col Posted March 17, 2007 Report Share Posted March 17, 2007 THANKS COl-- Good -- I'll use the 30AWG then. The driver coil depth IS 6mm instead of 3mm, so I hope that's ok as well. hmm, 6mm may not be optimum. Pete always talks about a 'thin' driver, But I have another theory about why 3mm is ideal for the driver coil depth. Its because for the coil to work most efficiently, there should be as much close interaction between as many of the turns of wire as possible.... if its tall and narrow, the windings are spread out, if its wide and flat, they are spread out... but you will see that for 0.23 wire wound around a pickup length core, 3mm depth gives you about 3mm width for the wire bundle cross section. basically, we want that cross section to be roughly square. What kind of glue should be used for keeping the wrapping wire in place / potting it? Is Elmer's wood glue ok? I used epoxy so did Tim, Pete used PVA (Elmers is pva right?)... search the thread for pva and epoxy, theres plenty of discussion. (look near the bottom left of a page to find the 'search this thread' option. Also-- since I am using an old single crap 'o' caster pickup as the sustainer -- will it work using the existing 6 poles, magnet, and now blocked up to 6mm bobbin? It should work - better blocked to 4mm or 3mm though if possible. cheers Col Link to comment Share on other sites More sharing options...
FlashBandit Posted March 17, 2007 Report Share Posted March 17, 2007 (edited) col, thanks for your reply, it really helped. Seriously, I'm a noob at this, thanks. In the interim time though, I've come across a few more questions, if you have a minute: On the Fetzer/Ruby schematic, the 9v batter has the positive terminal attatched to stuff, but what about the negative terminal? Does it attatch to ground? And same thing goes for the input, do I need to account for the ground for that? How do you divide the bridge pickup signal so that it drives the driver and plays through the amp? When you coil the driver, does each loop have to lay perfectly to the side of the previous one, or can you just wrap it really fast? And lastly (I hope), you substitute the speaker in the schematic for the driver, right? which end of the driver is +/-? Thanks again. Edited March 17, 2007 by FlashBandit Link to comment Share on other sites More sharing options...
mrjstudios Posted March 17, 2007 Report Share Posted March 17, 2007 Thnks Again Col! If I understood you right, about the coil cross section, you mean that the distance of bobbin left unblocked (6mm for me), should be equal to the distance from the bobbin to the last strand of wire measured horizontally, so that if the coil was by itself, the bundle of wire cross section would be the same diameter from any angle? (I'll post a diagram to show what I'm talking about.) My blocked bobbin is 6mm open for winding, and is 4mm deep, so the crossection is 6mm x 4mm, which is not square. However, I think, from what I've learned in physics, that it shouldn't matter much since the equation for a magnetic coil is (Magnetic Field Strength in Tesla) = # Turns [(2pi x .0000001newtons per cross sectional area of the wire x Current in amps) / radius of the COIL] or B = (N) [(2 x pi x K x I) / r] There is no mention of cross sectional area / position in this eq, so theoretically, a slight variation in cross sectional position should have a unnoticable effect, if any. However, the equation for a solenoid is the same as above except replaces the radius of the entire loop with the length of the solenoid, (which could represent blocked up bobbin length) and the 2 with a 4. So if the sustainer is a solenoid, not just a 'loop' or 'coil', it is possible that the length would slightly reduce power on the magnetic field. If someone could find me the exact amps running through the sustainer -- I should be able to find an 'optimum' cross sectional situation, or see if it really matters at all. About the ex-strat pickup -- mine has the varying lengths of poles -- the center 2 are the highest, the outside 2 are lowest. Is that a factor? Thanks in advance!! Link to comment Share on other sites More sharing options...
mrjstudios Posted March 17, 2007 Report Share Posted March 17, 2007 Also -- ELMERS GLUE IS PVA GLUE!!! YAY!!! I wonder though, which should I use -- regular elmers white glue, or elmer's wood glue? Link to comment Share on other sites More sharing options...
col Posted March 17, 2007 Report Share Posted March 17, 2007 Thnks Again Col! If I understood you right, about the coil cross section, you mean that the distance of bobbin left unblocked (6mm for me), should be equal to the distance from the bobbin to the last strand of wire measured horizontally, so that if the coil was by itself, the bundle of wire cross section would be the same diameter from any angle? (I'll post a diagram to show what I'm talking about.) My blocked bobbin is 6mm open for winding, and is 4mm deep, so the crossection is 6mm x 4mm, which is not square. However, I think, from what I've learned in physics, that it shouldn't matter much since the equation for a magnetic coil is (Magnetic Field Strength in Tesla) = # Turns [(2pi x .0000001newtons per cross sectional area of the wire x Current in amps) / radius of the COIL] or B = (N) [(2 x pi x K x I) / r] There is no mention of cross sectional area / position in this eq, so theoretically, a slight variation in cross sectional position should have a unnoticable effect, if any. However, the equation for a solenoid is the same as above except replaces the radius of the entire loop with the length of the solenoid, (which could represent blocked up bobbin length) and the 2 with a 4. So if the sustainer is a solenoid, not just a 'loop' or 'coil', it is possible that the length would slightly reduce power on the magnetic field. If someone could find me the exact amps running through the sustainer -- I should be able to find an 'optimum' cross sectional situation, or see if it really matters at all. (disclaimer - I am not an expert, I'm barely a beginner ) Basic solenoid equations only work for solenoids long enough to ignore fringe effects... so not a sustainer driver... also the extremely non-cylindrical shape of the coil is likely to have an impact. The driver coil has a soft magnetic core so any useful equation would have to take into account the permiability of this core material... also the gap between core and coil is crucial... (a suitable core can amplify the field up to 1000 times!!) Afaik (can't find a reference right now) the equations for a multi-layer solenoid are more complex than those for a single layer solenoid.... which would suggest that a change in the cross section aspect ratio would have an effect - as your coil gets longer and thinner it becomes more like a single layer coil... The technical term (I think) is 'coil density' for a single layer solenoid it basically comes down to turns per metre, but for a multi-layer, I guess there are a number of factors - winding pattern, thickness of the wires insulation, how tightly wound the coil is(important one for us diy driver builders) whether extra insultaion is used between layers as in some transformers... Maybe this effect is only significant when a core is used.... Or maybe the place where I read about this was not a reliable source I'll keep looking for answers... About the ex-strat pickup -- mine has the varying lengths of poles -- the center 2 are the highest, the outside 2 are lowest. Is that a factor? Thanks in advance!! Maybe thats not the best pickup to choose ? certainly if any 2 strings are going to be furthes from the driver it should be the D and G strings - those are the ones that seem to be easiest to drive... also the B and particularly high E strings should be as close as possible to the driver... Can you swap the pole pieces around to accound for this ? cheers Col Link to comment Share on other sites More sharing options...
psw Posted March 17, 2007 Author Report Share Posted March 17, 2007 Yay...we are all on the same page now...mrjstudios, glad you found the thread...and welcome too to, FlashBandit !!! Ok...the thin driver...reasoning 1. have tried other schemes with less to little effect...4mm was ok though... 2. as col has suggested, the number of overlapping wires is a major contributor to efficiency... 3. by being thin, you have the coil all on one end of the magnet/core polarity, not spread over the magnet's length (so both north and south) possibly cancelling out some of the effect... 4. you have the whole coil right under the strings for maximum effect 5. you limit the size, thereby limiting the EMI window effecting the interactiion with the guitar's pickup... 6. other benefits such as putting the coil on top of a pickup or next to it on the surface of some guitars... a few potted questions...got to run... Also, about how many wraps gets you to 8 ohms? over a hundred, less than 200...you really need to measure it but if it is a little less or over it souldn't matter too much... What gauge wire should I use? 0.2mm enameled wire. A small reel could hold 25M and will wind several complete drivers at a cost of about A$7 down here. How can I test the amp before making the driver to know it works? connect a speaker to the circuit instead of the driver and the thing should work like a little practice amp. When you coil the driver, does each loop have to lay perfectly to the side of the previous one, or can you just wrap it really fast? It shouldn't take too long to wind a hundred turns or so, perhaps 10 minutes to do it neatly. But no, you wont get it so neat that it doesn't cross over or there aren't some loose bits at the side that need to be pushed into the glue and wound over. It may even be possible that some of this scatter winding is beneficial. Don't attempt to use some kind of machine and do take a bit of time and attention on it...it really isn't that hard, it's kind of fun...but don't forget the glue and be prepared for a little mess. Also, have all you need at hand before you start, see the pictorial in the link below to see how I did it. I would still advise against epoxy if winding onto a bobbin and the white glue seems to function ok...wind over tightly with electrical tape cut to the appropriate width (3mm strips) to keep it all together while the glue dries and you are ready to test it... It is possible to test it from the output jack but the pickup is best connected before the controls. In my guitar, the pickup is connected to the circut and the continues on to the controls and then the amp as usual. both the hot and ground/earth leads of the pickup signal wires and the -ve lead of the battery are connected to the ground rail of the circuit. With an actual installation, you need to make the bypass switch completely disconnect both the hot and ground leads of the unused pickup coils...but I would not worry about this and other installation issues until after you have proved that the device is working.... And lastly (I hope), you substitute the speaker in the schematic for the driver, right? which end of the driver is +/-? It doesn't matter as one way will be the harmonic mode the other normal and you will want a switch to reverse them anyway eventually to switch between these modes (in testing, just switch the wire and pull the battery to turn off!). With a speaker, it will sound the same... Anyway, hope this answers a few of the questions put here and I wish you every success... pete Link to comment Share on other sites More sharing options...
mrjstudios Posted March 17, 2007 Report Share Posted March 17, 2007 Here it is with the coil removed (ready for rewinding and glueing). The blocked bobbin allows 6mm for winding. How is the setup so far? Link to comment Share on other sites More sharing options...
psw Posted March 17, 2007 Author Report Share Posted March 17, 2007 ahh...pictures really help... ok...I'd suggest giving it a go with wood glue...at worst you may need to remove the wire and block it up some more... I should also say, as these pictures have reminded me, that the core of my driver is only 3mm wide which gives me more space to make my thin driver...your core (the magnets and bobbin) are perhaps twice the width meaning less turns but longer...there is a bit of discussion about the width of the coil, but I do know it works... You may need this extra depth, but I suspect that you could get it thinner with 0.2mm wire... Anyway, give it a go and see... pete Link to comment Share on other sites More sharing options...
FlashBandit Posted March 17, 2007 Report Share Posted March 17, 2007 psw, thanks alot. That was so thorough, and helped alot. Thanks a ton. Link to comment Share on other sites More sharing options...
mrjstudios Posted March 17, 2007 Report Share Posted March 17, 2007 Well, I decided to build a new one for now -- with a solid iron core (custom made) so that I can get the 3mm bobbin you were talking about. The core sticks out of the top, and the magnet is superglued under the core (inside the bottom piece of plastic). I'll use some wood glue and wrap it once the superglue dries. (Elmers wood glue IS PVA) Solid core is better than poles, correct? By the way, here is my custom and still unpainted or finishing sanded guitar.... Plays great though. THANKS!!!!! Link to comment Share on other sites More sharing options...
FlashBandit Posted March 18, 2007 Report Share Posted March 18, 2007 What kind of magnets should you use for the driver? I got six 1/8" neodymium magnets (from radioshack), they're tiny but I've heard they're powerful, would they be powerful enough? I haven't used them yet though. I was thinking about putting the magnets on top of the iron core so they're up close to the strings. My theory was that if I had six small pole pieces located up by the strings, they could help focus the field at each string, but I've seen most people using blade type cores and the long black type of magnets without any pole pieces. What would be best? Link to comment Share on other sites More sharing options...
psw Posted March 18, 2007 Author Report Share Posted March 18, 2007 Looking good there... Solid core is better than poles, correct? with poles there is a little loss of power when bending the strings, hence the blade idea...plus it is easier to make unless you already have a pickup to modify or something...at least it was for me... I actually find I use the trem a lot more with the sustainer guitar for string bending (mine floats a bit) as you can here on tracks like beckistan. So much so, that I am thinking of making a pole version next that will look like a conventional pickup... I got six 1/8" neodymium magnets (from radioshack), they're tiny but I've heard they're powerful, would they be powerful enough? Too strong...at least for the top of the blade under the strings...way too strong. They could be used for a thin blade below...it did work for me below a 3mm driver, but the ceramic magnet did work better. Neodyminum magnets are amazing things but it is tricky to get the application right...they are very powerful but physically very small, I estimate that these tiny 1/8" have as much power as a whole alnico strat pole, but all that power under the string is way too much. The other thing is that the opposite pole, N-S, is in very close proximity so it is attracted very strongly to itself...odd things indeed... If you can get a pickup magnet that is ideal. I have seen small craft ceramic magnets for a couple of dollars that would work, recently I found some in a bargain shop which could double as the core potentially, making for a very compact stand alone driver. I know this is the kind of thing that Tim is interested in, and looking at my new guitar, I see that there would be plenty of room for such a device next to the neck pickup below the strings, stuck to the surface of the guitar. Such an arrangement was the impetus behind the box idea, but with a multi pickup guitar, you still need to address the bypassing that requires a total rewiring so the idea, although attractive, still has some major problems with it... Anyway, good to see some new ones being attempted... pete Link to comment Share on other sites More sharing options...
Franky Posted March 18, 2007 Report Share Posted March 18, 2007 (edited) I picked up a magnet from an old pickup, its size is 55mm long, 6mm high and 5mm wide, can I use it as a core? Hum and I wondered if I could use epoxy plate coming from a copper plate (to make PCBs), without copper obviously, to make the top an bottom plates (instead of a CD case, that i've got some problems to work on...) I found some 0.2mm enameled copper wire: http://www.wires.co.uk/acatalog/offers.htm...BR_2d0200_2d050 Edited March 18, 2007 by Franky Link to comment Share on other sites More sharing options...
zenabipxr5 Posted March 18, 2007 Report Share Posted March 18, 2007 welcome zenabipxr5 just take things one step at a time, the whole thing is pretty cheap and the ideas not that difficult. The circuitry is pretty simple but we really need to get something a little more straight forward organised perhaps. At the end of my post are links to several associated threads here on the sustainer. There is one that demonstates the device in action and two tutorials...check them out then check back on us here...I have recently been answering some questions on some of those threads that may be of interest, but you'll get better service if you return to us here on the main thread. Don't be overawed, it really isn't that hard and is an excellent thing to be involved with if you want to learn a little about electronics and the way things work, especially on the guitar and amplifiers, not just the sustainer... Keep in touch... pete thanks! i dont know why but i registered with the name pxr5, my previous attempt was zenabi but it was taken, but when i log in i have to type pxr5, but when im logged in im called zenabipxr5?? lol anyway thanks for the advice. something has come up at home that means im gonna have to put this on hold for a couple of weeks but i will be back, im fascinated with all this. thanks again for the tips, ive already been to the threads you speak of and read tons of stuff the day i joined here, theres so much help its great, i look forward to getting back here. cheers! Link to comment Share on other sites More sharing options...
mrjstudios Posted March 18, 2007 Report Share Posted March 18, 2007 So PSW, you think my blade setup will work well? Judging by the other ones that "worked" that I have seen in this forum, my blade design should be at least decent.... I'll wind / pot it today since the stupid superglue didn't want to dry and came with basically no instructions. My F / R should be done tomorrow so then I can start testing and wiring that in -- Luckily my 5-way selector switch deactivates the other pickup when I set it on bridge pickup mode (all the way down) so I shouldn't need to do a lot of bypassing. -MRJSTUDIOS Link to comment Share on other sites More sharing options...
psw Posted March 18, 2007 Author Report Share Posted March 18, 2007 anyway thanks for the advice. something has come up at home that means im gonna have to put this on hold for a couple of weeks but i will be back Understand...you will always be welcome...whatever you call yourself!!! Luckily my 5-way selector switch deactivates the other pickup when I set it on bridge pickup mode (all the way down) so I shouldn't need to do a lot of bypassing. Don't bet on it...I found that I had to lift both the hot and ground leads on the neck and mid pickup and select the bridge and turn on the power... It will be interesting to see though, I'd love to be able to do such a thing with my new guitar, but I can see things that will be problematic... Still...don't get hung up on the installation just yet...let's get the thing working. Both blade and pole versions work well but everyone has a slightly different experience and approach to it. I picked up a magnet from an old pickup, its size is 55mm long, 6mm high and 5mm wide, can I use it as a core? There is some debate about the "width" of the core and how well it works. To be safe, perhaps a thin steel blade (mine is 3mm steel) with the magnet stuck to the bottom works well. Be careful that the magnet is oriented with the poles up and down. One benefit of winding on a core is that the magnet can be used to make another driver or to compare drivers, whereas if you make it the core, you are committed to that and if it doesn't work, it may be a little hard to get the magnet out to start again, or to try something else... Hum and I wondered if I could use epoxy plate coming from a copper plate (to make PCBs), without copper obviously, to make the top an bottom plates (instead of a CD case, that i've got some problems to work on...) Sure...I have trouble with the CD case option, it is very brittle. I did have some success with laminating thin card and my present driver is made from very thin plastic from a cheap folder that was easily cut with scissors. Tim and I developed an idea for winding bobbinless coils with a jig, but it needs the use of epoxy and working pretty fast to get it right...probably not a good way to start out... Link to comment Share on other sites More sharing options...
Truth_David Posted March 18, 2007 Report Share Posted March 18, 2007 Hi all, sorry to hijack the post..... I am trying to reach a decision as to how best to route the cables between the project box and the guitar control cavity.... As the guitar in question is my Ibanez, which is very thin bodied, and has a rear routed control panel, this leaves two options: The first would be to adapt the jack recess to accept a plastic plate, like my Strat has - which in the case of the Strat actually replaces the metal jack surround plate, and mounts flush to the body - something which will not be so simple to achieve, as the Ibanez has a carved top. The second option is to adapt the rear control cover to enable passing the cables from there to where the project box will be mounted (temprarily at least) just behind the tremolo bridge. This would necessitate running the cables from behind the guitar, around the side and back to the box.... not the most elegant of solutions, which is why I am asking for other ideas I may have overlooked. In this sense having a Strat type scratch plate with the controls recessed beneath it might make it simpler to have the cables coming out to the box, but the downside of course is having to remove the strings (and in the case of my Stat the neck too, as it has a 22 fret custom neck) each time you need to get at the electrics. Another possibility which seems somewhat wierd is to fit a dual concentric pot to replace the tone pot, and leave the hole through which the cables could be passed. The negative aspect of that is that presently my tone pot is doubling as a push/pull pot which brings in the neck p/up in all positions of the 5-way switch - something which I find really useful. So I would really appreciate your help guys, as I cannot take this to the next stage before coming up with a solution that works for me. I really want to avoid having to customize the Ibanez any further, in terms of routing or drilling holes. Juán and I decided that we would try his own circuit which is based around a 6v power supply, as this is specifically intended for use in the Ibanez, rather than the Strat, which as I mentioned previously already has the RMC piezzo midi system installed with a 9v power supply. That will enable us to use a higher quality circuit than the one he had to opt for in the 9v version which coincidentally arrived slightly damaged. As I have the Strat totally stripped down, and the chances are that the sustainer in its present form will not work with the Fender noiseless p/ups that I ended up installing, due to the altered magnetic field the secondary coils produce, I have pretty much decided that the Ibanez will be the project guitar for the sustainer. Then once that is all installed and seen to be working, I will gig with it in the worship group, then I will turn my attention once again to the Strat which I should have finally finished preparing and modifying, and hopefully by then someone might be able to offer some suggestions as to how to get the 9vcircuits working with the noiseless p/ups. In case anyone is interested in the mods I have been doing to the Strat, I could post links to some in progress photos. Basically though, in a nutshell, I have stripped the finish back to bare wood, done some subtle recontouring of the body, and also (not so subtle) to the neck heel and lower cutaway. I am pretty pleased with the way things went, but getting a perfect finish before applying any preparation to the wood has been very time consuming, as I had to sand pretty heavily in order to get rid of the remains of the original paint, and it left traces in the wood. The problem is that here in Spain, one is severely limited as to the grades of sand paper or wet and dry that one can obtain, so there is a problem in removing the scratches made by the previous least coarse grade I used with the finest grade - there is nothing in between - this is a vicious circle with no obvious solution. I am also looking for a replacement tremolo block for the Strat, as the threads have gone on the original. So if anyone has one for sale, or knows of a reasonably cheap supplier, please let me know. Also, if at all possible, I wondered whether I could fit a tremolo block with a different type of tremolo arm fitting, such as a push fit ot a vintage style bridge plate? I would like a means to avoid the eternal problem with Strat tremolo threads getting worn and winding up with a lousy tremolo that is either too loose or so tight that it is impossible to use. This is the present state of things.... I also intend trying an oiled finish, but being a very light coloured wood, probably poplar or maybe basswood, I am not at all sure how that would work out. But ever since I went to a Rory Gallagher gig (God that shows my age!) and saw one of his guitars with the laquer completely worn off, I always wanted to own a Strat like that...I thought it looked really beautiful. Well given the state of deterioration of the finish on my old Tokai Strat, I decided to go for it. The other problem is that the wood is so soft, that it seems to receive impressions from whatever it is resting upon, so I have had to remove indentations countless times - another vicious circle . The shop where I bought the wood finish assured me that in combination with wax it would harden and protect the guitar. Now I understand the difference between cheap and quality woods. Speak soon, David Link to comment Share on other sites More sharing options...
psw Posted March 19, 2007 Author Report Share Posted March 19, 2007 Ok David...well this is interesting and something I am still considering for similar reasons for my new strat, also with a rear access and no scratchplate.... First though, don't get ahead of yourself. Installation is the final stage that has it's own problems, but more important is that the thing works! Have you got the device working in a test mode outside of the guitar??? I don't see any problem with the noiseless pickups and the sustainer...the bridge pickup on my strat is a stacked design. Only split bi-lateral pickups like that on a P-bass or Z-pickups (pretty rare) really have a potential difficulty as the magnetic polatities are different between string sets... So...the box idea... The first would be to adapt the jack recess to accept a plastic plate, like my Strat has - which in the case of the Strat actually replaces the metal jack surround plate, and mounts flush to the body - something which will not be so simple to achieve, as the Ibanez has a carved top. You could take the cables through the guitar's jack and then plug the guitar to the amp via a secondary plug in the box... Be aware that there are significant problems with the close proximity of some of these cables. The driver leads are afterall an extention of the driver coil and so also gives off EMI and runnning alongside signal leads may cause problems. In my guitar you will see that the driver cables are transferred to the driver through the trem cavity well away from pickups and signal leads. All my signal leads are shielded cable within the guitar too, and I still had some problems... My solution that I proposed was to mount the poweramp portion of the circuit (the lm386 part) as close to the driver withi9n the guitar and work only with low level signal leads from the box... The second option is to adapt the rear control cover to enable passing the cables from there to where the project box will be mounted (temprarily at least) just behind the tremolo bridge. This would necessitate running the cables from behind the guitar, around the side and back to the box.... This is the way I would first approach it, make the modifications with the cover off to be sure it works with the wires hanging out there. Unlike a strat, at least the guitar will be playable in this state for testing. Once satisfied that it works ok...then look at the installation options. not the most elegant of solutions, which is why I am asking for other ideas I may have overlooked. In this sense having a Strat type scratch plate with the controls recessed beneath it might make it simpler to have the cables coming out to the box, but the downside of course is having to remove the strings (and in the case of my Stat the neck too, as it has a 22 fret custom neck) each time you need to get at the electrics. The only need to get at the electronics is to adjust it to the guitar and change the battery. Battery access is the most important aspect as this device does use up power. got to run... pete Link to comment Share on other sites More sharing options...
Truth_David Posted March 20, 2007 Report Share Posted March 20, 2007 (edited) Ok David...well this is interesting and something I am still considering for similar reasons for my new strat, also with a rear access and no scratchplate.... Good idea to put our heads together on this one then First though, don't get ahead of yourself. Installation is the final stage that has it's own problems, but more important is that the thing works! Have you got the device working in a test mode outside of the guitar??? Juán is sending me a prewired circuit from his own project, the 6v version, so provided that it doesn't also get damaged in the post it should work right out of the box.... I don't see any problem with the noiseless pickups and the sustainer...the bridge pickup on my strat is a stacked design. Only split bi-lateral pickups like that on a P-bass or Z-pickups (pretty rare) really have a potential difficulty as the magnetic polatities are different between string sets... That is great news, thanks So...the box idea... You could take the cables through the guitar's jack and then plug the guitar to the amp via a secondary plug in the box... Juán and I are currently investigating the idea of using some sort of computer cable to possibly run via a plug in system on either side of the circuit. Personally, given that the cable is very thin and reasonably flexible, I feel that this might be the most elegant solution. It would also provide a means to plug and unplug between different instruments, in which case only the plug connector need be wired into the guitar control circuit, and the rest could happily stay inside a guitar mounted box. Juán has asked me to post a photo he sent me of his wiring solution: It requires absolutely no complicated switching as it is a physical switch which just takes advantage of the movement of the metal contacts on a Fender type 5 way switch, by supergluing a tiny plastic plate on one contact and the micro-switch on the bridge position contact, and the section of plastic is used to push the micro-switch as the lever is moved to the bridge p/up position. When in that position the micro-switch allows current to pass to the sustainer On/Off switch, thus if the 5 way is not in the bridge position, even though the sustainer is switched on, there will be no current. The other advantage is that the 5 way switch will continue to work as normal with no complicated switching routines to switch pickups in and out of circuit. The downside as far as I am concerned is that the Ibanez is fitted with a different type of 5 way switch that does not have the contacts exposed, being totally encapsulated within a bakelite container. Only the circuit connectors appear in a row on top of the switch: The other possibility of swapping the Ibanez switch for a Fender type on is also out of the question due to the thinness of the body and also the way the switch is mounted through the body using a plastic insert and nuts and bolts. I tried..... So it is looking as though I am going to have to go for the electronic switching option which Juán is dead against, especially when you take into account his brief which was to produce as simple a system as possible. Nuts! Time to get my thinking cap on again!!!!!! Be aware that there are significant problems with the close proximity of some of these cables. The driver leads are afterall an extention of the driver coil and so also gives off EMI and runnning alongside signal leads may cause problems. In my guitar you will see that the driver cables are transferred to the driver through the trem cavity well away from pickups and signal leads. All my signal leads are shielded cable within the guitar too, and I still had some problems... My solution that I proposed was to mount the poweramp portion of the circuit (the lm386 part) as close to the driver withi9n the guitar and work only with low level signal leads from the box... This is the way I would first approach it, make the modifications with the cover off to be sure it works with the wires hanging out there. Unlike a strat, at least the guitar will be playable in this state for testing. Once satisfied that it works ok...then look at the installation options. Can't do that, the case is shielded, and unless it makes contact with the internal grounding circuit it just produces a mountain of hum and noise.... The only need to get at the electronics is to adjust it to the guitar and change the battery. Battery access is the most important aspect as this device does use up power. In my version, the batteries will be inside the project box - Juán's 6v version will run on 4 1.5v batteries, and with luck I will be able to use high amperage rechargable ones like my digital camera uses, and they will possibly last a reasonable time. Another option is a special battery I just discovered in an old cordless phone. I have to check the voltage though, but those are designed to hold charge over fairly lengthy periods. Juán says that the 6v circuit is far less juicy than the 9v versions, and that the quality of the circuits is also apparently far higher and therefore less noisy and with less tendency to produce distortion of the signal. Speak soon, hope things are OK your end Pete, my thoughts are with you as always. David got to run... pete Edited March 20, 2007 by Truth_David Link to comment Share on other sites More sharing options...
col Posted March 21, 2007 Report Share Posted March 21, 2007 Juán and I are currently investigating the idea of using some sort of computer cable to possibly run via a plug in system on either side of the circuit. Personally, given that the cable is very thin and reasonably flexible, I feel that this might be the most elegant solution. It would also provide a means to plug and unplug between different instruments, in which case only the plug connector need be wired into the guitar control circuit, and the rest could happily stay inside a guitar mounted box. That sounds interesting, although I'm a little surprised that you are investigating advanced potentially problematic solutions when you don't have a basic system test done and dusted... how do you know what will happily stay where - this isn't a 5mA stomp box, it pushes much higher level signals around - the connectors will radiate a lot of magnetic radiation, so they are critical to the success of the device - PLEASE get a basic test done before dismissing the existing solutions. Juán has asked me to post a photo he sent me of his wiring solution... Thats a really cool idea - ingenious. Its a shame that its strat specific - but great for all those strat users anyway So it is looking as though I am going to have to go for the electronic switching option which Juán is dead against, especially when you take into account his brief which was to produce as simple a system as possible. Nuts! Time to get my thinking cap on again!!!!!! Again I say - get a basic system up and running before making these kinds of decissions. You are talking about a major design decission for a device that you have not even tried yet !? Remember that you do have choices: #1 try and design a complex electronic switching circuit that will be a pain to debug (it could have problems related to noise and interference - shared earth issues etc.). It will also take up space in your guitar cavity, and will still need all those wires to be connected. More soldering of wires = more to go wrong and more difficult to debug. #2 KISS - yes, keep it simple... it might be prudent to lower your sights and actually compromise on pickup selection choices rather than having a sustainer device thats so complex - you still don't know what its like to play with - maybe when you've tried a basic version you will get a different perspective ? My solution that I proposed was to mount the poweramp portion of the circuit (the lm386 part) as close to the driver withi9n the guitar and work only with low level signal leads from the box... This is the way I would first approach it, make the modifications with the cover off to be sure it works with the wires hanging out there. Unlike a strat, at least the guitar will be playable in this state for testing. Once satisfied that it works ok...then look at the installation options. Can't do that, the case is shielded, and unless it makes contact with the internal grounding circuit it just produces a mountain of hum and noise.... have you have tested it? Please remember that the suggestion of using an external project box is is really about avoiding guitar modifications while _testing_. For a final installation, there are so many potential issues related to having that box that it just doesn't make sense at this stage. Having the circuit outside of the guitar connected by longer cables will introduce noise and interference, but as it's just for testing, its not so important... When the device is tested and working to your satisfaction, then its time to see how you can get it all into the guitars control cavitie(s) - at this stage, you should ditch the project box... if there is noise, grunge, fizz etc. with everything inside your guitar and with all the cable lengths minimised, then either there is a design problem or something wrong with the construction or layout of the system. Juán says that the 6v circuit is far less juicy than the 9v versions, and that the quality of the circuits is also apparently far higher and therefore less noisy and with less tendency to produce distortion of the signal. That is very interesting fo two reasons: #1 A low powered circuit with better efficiency that still produces the same level of drive would be a big step forward - so that's great news. #2 The circuit that I designed that Juán tested and rejected doesn't produce any noise or distortion of the signal. I am now even more interested in hearing some demos of this system, just to assess this "tendency to produce distortion of the signal" (I hope it's just something that didn't translate). I really hope that Juán has made improvements, but there are some important points: * For DIY reasons, it must be possible to build the circuit from readily available parts without having to deal with PCBs or SMD devices. * There must be no sustainer noise (or grunge/fizz/fuzz) in the guitar output - this is very important - and it's _much_ easier to create a high performance AGC if you ignore this one That said, I find that for some applications, my setup responds slower than I would like, it would be nice to have more control of the dynamics of the AGC, so if one of the on chip AGC devices can fulfill all the other requirements, I am eager to try it. I wonder if Tim has got around to building an AGC circuit yet? cheesr Col Link to comment Share on other sites More sharing options...
onelastgoodbye Posted March 21, 2007 Report Share Posted March 21, 2007 I wonder if Tim has got around to building an AGC circuit yet? yes I have, but haven't been able to test it yet as my guitar is currently 'under construction'. I have aquired a bunch of 2 x 2 neodymium magnets as well, so i can get cracking at a side driver. Still have to figure how the configuration of the magnets will be as they have pretty weird magnetic behaviour, and they're probably too strong right under the strings; maybe 2 per string with N-N facing eachother and the string in the middle? Link to comment Share on other sites More sharing options...
mrjstudios Posted March 21, 2007 Report Share Posted March 21, 2007 2 neodymiums per string?!?!?! Wow, they'd probably pull the strings right down onto the sustainer. Also, if you mount them (N-N) with neither of the poles facing directly up, your mag field will be very oddly shaped in relation to the strings -- but hey, maybe the odd shape would create something new. A magnet with the poles running parallel, instead of purpendicular (like in all pickups and sustainers I've seen), could make one unique pickup or sustainer! Link to comment Share on other sites More sharing options...
FlashBandit Posted March 21, 2007 Report Share Posted March 21, 2007 (edited) <REMOVED> I found most of my answers. Edited March 24, 2007 by FlashBandit Link to comment Share on other sites More sharing options...
JoeUK Posted March 22, 2007 Report Share Posted March 22, 2007 I remember someone mentioning the use of magnets from computer hard drives for the driver. I pulled an old hard drive apart and got 2 of these [url=http://s132.photobucket.com/albums/q21/ukaxer/?action=view¤t=HDiskMagnets.jpg] bits of metal with the 2 'kidney shaped' magnets on each. I dont know what type of magnets they are, but they seem damn powerful - 1 set of magnets will move the other set from about 2" above, and when attracted together, it takes a fair amount of pulling to get apart. Q's 1. Any good for the driver? Bearing in mind Pete's warning about about trying to cut certain magnets - 2. can I prise them off the metal? 3. can the magnets be cut or shaped to better fit under the driver (without me spontaneuosly combusting)? 4.AM I barking up a gum tree? Ive also found some fridge magnets backed with the flexible magnetic strips and 3 small solid circular magnets (about 8mm across + 3mm deep), used for 'sticking' notes etc. to metal boards. Any of the above good for the driver + which would be more advisable? Cheers Joe Link to comment Share on other sites More sharing options...
col Posted March 22, 2007 Report Share Posted March 22, 2007 I remember someone mentioning the use of magnets from computer hard drives for the driver. I pulled an old hard drive apart and got 2 of these [url=http://s132.photobucket.com/albums/q21/ukaxer/?action=view¤t=HDiskMagnets.jpg] bits of metal with the 2 'kidney shaped' magnets on each. I dont know what type of magnets they are, but they seem damn powerful - 1 set of magnets will move the other set from about 2" above, and when attracted together, it takes a fair amount of pulling to get apart. Some sort of rare earth - either neodymium or the other type (can't remember the name) Q's 1. Any good for the driver? dunno, although the shape doesn't look ideal - you also could have done with something in the photo for scale... e.g. a plectrum... Bearing in mind Pete's warning about about trying to cut certain magnets - 2. can I prise them off the metal? 3. can the magnets be cut or shaped to better fit under the driver (without me spontaneuosly combusting)? 4.AM I barking up a gum tree? be careful - definately wear safety glasses ! I think pretty much all magnets apart from the crappy plastic ones nead special tools for successful cutting - even if you cut them to the size you want, you might damage or destroy their magnetic properties Ive also found some fridge magnets backed with the flexible magnetic strips and 3 small solid circular magnets (about 8mm across + 3mm deep), used for 'sticking' notes etc. to metal boards. Any of the above good for the driver + which would be more advisable? [/qoute] Ah, the crappy plastic ones the problem with (most of ?) the plastic strip/sheet is that it has a wierd pole arangement with alternating stripes of NSNSNS, no good for a driver... even if the poles were good, they may be too weak anyhow. And most likely the field will not be very predictable or even (just guessing here). have fun cheesr Col Link to comment Share on other sites More sharing options...
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