way, because you can find pretty much any prob with it like this. The others are the slightly obvious things, capacitors being the right way around, no short circuits (get the meter out again), chip is seated correctly, and the right way around, the transitor pins to the right place. I would definately get it into pre-amp mode mate, and remember, even if you hear your guitar, it might not be quite right, take notice of how the volume control reacts and the power bias, as this will give you clues to what might not be fully functional. If it doesn't work at all, then something is definately very wrong, best of luck mate. Link to comment Share on other sites More sharing options...
donbenjy Posted May 31, 2007 Report Share Posted May 31, 2007 yeah, I've got 2 5w, 4ohm speakers in series that had loose wires, so I stuck them in the bread board...there's certainly a output to it - the speakers hum, but I can't get anything in at all...the trim pot is log, so it's really hard to adjust to 4.5V...but I've been jumping down from 9v, not up from ground, so I guess that make a slight difference.... Link to comment Share on other sites More sharing options...
Avalon Posted May 31, 2007 Report Share Posted May 31, 2007 Well i had abit of trouble with a small speaker on my board, i think it was impedence related, so i switched to headphones, earphones and computer speakers, which it worked perfectly with, so that might be worth a shot if you have any of the above. As for the pots, i know what you mean, half a milimeter in the middle seems to account for 2v, which isn't that handy, but for basic testing (especially as a pre-amp) the voltage isn't quite as important, in the ball park will do until its driver time, it just added/reduced some of the gain added to my guitar signal. Hopefully it will come to life for you before much longer, i'll keep my fingers crossed for you Link to comment Share on other sites More sharing options...
mrjstudios Posted June 1, 2007 Report Share Posted June 1, 2007 (edited) I have not tested it with my multimeter yet, but I believe that the "ballpark" sweetspot on my F / R was probably at about 4 volts. (It runs on a 9v when on full blast.) I'll get it out and check for ya... By the way -- progress on my non-sustainer guitar (so now I can focus on the sustainer one!) **The body design is Copyright 2007, MRJ STUDIOS** It is since put together and plays very well -- except the 6th "hardened steel" string clamping screw on the floyde rose broke in half......... More on that later..... Edited June 2, 2007 by mrjstudios Link to comment Share on other sites More sharing options...
donbenjy Posted June 1, 2007 Report Share Posted June 1, 2007 coolio! cheers guys! I love the finish on that guitar! what's gonna cover the control cavities on the front? or does it have a scratchplate on? actually, looking at the screw holes, it probably does! Custom or standard? I think a clear on would work well here! It'd be a shame to cover the artwork! Link to comment Share on other sites More sharing options...
Avalon Posted June 1, 2007 Report Share Posted June 1, 2007 Great stuff mate, it looks beautiful, is it built from scratch? or a repaint?, either way stella work though, looks awesome Link to comment Share on other sites More sharing options...
donbenjy Posted June 1, 2007 Report Share Posted June 1, 2007 (edited) that's not a standard strat/RG shape or routing, so I'd be inclinded to think it's built from scratch - unless it's some kinda unknown or budget model, but somehow I doubt it Edited June 1, 2007 by donbenjy Link to comment Share on other sites More sharing options...
mrjstudios Posted June 1, 2007 Report Share Posted June 1, 2007 (edited) Thanks guys! I'll take and post some more pictures soon -- whenever the Floyd Rose replacement screw comes and I can have a 6 string guitar again.... Yes, the body is designed built from scratch, and yes, there is white pickguard material near where the controls are. I made a clear scratchplate to cover under the strings though (good call donbenjy). As for the shape of it, it is designed to have an overall Strat / Kramer Baretta kind of size and feel, but with modifications that I prefer over the standard models (hey, it's my guitar, right?) First off, it has no strat pickguard, and the control nobs are arranged differently so that your wammy bar will no longer hit your volume knob. (You'll see later.) Second, the Floyd Rose is mounted about 3mm farther off the body, (which would make it easier to add a sustainer/pickup stacked model), and aligned directly with the neck -- something I call a "flat mount". In otherwords, the action is constant over the entire length of the neck since the strings are not angled down towards the neck from the bridge. Third, the Floyd Rose can be made either full floating or "EVH style" down only with the adjustment of 2 screws. And fourth, the body curve directly below the neck in the picture is cut much deeper than a standard guitar so it is easier to play on the high frets. Not sure yet if these mods would be good for anyone else, but like I said it's just my preference / ideas. If a really stable dual-rail mid-sustainer is developed sometime here, this guitar will be a candidate for it. As for now, I will work on my guitar "#XS002" which is a guitar built around the sustainer. **The body design is Copyright 2007, MRJ STUDIOS** But I would probably give permission if someone wants to use it for themselves. -MRJ STUDIOS Edited June 2, 2007 by mrjstudios Link to comment Share on other sites More sharing options...
mrjstudios Posted June 1, 2007 Report Share Posted June 1, 2007 (edited) Here is guitar #XS002 so far... **The body design is Copyright 2007, MRJ STUDIOS** But I would probably give permission if someone wants to use it for themselves Edited June 2, 2007 by mrjstudios Link to comment Share on other sites More sharing options...
psw Posted June 1, 2007 Author Report Share Posted June 1, 2007 Nice, I like that sustainer guitar shape...looking good. Will it be a single pickup guitar for sustainer simplicity? I had similar plans for a reverse strat sustainer guitar type thing (there is a thread some where), and I may well put something together (I have a copy LH neck, most parts, and an old gibson HB around somewhere)...at the moment though, I would like to see the sustainer as a more viable addition to existing guitars without limiting them (my sustainer strat comes pretty close)... Meanwhile, getting really interested again and looking forward to doing some experiments of my own on driver design and construction...got some definite plans... I have an alternative to the LM386 stage that should give out more power...i'd like to put out more power to give a more immediate and powerful effect...that means the driver design will need all the help it can get to limit stray EMI... Also coming up with other guitar ideas again...contemplating experimenting with a dummy coil below a HB to allow for splitting the HB but still being noiseless (kind of like a stacked design)... And, then there is the rewiring of my strat...so many choices and stuff to play with... The mid-driver has the possibility of some interesting "effects" from different pickup selections, particularly with advanced wiring schemes incorportatine different phase characteristics...this thing could have many modes selectable just from the selection of pickups... Sounds great mate, and i can honestly see it working well in that guitar, the extra distance you have available between the bridge and neck (over my guitars atleast) i think will be more then enough to have a working mid driver there, the tests i did with my dual rail were very good up until about 10mm away from the bridge pickup, when it started to interfear with the bridge, and it looks like you have twice as much room to work in. Yes...the extra length of the fender scale and the pickup style gives a fair amount of room to work with, but no more so than a typical strat, so it will be a good test for these types of guitars...a typical candidate for the project... Like everything, you have to try not to get too far ahead of oneself and take it a step at a time... pete Link to comment Share on other sites More sharing options...
psw Posted June 2, 2007 Author Report Share Posted June 2, 2007 whew...sold the house today, for those following my personal trials...this will free me up a bit and I can indulge in this project a little more... Got the super switch today so it is on for the first part, rewiring the strat to a two pickup guitar making room for a mid sustainer... Avalon... the tests i did with my dual rail were very good up until about 10mm away from the bridge pickup, when it started to interfear with the bridge does this mean that the mid driver exists, or it just wouldn't work for your guitar because of this restriction? I think Juan may have succeeded also, but it's a bit hard to tell in translation... Like Juan, I am thinking of using saw blades in my design (if their hardened steel isn't too hard to work with), though I am not sure how thin a blade might be too thin...hmmm Also, I'd like to try the parallel coil idea...I have a roll of 0.71mm wire around somewhere...so what are the specs for this type of thing again...I have to get the coils pretty compact if they are to fit the way I'd like, so I may have to add a bit of depth, while still being thin, to get the dimensions I am looking for... Any thoughts, and approximately how many turns to a coil, and to what impedance should I aim. Can anyone explain why a parallel coil may work better than a series coil arrangement (like col's)? Anyway...freedom and soon to be money, I feel more attractive already... pete Link to comment Share on other sites More sharing options...
Avalon Posted June 2, 2007 Report Share Posted June 2, 2007 Well the dual rail has always been in my mind as the mid driver, and the parallel designs seem far quieter then the serials, all my single coil size drivers have been tested in the mid position of my test guitar too, the parallel designs are the ones of mine that drove the strings and got anywhere near the bridge pickup at the same time. As for the dual rails construction, my first attempt was wound with 36 guage, but my full size humbucker is working great on the 38 guage, so im almost certainly going to use this on my dual rail, the difference in size alone is big, and so far it seems to be performing as well too. The biggest shame for me now is, to do any futher testing i have to open my test guitar back up, but i don't think i'll be touching the newly installed parts from now, i might even mod it slightly so i can test new designs without even opening it up, maybe add a stereo jack, make a special guitar lead up especially for sustainer & guitar signal output, might be an idea. Anyway, hopefully i can get a few things done this week too, im starting to feel back in my right mind again these last couple of days after a bad bit of flu, so time permiting, a few things to be doing Link to comment Share on other sites More sharing options...
mrjstudios Posted June 2, 2007 Report Share Posted June 2, 2007 Nice, I like that sustainer guitar shape...looking good. Will it be a single pickup guitar for sustainer simplicity? For now, I'm gonna route a single HB hole, and an extra large singlepickup hole for my single-rail sustainer. I don't have a spare HB yet though, so I'll stick 2 extra strat pickups in its place and only wire one to work. I have done some work since this picture, and all that is left to do now is to route the round-over edges, and the control cavity / holes for switches and knobs. -MRJSTUDIOS Link to comment Share on other sites More sharing options...
psw Posted June 2, 2007 Author Report Share Posted June 2, 2007 Hi guys...bringing a few posts forward so I can find them again...and for discussion later I suspect...this thread is too big... 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. quote name='zfrittz6' date='Apr 15 2007, 09:04 AM' post='324570'] 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 Hi guys, here's the first pics of the Dual Rail Humbucker i've made: And Its based on Juán's design from page 178, two 13.5 ohm coils, side-by-side, wired in parallel (first DPDT switch works serial/parallel). I must say the first signs are very good, in parallel mode, it runs in the neck position with the Ruby/Fet on full power siliently, thats a first for me (not sure about you guys), but also works well at the same gain level as all my previous drivers (easily equal to them at similiar levels), and as importantly, it works in the middle position at the same level of gain without interfearence. I must say it was abit annoying to build, i built the coils around a 2mm steel core (the thinnest i can find atm), and the coils just about take the 4mm i allowed for them (2mm either side of the core), but its a tight fit. I finished winding my stacked HB version of the above a couple of hours ago, so i'll be able to see how both designs compair soon enough, but im very impressed the Dual Rail design so far. Hola a todos os subo algunas fotos de lo ultimo que he hecho. bobina cuadruple de 13,5 ohmios cada una con hilo de 0,1 mm. La bobina funciona perfectamente en la posicion media y cabe en la cavidad de una single coil. Saludos pete Link to comment Share on other sites More sharing options...
psw Posted June 2, 2007 Author Report Share Posted June 2, 2007 Avalon Well the dual rail has always been in my mind as the mid driver, and the parallel designs seem far quieter then the serials, all my single coil size drivers have been tested in the mid position of my test guitar too, the parallel designs are the ones of mine that drove the strings and got anywhere near the bridge pickup at the same time. As for the dual rails construction, my first attempt was wound with 36 guage, but my full size humbucker is working great on the 38 guage, so im almost certainly going to use this on my dual rail, the difference in size alone is big, and so far it seems to be performing as well too. The biggest shame for me now is, to do any futher testing i have to open my test guitar back up, but i don't think i'll be touching the newly installed parts from now, i might even mod it slightly so i can test new designs without even opening it up, maybe add a stereo jack, make a special guitar lead up especially for sustainer & guitar signal output, might be an idea. Anyway, hopefully i can get a few things done this week too, im starting to feel back in my right mind again these last couple of days after a bad bit of flu, so time permiting, a few things to be doing OK...so I will be trying something similar...I imagine I will have to make a couple to get the dimensions right and to make something special, so I will try not to get too ambitious on the first go... I think the saw blade cores (as Juan used) are a good idea...these are highly magnetic and really cheap ones tend not to be hardened too well, so shaping them may not be too bad...I think it will be a job for an angle grinder though...lots of sparks and noise To recap the aims of this "next Generation" sustainer... Mid-driver that retains the use of other pickups in sustain mode Easier installation due to bypass operations being obsolete Improved response - the mid driver will have less difference caused by fretting action - better consistancy from note to note I will also be looking at changing the circuitry I am considering the TDA7052 BTL for the poweramp, replacing the LM386 circuit. This may give me more power so can cut the preamp down to a single opamp in buffer mode, switching the feedback and inputs to invert the signal and so create the harmonic effect (this has still to be worked out) I may use a switch jack on the guitar and have the preamp running the whole time it is plugged in, and simply switch power off to the poweramp to activate the driver...hopefully cutting out the switch noise along the way...got to loose my "pop"...(I think the dual rail design and this BTL amp may also help here) As for construction...saw blade cores (about 1mm thick) spanning the width of the pickup with grooves on either end to take the coil (about 3mm thick) and probably curved across the top. I will paint these cores with nail varnish to prevent rust and insulate them, plus some tape on the ends to prevent the blade cutting into the inner windings. Five of these ceramic craft magnets (A$2) fit nicely but at 12mm round, will take up a bit of depth so am still looking for smaller ones to make it a little more compact, without getting exotic or expensive...rectangular ones would be better. As for the bobbins...not sure, could make something like Tim's jig to make bobbinless coils, but not sure about winding in epoxy. I may well use one pack polyurathane varnish to pot them as I go, I have been using this on some furniture work lately and as long as it doesnt eat the wire's enamel coating, this could work well as an alternative. Otherwise, PVA. The whole thing will probably be set in epoxy anyway once it is finished and painted up. If the device can be made small enough, I may use some metal on the sides as well as some additional magnetic sheilding...this would be unmagnetised. The base plate for mounting will likely be aluminium strip If all goes well with this scheme, I may well add an LED to the side of the driver (between the coils) facing the player to indicate it is working and possibly a momentary tactile switch on the other side so that you can sustain a note at will by pressing a finger to the side of the driver (this may have to wait till version 2). I may even do the whole thing up with an aluminium or SS top to match the chrome look of this hot rod guitar and ward off pick attack, or perhaps simply painted black to match the pickups...I have a spare black SC cover, but it may be that the driver won't quite fit in there to make it look "stock"...plus, the top would need to be cut out of it to accomodate the rails anyway... So that's the overall plan...I've had a bit of flu lately too (know how you feel A) and been a bit busy with everything (got promoted at work), but I'm getting the "bug" back now, so a little mucking about with this is probably good therapy at this point... pete Link to comment Share on other sites More sharing options...
donbenjy Posted June 2, 2007 Report Share Posted June 2, 2007 wow! I like the saw blade core idea! Why's there 4 blades on juan's design though? it's not a quad winding right? It looks as if I can't get into my P90, so I'm gonna have to seriously consider a mid driver anyway, so I may as well try, as long as 0.20mm wire is still ok to use? The AWG and SWG codes aren't meant to be easy to understand are they?! Not poked at my F/R since my last post, but I think I'll try to construct a saw-blade type dual driver anyway....the core for my single driver was a HUGE am antenna from a radio (plus I split it in the wrong place with a chisel :S) so I wasn't really happy about winding onto it. My first attempt is probably gonna be stupidly too big, but I can try! Link to comment Share on other sites More sharing options...
mrjstudios Posted June 3, 2007 Report Share Posted June 3, 2007 I experimented with coping saw blades -- they do work well. I just prefer a 3mm thick piece of bar stock steel since it is not flexible (even lengthwise) at all. Also, the bar stock is not "hardened" or heat treated like a saw, and it sure seems to be more magnetic, but I have no way to measure or prove that.... Anyway, I'm definitely going to try one of these dual rail drivers, but first one question: Can a dual rail driver be easily made as about the size of a single coil pickup? I'm not sure about their actual size in the previous pictures, but I want mine no wider or taller than a strat pickup. I hope this is possible, and not just a HB sized design..... Also, regarding shielding: I am really getting into this whole magnetic shielding business, since EMI is never going to be completely eliminated no matter how good these things get. I would like to know what has worked for some of you. I was thinking Aluminum is the idea substance since it is not magnetic, is lightweight, and very easy to work with. I have rolls and rolls of sheet Aluminum that is about 0.5 - 1mm thick, so I will use that to layer in my shielding work. My new design idea came from the fact that I need to sandwich 3 sheets of the Al together to get a good thickness; I figure that there must be some substance or field that we can create or put in between the Al to make a nearly EMI proof shield. I'm currently researching EMF Shielding and what places like FermiLab use to contain huge EM fields. Hopefully there is a simple polymer or non-metal film that could be glued inside the Al to create a better barrier. By the way, does anyone know how computer speakers are actually EM shielded so well? And why that technique can or can't be applied to a driver? Between you guy's huge steps in cutting EMI at the driver, the slight changes in the circutry to eliminate EMI from there, and maybe a better EM shield, maybe we could really get to the point of a no-feedback (with pickups) and low-noise driver system. -MRJ STUDIOS Link to comment Share on other sites More sharing options...
donbenjy Posted June 3, 2007 Report Share Posted June 3, 2007 hmm...I had an iunteresting musing over a bobbinless, but less messy driver, but I might be completely short of the mark here! If your core is thin enough (like a saw blade) take a suitible drill bit roughly the size of the depth of the core, and drill into the blade. Then you'll get a kinda of double ended "spanner" shape, kinda like the angling found on tuners, that force the string down into the middle. This will cause the windings to be pushed inward at each end, so providing you wrap tight enough, then it should work well. It does mean that the windings will be more dense around the centre of the core, rather than spread across the depth, but providing you can get the hole deep enough into the blade, you'll have no protrusion at each end of the core. Obviously it'll need to be ironed out, but is it feasible? Link to comment Share on other sites More sharing options...
psw Posted June 3, 2007 Author Report Share Posted June 3, 2007 Ahh...questions and ideas... donbenjy...yes, this idea of drilling seems to be the way that juan may have made this driver...real details are a little scketch, if you go back to that part of the thread (using the pink arrow in the quote) you may find some more thoughts about it... The idea is similar to that in the sustainiac/hoover patent, though not how they actually make their drivers...and a few others too...I am not sure if this is really the best approach as it will coause bulging that can only add to inefficiency. Better to file out the roundness...or as I propose, use an angle grinder with a blade about 3mm thick to cut slots... mrjstudios I experimented with coping saw blades -- they do work well. I just prefer a 3mm thick piece of bar stock steel since it is not flexible (even lengthwise) at all. yes...a good point...the steel from computer caseings may be a better material...all a matter of experimentation and what is at hand. I used ordinary 3mm steel to great effect and found it easy to work with and cheap to buy...unfortunately, for an SC sized rail, they will be a little too thick I fear, especially for parallel coils of up to 16 ohms each! I have an idea of solid temporary bobbins that the blade slots into, cut with itself for a perfect fit, that will hold the coil in tight while winding and potting and keep the blade stable while winding...a variation on Tim's winding jig in many ways... Can a dual rail driver be easily made as about the size of a single coil pickup? For sure it can. But a neat assembly is the key. My concern is that without making one of these coils, I won't really no the dimensions required to make it happen. Depth of coil and such to accomodate the windings. As always, it may take a few goes to get it right...then we can all know. I think a very thin core is important for this size of device, and the saw blade idea...or something similar (I have other ideas if this proves to be a little difficult to work). Look at a rail pickup for a guide to dimensions. I think a single coil sized HB driver has advantages over a full sized HB, though possibly a little more difficult to make. I am really getting into this whole magnetic shielding business, since EMI is never going to be completely eliminated no matter how good these things get. I would like to know what has worked for some of you. I was thinking Aluminum is the idea substance since it is not magnetic, is lightweight, and very easy to work with. I have rolls and rolls of sheet Aluminum that is about 0.5 - 1mm thick, so I will use that to layer in my shielding work. Hmmm...I think you are barking up the wrong tree here...it is precisily because it is not magnetic (actually slightly anti-magnetic, but generally modeled as an equivilent of air) that it has no benefit against magnetic interferance. Similarly copper, and other good conductors have no magnetic qualities that aid in magnetic (electromagnetic, or otherwise) sheilding. You could however make a kind of active electromagnetic shield via a coil of opposite electromagnetic force, but then that is why we are favouring the rail design in the first place. If used purely as a sheild...say a coil wrapped around the whole device generating an opposite EMI effect...you would still need to power the thing, which could be excessive without influence on the vibration on the string....the purpose of the device. Such a shield may also generate it's own signiture EMI as well, causing yet another source of EMI, regardless of the other factors I have mentioned... I figure that there must be some substance or field that we can create or put in between the Al to make a nearly EMI proof shield. Well...you could encase the entire thing in steel, trapping all the electromagnetic energy within...problem is that the EMI is what makes the string vibrate...you want it to get out...but not into the pickups! Once the electromagnetic energy is effecting the steel string, it is not hard to imagine how it can travel along this "magnetic conductor" and be sensed by the sensitive magnetic pickups in a guitar. By the way, does anyone know how computer speakers are actually EM shielded so well? Not precisley, but with a speaker you don't hear the electromagnetic energy...but the vibrations of the air molecules excited by the speaker cone...we are using a similar effect here, but working directly in the electromagnetic realm, so we don't have the option of completley encasing the device to trap EMI (or it wouldn't work...seee above). Bit of a conundrum I'm afraid...but an intriguing mind game that I have and will continue to play I imagine... Between you guy's huge steps in cutting EMI at the driver, the slight changes in the circutry to eliminate EMI from there, and maybe a better EM shield, maybe we could really get to the point of a no-feedback (with pickups) and low-noise driver system. I think we may already be there...I certainly hope so! It is simply a matter of putting in the hours, as Avalon and Juan has done) to detirmine the most likely way to proceed. The answer will seem rediculously simple once it is revealed, I believe. For instance...the "thin driver concept" of mine developed from my hex designs. These radical devices became ever smaller but exploited everything I could think of to limit EMI or at least use EMI effectively to drive the strings and to "balance" the electromagnetic forces (including 12 high powerded magnets!)...but the real breakthrough, was that the major contributor to their performance was not so much these novel elements but their small size. The "thin driver concept" entails that the forces are optimised as close to the string as possible and their size also limits the EMI to as small a space as possible...simple, small size, small area of stray EMI. Combine this with a dual coil system that balances the output of one coil with a similar but inverted output from another, and you have quite a powerful concept, yet simple. To this you could add steel to either side in an attempt to keep the EMI close to the driver...but then, do we have the space for that, and is it really necessary if what we are using is enough for our purposes? There are always improvements that can be made, but these will be done by actual construction at this point, and the sharing of these experiences...we will look back and wonder why we didn't do these things in the first place, but let's not ignore the effort it takes to get to that point, and the many mistakes and blind alleys we will be forced to make and follow. We sould all be proud of how far this has come and what has been achieved bit by bit, I think we have done some inovative work and developed working devices that come very close to what we intended to do, perhaps even surpassed that...and I am sure there is still more that will be achieved. If nothing else, we have had the opportunity to exercise our minds together and meet over these ideas...that in itself is reward enough... pete Link to comment Share on other sites More sharing options...
Avalon Posted June 3, 2007 Report Share Posted June 3, 2007 (edited) Anyway, I'm definitely going to try one of these dual rail drivers, but first one question: Can a dual rail driver be easily made as about the size of a single coil pickup? Yes, here another pic of my dual rail next to a 9v battery (which i should have had in the pic in the first place lol): This was made with 2mm cores, and 0.20mm wire (SWG 36, AWG 32), it doesn't quite fit in my single coil cover, but its more then small enough to actually fit in a single coil size hole on a guitar. My next version is going to be bobbinless, on 2mm cores, with 0.18 guage wire (SWG 38, not sure what AWG that is), but the 0.18mm wire reduces the mass of the coil, and lowers the amount of turns needed, which together saves alot of space and has already been fully tested on my fullsize humbucker, that is working brilliantly. You can see from the pic its already quite compact, and that one is a bit of a butchers job, the mark 2 will be far neater, smaller, and as effective, the real trick will be getting it to work in my AV-1 guitar mid position, which may as yet prove near impossible, but on a strat type guitar, i think its a good design. Edit:Should also just add that my dual rail is 2x13.5ohm (3mm high)coils wired in parallel, where as my fullsize humbucker driver, is 2x16ohm (2mm high) coils wired in parallel, and that the Fullsize humbucker coils are still smaller then the DR. Edited June 3, 2007 by Avalon Link to comment Share on other sites More sharing options...
donbenjy Posted June 3, 2007 Report Share Posted June 3, 2007 Ahh...questions and ideas... donbenjy...yes, this idea of drilling seems to be the way that juan may have made this driver...real details are a little scketch, if you go back to that part of the thread (using the pink arrow in the quote) you may find some more thoughts about it... The idea is similar to that in the sustainiac/hoover patent, though not how they actually make their drivers...and a few others too...I am not sure if this is really the best approach as it will coause bulging that can only add to inefficiency. Better to file out the roundness...or as I propose, use an angle grinder with a blade about 3mm thick to cut slots... Yeah, I thought that bulging may be a problem, though I have no idea what kinda of effect it would have. I initially started thinking about cutting slots, but then I don't have many heavy duty power tools around, so unless I can work on it with a friend who does, then I'm gonna have to use a heavy duty drill bit to cut my blade. I don't really want to use a bobbin, because It'll add lots of excess bulk, and I don't want to deal with the issue of getting the width right to accomodate the windings without using extra space. The idea of just the blade means that the driver will be the smallest possible for the depth of the core, as it's only the windings that take up space. Ultimately, I'll probably use a single coil casing with the top chopped off, although I really like the idea of using a Tele style lipstick cover. Not too sure whether this too, would be magnetised. Can parellel coils use the same magnet, or are is one of them connected "RWRP" style for "humbucking?" (I.e. connected out of phase, but with an opposing polarity magnet, so the flux is still directed in the same direction) Link to comment Share on other sites More sharing options...
Avalon Posted June 3, 2007 Report Share Posted June 3, 2007 Well my Dual Rail has just the one magnet, 1 pole on the top core, 1 on the bottom, my fullsize humbucker has two magnets though, but still both cores on opposite poles, which is quite important, i tested them on the same pole, and they're not as effective. Link to comment Share on other sites More sharing options...
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