col Posted November 17, 2006 Report Share Posted November 17, 2006 It would be one thing to be able to shrink this circuit down enough to fit into a guitar and then find room for a battery...tricky... Unfortunately, it is going to be rather large unless there is at least a pcb for it - preferably with SMD parts. Right now I'm working on a stripboard layout for everything but the LM386 section. It uses 3 dual op-amps and at this stage is 26 x 18 holes of board. It's fairly well optimised, so I doubt it could get a lot smaller without at least going to 1 quad + 1 dual amp - even then, it's going to be quite large. No problem for me - but not easy if your axe has a small cavity. One idea I alway seem to come back to is those battery boxes that install in the back and flip open...perhaps you could route it a little deeper and put the circuit behind it, or perhaps the switches... On multi pickup guitars you do have the bypasing issues too...that means a pretty big switch body in the control cavity or wherever at the very least... I did discover some interesting switches at one point that were probably made for computers. These are latching 4pdt pushbutton switches with a clear top that illuminate as well...pretty small and mont vertically (deep) which are interesting...Altronics switch...I actually bought a few in different colours and they seem sturdy enough...at $2.95 they are certainly cheaper than a toggle, but whether they would be more convieniant, I'm really not sure...and then you'd have to mount them in some way....hmmmm If we do get to the SMD stage, it would make sense to use some switching chips to alow for simpler smaller hardware... otherwise everyone will have to decide where the best compromise for them is... depending on the space they have and their setup, some might opt for no harmonic mode malarky, others may have to stick with the basic fetzer/ruby. It is amazing the quality of some cheap guitars these days...the guitar I saw was a new squier strat with 2 post trem and duncan "designed" HB pickup, 22 frets and top loaded pickups (no scratch plate) for a little over A$300, out of indonesia... looks nice - mind you, if I was buying a strat, I'd want 3 single coils.... I guess you need a humbucker though What I really want is a 3 single coil guitar with 24'' scale - maybe a mutant mustang type of thing. I like the Brian May sound, and he used a 24'' scale. I don't have big hands, and the smaller scale would make many licks and scale shapes more accessible. And of course, in addition to that, you can imagine that a sustainer would work much better with the lower string tension that 24'' scale provides. cheers Col Link to comment Share on other sites More sharing options...
bancika Posted November 18, 2006 Report Share Posted November 18, 2006 Hello, can someone tell me how to determine magnet polarization, how should I place when winding coil. I'll do one driver wound directly to magnet I have, it's 5x6x60mm which should be good. Link to comment Share on other sites More sharing options...
psw Posted November 18, 2006 Author Report Share Posted November 18, 2006 You can use a compass which will point to the Nth polarity. Otherwise, any magnet which you know the polarity, or at least which side is up can be used to tell which side of the magnet is a pole (it will stick or repell). If you don't have another magnet handy...a single coil pickup will have one polarity at the top...usually north...the side that sticks to the pickup will be south. It does not matter if the driver is pointing north or south...just that a pole is facing up (at the strings). This is for a single coil type design. A Humbucker (which this magnet may well come from) is magnetised from side to side so that each coil core is of a different polarity. It is important to check magnets so that you know which side is up! |-N-|.....|-S-| |-S-|.....|-N-| both of the above are ok |N-S| a coil around this would not work... Hope that helps... pete PS... looks nice - mind you, if I was buying a strat, I'd want 3 single coils.... I guess you need a humbucker though Yes...well I would have to put some serious thought into this. I always played a Les Paul but have big hands and the thing weighs a ton. Since playing strats I find them so much easier and the trem has become essential...influenced by surf, J beck and the shadows I guess...espesially with the sustainer. This guitar is mahogany but with a maple neck and strat conststruction so the sound is still snappy. I am really wary now of guitars with noise problems and the strat is typical. Having a back plate instead and top loaded direct mount pickups would make it easy to work on and change batteries (I would need to enlarge the control cavity though and make a new cover ). You are right though, there is something magical about the single coil sound and splitting an HB will not give it to you... I really like the Dire Straits sound too and ironically, an HB and/or the loss of the mid coil is not going to give me that I suspect. The humbucker would make the mid driver even more difficult to achieve (it is closer due to it's size) but would allow experimentation with this kind of set up... Top mount pickups would make it super easy to exchange pickups if I move into the area of pickup design and making though...could be a great test bench for all kinds of things.... However, there are plenty of fine guitars about at the moment...just window shopping for now. PPS... I hope to be moving next week and am having all kinds of problems with phone services and internet connections. It sounds as if I will be off the air for some time while these things are sorted out. A busy time, so get your questions in while you can...for now it's 5:30am Sunday and time for work...see ya later guys, wish me luck... p Link to comment Share on other sites More sharing options...
psw Posted November 18, 2006 Author Report Share Posted November 18, 2006 (edited) It sounds as if I will be off the air for some time while these things are sorted out. A busy time, so get your questions in while you can... Speaking of which! With a Humbucker in the bridge, is it possible to split the coils and use the coil closest to the bridge as the source for the sustainer but have the full HB as the output for the guitar? There are a few reasons why you may wish to do this. You would get a lower impedance clearer, less hot sound from the single coil into the circuit, it makes the effective source pickup a little further from the driver too. The fact that there is another magnet of an opposite polarity between the driver and the source may also help...especially if that driver (or nearest rail) were of the same polarity (and therefore not attracted to it)... Still, there could be some noise issues...anyone wish to comment on doing this, try it out or otherwise shoot it down in flames!!!??? pete Oh...and this has been mentioned before, but here is a product that will allow for external power through a stereo lead...x-bat Edited November 18, 2006 by psw Link to comment Share on other sites More sharing options...
col Posted November 18, 2006 Report Share Posted November 18, 2006 (edited) Speaking of which! With a Humbucker in the bridge, is it possible to split the coils and use the coil closest to the bridge as the source for the sustainer but have the full HB as the output for the guitar? It's possible. There are a few reasons why you may wish to do this. You would get a lower impedance clearer, less hot sound from the single coil into the circuit, it makes the effective source pickup a little further from the driver too. The fact that there is another magnet of an opposite polarity between the driver and the source may also help...especially if that driver (or nearest rail) were of the same polarity (and therefore not attracted to it)... Still, there could be some noise issues...anyone wish to comment on doing this, try it out or otherwise shoot it down in flames!!!???. Downsides: noise - you lose the noise cancellation in the signal to driver, so I would imagine that the system will become more sensitive to EMI. You don't cancel much fizz - You may remove a little fizz, but if you are using the full humbucker for the output, the full humbucker will detect and output EMI from the driver - I reckon that until you get near to the point of squeal, most of the fizz is this 'primary fizz' as opposed to 'feedback fizz' It may help to reduce sensitivity to the squealing feedback that occurs as the EMI gets stronger, this is where the signal back to the driver becomes more important. However this effect may be nullified by the downside of not having humbucking for the driver signal. And the larger passive magnetic circuit of the humbucker may also lessen any possible advantage. So, it may be slightly better or worse(would be my guess) as far as sensitivity to squeal, but no discernable change in fizz levels. Now we need someone to try it out and prove me wrong - or right. EDIT: Something that might be worth trying if someone does experiment with this approach is to stick a volume pot on the inner coil. It's likely that the inner coil picks up more magnetic radiation from the driver than the outer coil (bridge side), reducing the output from the inner one to the point where the signal level of the EMI is the same from both will improve the humbuckers cancellation ability - so it will become less good at cancelling 'normal' electrical noise, but better at cancelling the localised magnetic radiation from the driver. Of course, if this requires a big adjustment to be effective, then it won't be so useful - we don't want to bring back electrical noise, and lose the tone of the humbucker... but if it only required a small adjustment, it could be a good approach for a permanent installation on a 'sustainer guitar'. Thats assuming it works AT ALL - but IF it does, it may be another step towards realising a middle position driver (with bridge and neck humbuckers). So... has anyone tried a sustainer using a stacked humbucking pickup in the bridge position and compared that with a traditional humbucker ? I wonder if that might be the best type of pickup to use.... a strat with Kinmans in the bridge and neck and a sustainer in the middle ? !!!! hmmmm... Col Edited November 18, 2006 by col Link to comment Share on other sites More sharing options...
col Posted November 18, 2006 Report Share Posted November 18, 2006 So, I decided to see how things are like in the middle position with my latest setup. Verdict: Good and Bad Good - with the driver bang in what would be the middle position in my guitar, no squeal - not even a hint. Bad - Harmonic mode squeals like a Pig having an orgasm Bad - In normal mode the fizz is back Good - the fizz in middle position is not much worse than it was in neck position with my old circuit. Question: With a stacked humbucker (or a normal one with inside coil attenuated), would the fizz be reduced even more - perhaps enough to make middle position a realistic option ? VERY GOOD After this experiment, I got paranoid that my initial statement that my new circuit has dramatically reduced the fizz may have been wishful thinking, and that what I had believed to be clipping from my amp sim was actually fizz from the sustainer. So I dragged my old Pignose out of the pile of Junk it was festering in and plugged the guitar straight into it.... clean tone, no clipping, no distortion, mucho sustaining, NO FIZZ !! probably if you plugged into an ultra clean amp with very good headphones or monitors, you would notice some quiet fizz or at least woolyness, but through a normal guitar quality amp, it seems clean to me Col Link to comment Share on other sites More sharing options...
fookgub Posted November 19, 2006 Report Share Posted November 19, 2006 Well, I built Col's circuit today. I had to add some capacitance to the supply rails to get it to quit oscillating. Now it works fine on the bench with a function generator. When I hook it up to my guitar, it starts to oscillate. This is no surprise really... the Ruby-Fetzer oscillated, too, and at the same frequency (~4kHz). I think this is attributable to either capacitive pickup in the guitar wiring or direct feedback from the driver to the pickup. Has anyone run into this before? How did you combat it? Link to comment Share on other sites More sharing options...
spazzyone Posted November 19, 2006 Report Share Posted November 19, 2006 after the last couple of post's im wondering? Col.. is your setup in a strat?. i know Pete's is but im not sure of yours when i switched my rail to the middle position in my strat the responce droped and when i think about it i also had a little fizz but in my B.C Rich which is rear routed/top loadedt this did not happen it is fully copper sheilded but so is my strat. could the cavity be a problem (pots/switches?) it makes me wonder still...if all are overlooking the obvious? is less more? the outbord im using ( that is all but functional minus harmonic/fundimental mode which i cant switch (or at least have no control over) has "zero noise" but i just don't understand why outboard control is so over looked. in the sense all guitars could have a sustainer without the problem of space limitations or power problems as you only have 1 controler and many drivers and the power of freedom? Pete i belive will hold the answer as he has the same rail i do. which with no mods works great minus the harmonic/fudemental mode problem. but im sure he will rewind it into a proper driver i still think anything made into a small circut can be made better in a pedal of some kind with less limitations this comment is meant for all readers. think about this there.are already guitars with sustainers but how many sustainer system's?????????? why not let it be universal system. like a line6 pod one pedal works with every guitar? and CurtisA's soundclip is such great use of the sustainer....kudos Link to comment Share on other sites More sharing options...
curtisa Posted November 19, 2006 Report Share Posted November 19, 2006 Well, I built Col's circuit today. I had to add some capacitance to the supply rails to get it to quit oscillating. Now it works fine on the bench with a function generator. When I hook it up to my guitar, it starts to oscillate. This is no surprise really... the Ruby-Fetzer oscillated, too, and at the same frequency (~4kHz). I think this is attributable to either capacitive pickup in the guitar wiring or direct feedback from the driver to the pickup. Has anyone run into this before? How did you combat it? Are you using the stacked single coil driver/pickup that Pete and myself used? I had high pitched oscillation from mine too. Don't know what frequency exactly, but it would've been around the 4k area. I think Pete found that he had to disconnect ALL the pickup wires except the source pickup to get his to settle down. I found I had to short the pickup wires together on my driver/pickup stack to get rid of the squeal. but i just don't understand why outboard control is so over looked. in the sense all guitars could have a sustainer without the problem of space limitations or power problems as you only have 1 controler and many drivers and the power of freedom? I'm personally not particularly interested in extra outboard doodads just to get the sustainer working. I'd much rather have a system where I just plug the guitar into an amp (or permanent rack) using a plain old guitar lead. The outboard control option also becomes a problem if you want to use the guitar in a live situation with a wireless. That said, I can see that many other people might want to have an outboard controlled sustainer as it opens up a lot more tonal trickery with the effect. Just not my cup 'o tea I guess and CurtisA's soundclip is such great use of the sustainer....kudos Hehe, thanks Spazzy Interesting side note - I tried out the sustainer guitar this afternoon while playing with a slide. Sounds quite bizarre, almost Theremin-like. Harmonic mode works on the slide too. Cheers, Curtis. Link to comment Share on other sites More sharing options...
psw Posted November 19, 2006 Author Report Share Posted November 19, 2006 With a stacked humbucker (or a normal one with inside coil attenuated), would the fizz be reduced even more - perhaps enough to make middle position a realistic option ? The sustainer strat of mine does have a cheap stacked humbucker in the bridge position. clean tone, no clipping, no distortion, mucho sustaining, NO FIZZ That's a fantasic result, col... Well, I built Col's circuit today. That's good too...independant verification. The oscillation is likely to be to do with the driver if it had this effect with the fetzer/ruby too. I would suspect some kind of loose windings perhaps. Pete i belive will hold the answer as he has the same rail i do. which with no mods works great minus the harmonic/fudemental mode problem. Well there will still be some time before I can do this experiment. I have a extension speaker jak in my main amp that could perhaps replicate your experiments...but perhpas the secret is in your magic PA amp...who knows...we'll have to see! Good - with the driver bang in what would be the middle position in my guitar, no squeal - not even a hint. Bad - Harmonic mode squeals like a Pig having an orgasm Bad - In normal mode the fizz is back Good - the fizz in middle position is not much worse than it was in neck position with my old circuit. This is a good result...I take it that the driver was above the strings, so the effect would be better if it were properly mounted. If the device could be made smaller with Tim's coils or something...could be on to something. Certainly it is an endorsement of the rail design. I did get some similar problems with the harmonic mode with the Hex stuff. I think that there is something to do with the ground wiring common to both the pickup, the driver and the driving circuit... Also, I believe that the high frequencies propagate further through EMI than lower frequencies so that the distortion is more of a fizz and worse in harmonic mode, than a "buzz" for instance. Perhaps a bi-lateral design my work even better, enough to tip the balace a little further... The mid-driver idea does offer some advantages...simpler wiring and more tonal variation with pickup selection, perhaps an improved "action" response... But, there may well be a few drawbacks so even if I do get it to work, it may not be the prefered placement of the device anyway... As dizzy demonstrated, the mid driver is possible...but is it the prefered option...time will tell Thats assuming it works AT ALL - but IF it does, it may be another step towards realising a middle position driver (with bridge and neck humbuckers). Well...all we can do is test ideas and assumptions. There is certainly a possibility of some improvement. I was not thinking aboput the fizz aspects so much with the single coil of a humbucker source, so much. More, I was thinking that it would be a lower impedance, cleaner source that is sampling the string from a much narrower window. I take it that all of these posts of mine are stream of consciousness stuff...obviously there is no editing ...so, sometimes the ideas flow out as I am writing and the original intent is submerged by other things that come to mind as I type. So...it may or may not work or be of benefit...however, it is certainly worth a go, even if it would be a small improvement, these things will progress in little steps....this may be one of those steps. One reason I thought of it was that col's HB and a lot of other's like it are pretty hot and sensitive...a split could yield a less sensitive and less hot (read, distorted) source. It may also prove to be a better match for the input of the circuit impedance wise... On the otherhand, it may prove to be of no benefit at all... I would miss the mid pickup too...making an effective mid driver and retaining a reasonable single coil sound would be tricky. On the way to work today I was thinking of some pickup designs. It could be possible to make a bi-lateral single coil pickup...and driver with some of the components of a standard single coil design. I saw a pick of a tele pickup made in this way and tonally it would be an improvement over the stacked coils that are typically out there. Typically rails are hot and designed to emulate a humbucker in a single coil size...this is the type of thing spazzy's pickup is...not really a mid pickup design. Perhaps I might rewind it with thicker wire and less output for the job. If I did this, you could block up the bobbins, wind the driver in epoxy...unblock them and wind the pickup coils below them...the result would be something that looks exactly like a rail pickup but have the driver hidden in the original bobbins. It would be well made and solid and more compact than col's present rail driver and may again tip the balance for the mid driver and the full rail idea. Of course this too would not sound like a conventional single coil...but it could be interesting...maybe a bit of a growl like a p-90 mignt come out...that would be cool to put into the mix... All of these ideas are moving away from a typical DIY device into pickup construction and would not be something for most to do unless they are already into making their own pickups. Still, it does present some interesting possibilities for a new venture in that direction... I could see a pickup making thread that would rival the AMPAGE forum for inventiveness and ideas. I know there are people winding pickups here so there would be interest. Other forums are pretty conservative and are seeking "vintage" sounds and constructions. Certainly the results are more predictable...but for having fun, if you are going to go to all the trouble and expense of winding pickups, you may as well shoot for something different... Anyway...better run....good work all...I will miss you when I am off the net in a week or so...remember, now is the time because I could be gone a little while!!! pete Link to comment Share on other sites More sharing options...
col Posted November 19, 2006 Report Share Posted November 19, 2006 Well, I built Col's circuit today. I had to add some capacitance to the supply rails to get it to quit oscillating. Now it works fine on the bench with a function generator. When I hook it up to my guitar, it starts to oscillate. This is no surprise really... the Ruby-Fetzer oscillated, too, and at the same frequency (~4kHz). I think this is attributable to either capacitive pickup in the guitar wiring or direct feedback from the driver to the pickup. Has anyone run into this before? How did you combat it? Good point, I also have a power supply cap thats not on the schem accross the battery. Try wiring up only the bridge pickup and the driver - disconnect everything else. after the last couple of post's im wondering? Col.. is your setup in a strat?. i know Pete's is but im not sure of yours when i switched my rail to the middle position in my strat the responce droped and when i think about it i also had a little fizz but in my B.C Rich which is rear routed/top loadedt this did not happen it is fully copper sheilded but so is my strat. could the cavity be a problem (pots/switches?) My guitar is a Riverhead Jupiter700 !! its a bolt on neck 25 1/2 scale with trem and two humbuckers. I removed the neck humbucker for sustainer development. The bridge pickup is a Duncan Jeff Beck - a very 'hot' pickup - the original Seymour Duncan IIRC. I'm personally not particularly interested in extra outboard doodads just to get the sustainer working. I'd much rather have a system where I just plug the guitar into an amp (or permanent rack) using a plain old guitar lead. The outboard control option also becomes a problem if you want to use the guitar in a live situation with a wireless. My sentiments exactly With a stacked humbucker (or a normal one with inside coil attenuated), would the fizz be reduced even more - perhaps enough to make middle position a realistic option ? The sustainer strat of mine does have a cheap stacked humbucker in the bridge position. The truth comes out at last just kidding - I think you've mentioned it before, but until now, I didn't really think about it in this way - maybe your stacked bridge pickup is why your results with the basic system have been so much better than everyone elses ! e.g. no major fizz problems in normal mode Good - with the driver bang in what would be the middle position in my guitar, no squeal - not even a hint. Bad - Harmonic mode squeals like a Pig having an orgasm Bad - In normal mode the fizz is back Good - the fizz in middle position is not much worse than it was in neck position with my old circuit. This is a good result...I take it that the driver was above the strings, so the effect would be better if it were properly mounted. If the device could be made smaller with Tim's coils or something...could be on to something. No, it was under the strings, I just managed to squeeze it in there - couldn't play high on the neck, but there was just enough room for testing. Certainly it is an endorsement of the rail design. I did get some similar problems with the harmonic mode with the Hex stuff. I think that there is something to do with the ground wiring common to both the pickup, the driver and the driving circuit... Also, I believe that the high frequencies propagate further through EMI than lower frequencies so that the distortion is more of a fizz and worse in harmonic mode, than a "buzz" for instance. The rail driver is definately an improvement over the single coil You're probably right about the high frequency thing... oops, gotta run Col Link to comment Share on other sites More sharing options...
psw Posted November 19, 2006 Author Report Share Posted November 19, 2006 The sustainer strat of mine does have a cheap stacked humbucker in the bridge position. The truth comes out at last just kidding - I think you've mentioned it before, but until now, I didn't really think about it in this way - maybe your stacked bridge pickup is why your results with the basic system have been so much better than everyone elses ! e.g. no major fizz problems in normal mode Well...I am not too sure about this. Just to be clear, the driver is built on a very ordinary single coil pickup in the neck, the mid is identical without a driver and the bridge a stacked pickup...(cost about A$30 new....) This guitar was sacrificed to all kinds of experiments. One idea I had was that if it would work on such a cheap POS single coil guitar, it would work on anything...a lot of testing was done with this and another guitar when it had single coil pickups only in it... I don't know that anyone has really replicated what I have done, everyone's has been a little different. A few people have tried it and I think most have got some kind of result, many early on did not take it through to installation though. I think Curtis has gotten a similar result to me for instance, Primal's HB conversion worked...and col, you have a completely different driver/pickup combo but did try the basic version and it did 'work', did it not? The ones that weren't too successful really did comprimise the receipe that I laid down. Galaga Mike, who did the first tutorial used a different wire guage and neo mags (from disk drives)...it did work but couldn't get the high strings going... I did get noticable fizz from the driver leads and in the end solved this by routing the driver leads through the trem cavity, away from the pickup wires and controls. I also did some major surgery and gave the circuit it's own cavity away from the pickup controls (although directly behind the output jack)...this could have more of an influence... Also, my circuit is different again from others... I think a lot of the reason for the success of my guitar is simply that I had done so much work by the time I got around to making it, that it really was built well ...I had made a lot more difficult designs, the circuit had been tested and used for a long while and built several times, the driver was a direct copy of a previous one (so I had had a practice run)...and, I did have to do a fair amount of work on the installation to make the thing go...bypassing problems for instance were unanticipated... But this was pioneering stuff...now that it is done, we know what to avoid, we have a receipe to follow...I didn't have that...I just plugged away at it till it did work! Similarly, I think a mid driver will work, if I plug away at that too! Not everything works for trying of course (like my marriage apparently ), no use flogging a dead horse, but you do have to try... I do know that the fizz will go completely with use of the tone control...but then you get no high string response or treble...hahaha. I even had a tone control into the front end of the circuit to trim this back but after some fiddling around, with the installation it was removed... Most if not all have been successful in recent times...some may need to redo the driver to get even better results...but I do think we have the basic driver down now and I think all should be able to acheive the performance of my guitar if they really want to... pete Link to comment Share on other sites More sharing options...
col Posted November 19, 2006 Report Share Posted November 19, 2006 Well, I built Col's circuit today.... btw, did you breadboard it, or build it on strip or perf board? If its breadboarded, wait a while until you make a more permanent version, I have a much more effective 'mixed mode' approach now. The switchable input cap thing doesn't make a good mixed mode, it helps a little to encourage harmonic bloom, and at the same time reduced low end performance (as you would expect), but its not enough of a difference from fundamental mode to be worth wasting a switch on... What I'm doing now is based around an all-pass filter. This provides a phase shift that ranges form nearly 180º at 82 hz (low E) to almost 0º (360 really) at high e 12th fret.... in practical use, most notes up to about the 8th or 9th fret bloom quickly and easily to (mostly) octave harmonics.... higher up the fretboard, its back to fundamental mode. There is still reduced performance on the low E string, but I can live with that. Implementation wise, the idea is to share the op-amp used for full harmonic mode.... this means using a 2P3T toggle switch, a rotary switch, a combination of switches, or compromising and choosing one or the other of the two harmonic modes. Once I have this fully tested, I will post a scheme and then when its built and verified, the strip-board layout. Col Link to comment Share on other sites More sharing options...
col Posted November 19, 2006 Report Share Posted November 19, 2006 (edited) The sustainer strat of mine does have a cheap stacked humbucker in the bridge position. The truth comes out at last just kidding - I think you've mentioned it before, but until now, I didn't really think about it in this way - maybe your stacked bridge pickup is why your results with the basic system have been so much better than everyone elses ! e.g. no major fizz problems in normal mode Well...I am not too sure about this. Just to be clear, the driver is built on a very ordinary single coil pickup in the neck, the mid is identical without a driver and the bridge a stacked pickup...(cost about A$30 new....) This guitar was sacrificed to all kinds of experiments. One idea I had was that if it would work on such a cheap POS single coil guitar, it would work on anything...a lot of testing was done with this and another guitar when it had single coil pickups only in it... I know, what I'm talking about is that the pickup you are using to feed the sustainer is a stacked humbucker - this may be significant (in fact a cheap one may be better than a kinman with its asymetrical coil setup) I think Curtis has gotten a similar result to me for instance, Primal's HB conversion worked...and col, you have a completely different driver/pickup combo but did try the basic version and it did 'work', did it not? I and I believe Curtis (?) and Tim have had issues with fairly obvious fizz... the fizz I've had will not go away with the tone control ! I was surprised when you said that it was less of a problem on your setup and that it was only really noticable in harmonic mode, but being reminded that you use a stacked humbucking pickup rather than a normal single coil suggested to me that this may be a partial explanation. I did get noticable fizz from the driver leads and in the end solved this by routing the driver leads through the trem cavity, away from the pickup wires and controls. I also did some major surgery and gave the circuit it's own cavity away from the pickup controls (although directly behind the output jack)...this could have more of an influence... Also, my circuit is different again from others... Did you change from using a normal single coil pickup to using a stacked humbucker at some point? if so, did you notice (for whatever reason) a reduction in fizz at around the same time? As far as leads, have you tried making one of those inter-8 weave cables I posted about - its really not difficult to do, and they seem to work - I'm using a driver cable nearly a meter long that goes from an open breadboard (nest of wires) into the back of my guitar right past the pickup and its cables.... seems to be very little EMI from it. ..... I'll try to explain my idea about why a stacked humbucker could be better than a traditional side-by-side one using some simplified (and quite possible wrong) maths: my understanding (is this correct?) is that the energy of the magnetic radiation falls off as the inverse-square of distance... so lets say that the energy at the driver is 1000 units - doesn't matter what they are, distance from driver to inside coil = 9.5 cm distance from driver to outside coil = 10.5 cm the energy at the inside pickup coil will be 1000x(1 / (9.5x9.5)) = 11.08 units while at the outside coil it will be 9.07 units That is quite a big dicrepency - after the humbucking cancellation has taken place roughly a fifth of the magnetic radiation from the driver will still be in there.... if the coils are stacked instead of side by side, they have the same distance from the driver, therefor the cancellation will be much more efficient If we look at a mid position driver from the same POV: distance to inside coil is 4.5 distance to outer coil is 5.5 again assuming the same imaginary 1000 units from the driver, energy at the inside coil of a standard humbucker is 49.4 energy at outside coil is 33.06 So this time it even worse !! there's roughly 4 times as much radiation and in a horrific double whammy situation, _two_ fifths of the EMI from the driver will fail to be cancelled by a normal humbucker ! This may be a bunch of nonsense - needs verification by someone with more knowledge than me in this area, but it matches my experimental discoveries in terms of moving the driver closer to the pickup, and as I said, may help to explain why you had less trouble with fizz even using a similar specced driver and a functionally similar circuit... noting also that you have a heavily clipped driver signal and that that would create a huge fizz issue on my setup and on that of at least one other sustainiac here (can't remember his name) cheers Col Edited November 19, 2006 by col Link to comment Share on other sites More sharing options...
fookgub Posted November 19, 2006 Report Share Posted November 19, 2006 btw, did you breadboard it, or build it on strip or perf board? If its breadboarded, wait a while until you make a more permanent version, I have a much more effective 'mixed mode' approach now. It's breadboarded. I actually didn't include the switchable cap on the input. I'll try out your new harmonic mode when it's ready, but I'm not committing anything to solder until I can fully evaluate the performance. That means getting these oscillation problems out of the way. This is something that has plagued my sustainer efforts from the very start. I have tried disconnecting everything but the bridge pickup and driver before (back in the Ruby Fetzer days), and the entire guitar is wired with shielded cable. I think the next step is to try a different bridge humbucker. The one in my guitar is a stock Ibanez bridge pickup. It could be more susceptible to oscillation because it's unpotted and slightly overwound. I have a Gibson style covered pickup that reads only 5.5k that I'm going to try next. Hopefully the cover and fewer windings will help out. Link to comment Share on other sites More sharing options...
bancika Posted November 19, 2006 Report Share Posted November 19, 2006 (edited) Hello, I finally made a few clips of my sustainer during hand test. I recorded from guitar to preamp and then to PC sound card. B string mode 1 B string mode 2 D string mode 1 D string mode 2 I'm really not so sure which mode is which any more. The one I expected to sustain more actually gives me harmonics and "clean" one sustains much less with same settings. IIRC settings are Gain 0%, volume 60%. Also, problem with G string remains the same. No matter which string I hit G has most chance of vibrating (followed by low E). Also, harmonic mode (which sustains more) increases vibration all time, some kind of AGC would surely help there. If I reduce ruby volume that effect decreases but then other mode is even more subtle. By the way, here's a photo of my Fetzer/Ruby that drives sustainer. Link I'll make bobbin for that piece of magnet I have and try dual coil blade design to try both. One more thing, I've found another magner rod but it's broken, so it's only 52mm long. I checked with my guitar and at 24th fret it's only about 1-2mm wider than string spacing. Does it make any difference if I use that one instead of 60mm long one? Cheers, Bancika Edited November 19, 2006 by bancika Link to comment Share on other sites More sharing options...
fookgub Posted November 20, 2006 Report Share Posted November 20, 2006 I think the next step is to try a different bridge humbucker. Tried it, no dice. Even with only the bridge pickup and driver in the circuit, it oscillates with every pickup I have. I wound a new driver tonight, so I'll try that out tomorrow. Link to comment Share on other sites More sharing options...
col Posted November 20, 2006 Report Share Posted November 20, 2006 (edited) I think the next step is to try a different bridge humbucker. Tried it, no dice. Even with only the bridge pickup and driver in the circuit, it oscillates with every pickup I have. I wound a new driver tonight, so I'll try that out tomorrow. Is your driver single coil, or dual rail ? I've been using a dual rail for all recent tests as it produces far fewer EMI problems (including being much less sensitive to sqealing feedback) Col Edited November 20, 2006 by col Link to comment Share on other sites More sharing options...
col Posted November 20, 2006 Report Share Posted November 20, 2006 Hello, I finally made a few clips of my sustainer during hand test. I recorded from guitar to preamp and then to PC sound card. B string mode 1 B string mode 2 D string mode 1 D string mode 2 I'm really not so sure which mode is which any more. The one I expected to sustain more actually gives me harmonics and "clean" one sustains much less with same settings. IIRC settings are Gain 0%, volume 60%. Also, problem with G string remains the same. Sounds like your mode 1 is harmoinic mode. Also sounds like the frequency response rolls off at too high a frequency - that would explain why the harmonic mode is loud while the fundamental is almost not there... What happens when you increase the gain ? It might be that to get fundamental going, you need a gain setting that pushes the harmonic mode into oscillation... Did you super double, tripple check your circuit for dry/unsoldered joins, wiring errors, caps the way round, layout design errors etc. ? You may need to change output cap (and possibly input) to larger values... Another possible cause is the driver - are you using the suggested wire guage ? What about core material and dimentions? What is the resistance reading for the coil? No matter which string I hit G has most chance of vibrating (followed by low E). Also, harmonic mode (which sustains more) increases vibration all time, some kind of AGC would surely help there. If I reduce ruby volume that effect decreases but then other mode is even more subtle. G is the most 'lively' string on my setup as well - you have to damp it if you want others to ring... AGC helps in many ways, but it doesn't stop the G string overwhelming the others when you don't use damping techniques. things that can help are - adjust the pole pieces of your pickup, use different string guages, build a driver core with a staggered core (vary height, thickness or both), fit a partial shield plate to limit the magnetic pull on the G string - one of the plethora of patent pictures Pete posted (don't try to say that while drunk) shows this idea. Col Link to comment Share on other sites More sharing options...
psw Posted November 20, 2006 Author Report Share Posted November 20, 2006 I am a little baffled by some of this I have to admit.... Some strings will tend to vibrate more than others, usually it is the lower strings, however... The coil will have it's own resonant frequency and the placement of the driver along the string will influence phase relations for different pitches. A G note though always makes me suspicious of power interferance issues if there is any power supply in the chain. Also, resonant oscillations in the circuit could be producing a "note" a little... The coil itself could produce a note via internal vibrations if the potting is not sufficient or there are loose windings...Branislav's does not look like there would be too much of a problem there from the photos. The sound clips show that the string is sustaining...a little of the fizz there too...hmmm It does not sound like an overly powerful sustain...kind of like mine when it is turned down, the battery is going flat, or the pickups are loaded by the volume or tone control on the guitar. My driver is built flat...the distance is more from the g and d strings than it is from the other strings...perhaps this is why I don't have such a bad effect...if so, it wasn't by design... A broken magnet is ok generally...you could use multiple magnets even...if under a blade it will still magnetise the strings more or less evenly I suspect... As far as my stacked HB is concerned I really am not sure if I had installed the stack at the same time as the sustainer or not. I know I tested the device without it. I did use the stack to give the device it's best shot...the "companies" both specify HB pickups to be used with their system I believe... I may even have made the pickup/driver out of the old bridge pickup... Could there be some confusion as to the difference between the dual coil driver (to limit/cancel EMI) and the dual coil pickups (to limit/cancel RFI). Pickups... The coil of a pickup can act like an antenna picking up stray radio signals and interferance and amplifying them. A dual coil design pickup up these signals but because of their reverse winding and reverse polarity, cancel out these RF signals. They still will pick up the magnetic interferance of the strings vibrating in their fields (the RWRP arrangement of magnetics and coils allows for the signals in the coils to be cancelled but the sensed magnetic signals from the strings to be added together). A conventional HB derives some of it's sound from the wider area of string that it is sampling and that because the coils are not in the same place, some signals are cancelled along with RF frequencies. A stacked coil, will sound more single coil like as the sampled area is the same, but the distance of the coils from the strings are different...sometimes they can (like mine) sound a little tinny. A rail pickup has a slightly wider than single coil sampling area but similar qualities to the HB. Dual coil pickups in a single coil size however, as with very hot HB's often suffer from the use of very fine winding wire. This serverly effects the frequency response of the pickups often making them muddy and less detailed than lower impedance models. The dual coil, humbucking designs are rejecting RFI but remain sensitive to magnetic variations, such as the strings vibrating through their magnetic field. Drivers... Ok...so a driver puts out electromagnetic energy via it's coil to act upon the magnetic field of it's magnet and the strings that vibrate through this field. By vibrating the magnetic field with the strings in them, the strings too are vibrated. The dual coil driver designs seek to cancel out EMI so that the area of electromagnetic radiation is kept contained and not leak into the pickup that will sense these variations just as it senses the variations of a metal string vibrating in it's field. Have a think about these two systems and their interaction... I have got to run now...some more of life's disasters are awaiting me I am afraid, some bad news has come my way... pete Link to comment Share on other sites More sharing options...
bancika Posted November 20, 2006 Report Share Posted November 20, 2006 Here's more info: as seen on photo, driver is wounded on old strat pickup bobbin with core about 60x6mm with magnetized rods as pole pieces (I assume they are AlNiCo V). Before I connected amp to driver I tested it with speaker to make sure everything is working OK. Wire is 0.20mm Pete sent me, which is the same as he used, so I ruled that out. I measured about 8.2ohm of DC resistance of coil, which should be fine. I'm still trying it with power supply, so it might be the reason. As for 2nd shot, do you suggest trying to wind around blade and put magnet under or just wind directly to magnet. I have magnets suitable for both designs, one has 5x6mm profile and one is about 5x12mm. I hope everything's OK Pete! Best regards Link to comment Share on other sites More sharing options...
psw Posted November 20, 2006 Author Report Share Posted November 20, 2006 I'm still trying it with power supply, so it might be the reason. I would definitely loose the power supply, try it with a battery!!! You could even have troubles from other power supplies in the chain, preamp or even computer... As for 2nd shot, do you suggest trying to wind around blade and put magnet under or just wind directly to magnet. I have magnets suitable for both designs, one has 5x6mm profile and one is about 5x12mm. Is this another single coil driver or some other design. One problem with winding on the magnet is that you are stuck with those dimensions for the core. Another, is that you will have to destroy the device to recycle the magnet. With a blade design the magnet can be used as often as you like for other ideas and you can vary the core material and size. There are advantages to an internal magnetic core though...possibly faster, different field characteristics...but, the main thing is you can make it more compact... The thin driver design of mine is intended to limit EMI by this compactness and to maximise overlapping windings to make a powerful yet contained electromagnetic device. It was conceived through experimentation and intuition. There are many approaches however, sheilding and coil orientation are two others, as well as dual coil EMI reducing technology. I am surprised from the clips that the sustaining effect isn't a little more powerful. You should be able to run the thing full blast (as I do in my set up with lots of preamp and 200x amp) without squealing in both modes, provided there is enough distance (ie held over the neck) from the pickup. I hope everything's OK Pete! It is a long hard road...and it seems to be getting rockier.... pete Link to comment Share on other sites More sharing options...
fookgub Posted November 21, 2006 Report Share Posted November 21, 2006 Is your driver single coil, or dual rail ? I've been using a dual rail for all recent tests as it produces far fewer EMI problems (including being much less sensitive to sqealing feedback) Col I've been using single coils. I've been away from the sustainer world for a while, so I didn't know there are dual coils floating around now. I looked around the thread this morning, but I couldn't really find anything... got a link to some construcation notes? Also, I tried the driver I made last night. It's potted in CA and completely solid, but it still feeds back. Actually, I'm curious about how anyone got the single coil driver to work, since it has never worked with my setup, even through several iterations of drivers and amps. I wonder if there is something wrong with my setup that I've overlooked. Link to comment Share on other sites More sharing options...
psw Posted November 21, 2006 Author Report Share Posted November 21, 2006 Have you seen my pictorial on building my single coil pickup driver? pictorial This is the actual pickup in my guitar that is heard in the clips and is a very basic single coil, 3mmm driver. By CA, I gather that is some kind of super glue. This is not recomended and may be a part of the problem. Super glue may be strong, but it does not have gap filling properties. The solvent may even strip the enamel on the wire causing shorts. It may shrink back also exposing air gaps and striping the wires protective coating which is very thin. As the wire will heat and expand in operation, this may take it's toll on the glue, strip the winding and lossen the winds to create problems as you are experiencing... I used PVA or white wood working glue. It may not dry quite solid but is safer to use, fills some gaps, will not harm you or the coil and gives you a lot of working time to get it quite right. Also, it is slightly rubbery so will take expansion and at least dampen any vibration, especially high frequencies that are the main problems. CurtisA and Bancika have built drivers based on this design recently... If the amp is working all right through a speaker you should be ok there...so the driver is what is most likely where you need to look. Could you post some pics or something... You are testing the driver above the strings and over the neck well away from the pickups, yes? A full installation should only be attempted after verification that everything else is working as it should. There are all sorts of variables to consider so they have to be eliminated one at a time... The dual coil systems have been talked about, but I think col's is the only one actually built and does work. He has also made a single coil that works but feels that the rail design is uperior, which it may well be. However, the single coil does work, furthermore, it works in my cheapo strat with multiple pickups and quite satisfactorily too, so be in no doubt that the project can work...it is just a little trickier than it may at first appear and draws on some skills that are not usual and may take some practice (principly arts and crafts, trouble shooting and perserverance)... As many details as is possible can always lead to more advice, but you will need to keep trying...for now testing outside of the guitar to get the thing working is the order of the day... pete Link to comment Share on other sites More sharing options...
bancika Posted November 21, 2006 Report Share Posted November 21, 2006 Is this another single coil driver or some other design. One problem with winding on the magnet is that you are stuck with those dimensions for the core. Another, is that you will have to destroy the device to recycle the magnet. With a blade design the magnet can be used as often as you like for other ideas and you can vary the core material and size. There are advantages to an internal magnetic core though...possibly faster, different field characteristics...but, the main thing is you can make it more compact... I'm thinking about stacked coil design. I'll try to find some blade material and try to do it with separate blade magnet, then. It sounds more flexible. It is a long hard road...and it seems to be getting rockier.... pete Sorry to hear that, hope everything will be ok Link to comment Share on other sites More sharing options...
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