Sabudum Posted February 23, 2012 Report Share Posted February 23, 2012 Hello, im new to this forum, and i've been accompanying the Sustainer Thread for quite a while, and now that i decided to finally build it, it just won't work for me, and i can't seem to find the problem, after a thorough search through this forum i couldn't find the problem, i even tried rebuilding everything, from circuit to driver, but nothing seems to fix it, i tested everything individually, and everything works fine, the circuit works, it amplifies the signal, the driver works, and if i wire it as a pickup it will even get some signal from the strings. I used the Ruby amp project as the circuit, and built the driver from an old single coil, dual blade pickup, my guitar has only one hum-bucker. Can someone help me pinpoint what's wrong with my build? Quote Link to comment Share on other sites More sharing options...
DarkAvenger Posted February 24, 2012 Report Share Posted February 24, 2012 I'll assume your following psw's tut. If you get zero sustain, something is very wrong. The lower three strings will almost always react even under less than ideal circumstances. As always, photos are best for diagnosis, but I can try to help. Have you tried replacing the driver with a speaker? This is a pretty important step, you should be getting a crisp clear sound, no clipping. Ok, some basics, what gauge wire did you use, coil thickness, is there a buffer before the amp(usually just a JFET transistor), did you build the circuit or buy one, did you swap the normal 220uf cap at the out for the recommended 100uf. Quote Link to comment Share on other sites More sharing options...
dpm99 Posted February 24, 2012 Report Share Posted February 24, 2012 Quote Link to comment Share on other sites More sharing options...
psw Posted February 24, 2012 Report Share Posted February 24, 2012 I support the project via email due to constant trolling...if serious about it, feel free to email and will see what I can do to help. Pictures and such helps a lot, but many many have built the things successfully...while some have failed to do some important steps as DA points out. If you have a circuit and it is working with a speaker and made the coil to spec and tested that...some sustain as is pointed out really is a given so something is clearly wrong but there is not enough information here to clarify anything as it is a little vague to say the least. Most people have succeeded in this project if they have the skills, yes even with the ruby circuit or a range of other options that fit the bill. As I say, due to trolling, the project is not supported at PG or publicly now...as you can see, some animosity all round still, so I will not be playing any part in it. My email is on my members page and I can provide some more concise documentation that might help. If you insist on a public display of this topic...well then, perhaps some pictures are in order and certainly more details...best of luck... Quote Link to comment Share on other sites More sharing options...
col Posted February 24, 2012 Report Share Posted February 24, 2012 Hello, im new to this forum, and i've been accompanying the Sustainer Thread for quite a while, and now that i decided to finally build it, it just won't work for me, and i can't seem to find the problem, after a thorough search through this forum i couldn't find the problem, i even tried rebuilding everything, from circuit to driver, but nothing seems to fix it, i tested everything individually, and everything works fine, the circuit works, it amplifies the signal, the driver works, and if i wire it as a pickup it will even get some signal from the strings. I used the Ruby amp project as the circuit, and built the driver from an old single coil, dual blade pickup, my guitar has only one hum-bucker. Can someone help me pinpoint what's wrong with my build? You say you used a single coil dual blade pickup - this doesn't make sense. Do you mean a single coil 'sized' humbucker that actually has two coils? or a single coil pickup that has a strange dual bladed core? If it's a single coil driver, then winding to Pete's specs should have given you some definite sustain action - even if not ideal. There should be something to work with. If it was a 'rails' humbucker style with two coils, then it is very important how you connect the coils. Assuming the pickup used the standard humbucker approach of a single bar magnet, at the bottom between the two rails, then the coils need to be wired out of phase with each other, so that they push and pull at the same time. If you wire them in phase, one will push while the other pulls == no sustain ! Whether you wire them in series or parallel is also important - if you would each coil to 4 ohm nominal impedence, you should wire them in series, if you would them to 16ohm each, then wire them in parallel (If you would them to 8 ohms, then oops!... I recommend wiring them in parallel and wiring a 4 ohm half watt resistor in front of them to bring the overall impedance up to around 8ohm). As has been suggested by everyone else, you need to post some photos and details of the specs of your driver. The wire gauge you used for the coil(s), number of turns, DC resistance of coils, how they are wired, the more detail the better. good luck Col Quote Link to comment Share on other sites More sharing options...
Sabudum Posted February 25, 2012 Author Report Share Posted February 25, 2012 (edited) WOW! Thanks for your help guys, about the pickup i used to make the driver, ir actually contained 2 coils, with 2 cores, obviously, like this one: LINK And i made my driver with 0.2 gauge wire, the bobin thickness is precisely 3 mm, everything checks out, i tried also replacing the driver with a speaker, the sound is clean, perfect, although, i never added a buffer before the pre-amp, maybe that is the problem? Also, i build everything myself, including the circuit. Another thing, although the pickup i used contained 2 coils, i made the driver with only one coil, altering this way, the entire structure of the original pickup, where it had 2 coils, i made only one occupying the same space, this way the problem about the phase with the coils would be nonexistent. I also left the coil with only one core, otherwise it would generate other problems that would give me a headache. hehe And at last, an image of my driver, please understand i couldn't take the best picture of it, as my camera is very cheap: I'll keep moving forward, thanks! Edited February 25, 2012 by Sabudum Quote Link to comment Share on other sites More sharing options...
col Posted February 25, 2012 Report Share Posted February 25, 2012 WOW! Thanks for your help guys, about the pickup i used to make the driver, ir actually contained 2 coils, with 2 cores, obviously, like this one: LINK And i made my driver with 0.2 gauge wire, the bobin thickness is precisely 3 mm, everything checks out, i tried also replacing the driver with a speaker, the sound is clean, perfect, although, i never added a buffer before the pre-amp, maybe that is the problem? Also, i build everything myself, including the circuit. Another thing, although the pickup i used contained 2 coils, i made the driver with only one coil, altering this way, the entire structure of the original pickup, where it had 2 coils, i made only one occupying the same space, this way the problem about the phase with the coils would be nonexistent. I also left the coil with only one core, otherwise it would generate other problems that would give me a headache. hehe how many turns on the coil? what is the dc resistance of the coil? how is the magnet attached to the core? Quote Link to comment Share on other sites More sharing options...
Sabudum Posted February 25, 2012 Author Report Share Posted February 25, 2012 how many turns on the coil? what is the dc resistance of the coil? how is the magnet attached to the core? there's 113 turns to the coil, in order to have 8 ohms impedance The resistance is 1.378 ohms and resistance per meter is 0.549 ohms/meter the magnet is simply attracted to the core, as the core is a steel core, so the magnet naturally attaches itself to it, i left the original magnet that came with the pickup, as i couldn't find any other, that was better. Quote Link to comment Share on other sites More sharing options...
col Posted February 25, 2012 Report Share Posted February 25, 2012 how many turns on the coil? what is the dc resistance of the coil? how is the magnet attached to the core? there's 113 turns to the coil, in order to have 8 ohms impedance The resistance is 1.378 ohms and resistance per meter is 0.549 ohms/meter Which resistance is 1.378 ohms? the magnet is simply attracted to the core, as the core is a steel core, so the magnet naturally attaches itself to it, i left the original magnet that came with the pickup, as i couldn't find any other, that was better. that should be fine. I'm concerned about the resistance. with Pete's design of drive coil, the impedance at low frequencies is dominated by DC resistance, so DC resistance needs to be about 8ohms. if its a lot lower, it could cause the LM386 to fry, or go into shutdown protection (if it has that?). Where is the 1.378 ohms figure from? cheers Col Quote Link to comment Share on other sites More sharing options...
Sabudum Posted February 25, 2012 Author Report Share Posted February 25, 2012 (edited) I can see, well, i calculated the coil with this two programs: http://www.daycounter.com/Calculators/Coil-Physical-Properties-Calculator.phtml http://pickups.myonlinesite.com/pickup.php?unit=mm&cl=63&cw=5&ch=3&bw=14&bt=1&ends=round&wd=0.2&id=0.22&show=on&avt=113&adj=ohms&avo=8 in the second program, it is very clear that the DC resistance is adjusted to 8 ohms however, in the first one, the resistance appears to be multiplied by 0.1, since it always shows something around 0.8 ohms as resistance, im not sure how that one works, but anyway, with any configuration i try, the result is always the same, around 0.8 the measures of my bobin: Width: 5 mm Length: 63 mm Height: 3 mm Number of turns: 113 impedance: 8 ohms Edit: im sorry i mistook the number of turns from 108 to 113, in fact, the number of turns, is 108 Edited February 25, 2012 by Sabudum Quote Link to comment Share on other sites More sharing options...
col Posted February 25, 2012 Report Share Posted February 25, 2012 I can see, well, i calculated the coil with this two programs: http://www.daycounter.com/Calculators/Coil-Physical-Properties-Calculator.phtml http://pickups.myonlinesite.com/pickup.php?unit=mm&cl=63&cw=5&ch=3&bw=14&bt=1&ends=round&wd=0.2&id=0.22&show=on&avt=113&adj=ohms&avo=8 in the second program, it is very clear that the DC resistance is adjusted to 8 ohms however, in the first one, the resistance appears to be multiplied by 0.1, since it always shows something around 0.8 ohms as resistance, im not sure how that one works, but anyway, with any configuration i try, the result is always the same, around 0.8 the measures of my bobin: Width: 5 mm Length: 63 mm Height: 3 mm Number of turns: 113 impedance: 8 ohms Edit: im sorry i mistook the number of turns from 108 to 113, in fact, the number of turns, is 108 You need to measure the actual resistance of the actual coil with a multimeter. Theory is great for designing stuff, it can tell you what should happen, but when the thing doesn't work, you need actual real world measurements to tell you what did happen. Measuring the coil's resistance will tell you if there is a short somewhere, or maybe if there is damage causing a much higher resistance. Quote Link to comment Share on other sites More sharing options...
Sabudum Posted February 25, 2012 Author Report Share Posted February 25, 2012 Perhaps, i'm gonna measure everything accordingly and post here if i find anything, thanks for your help, the problem is, i don't even have a multimeter with me, but i'm gonna borrow my friend's. Thanks again Quote Link to comment Share on other sites More sharing options...
DarkAvenger Posted February 26, 2012 Report Share Posted February 26, 2012 Hmm... Col is right about the resistance, my first try was a bit over 8ohms and didn't quite work well, so a multimeter is necessary. Just from the looks of things, you might try using just one of the cores for your driver, but I can't say for sure. I don't know if the coil would fit on just one, but it did look like it might. Just an idea, not the cause of the problem. 108 turns seems a bit low to me, I usually needed about 120 to 130 but of course it will be different for your exact bobbin. 0.2 mm or 32 gauge wire should be correct. Also, PVA or white glue should be used to pot the coil, this can be a big problem if done wrong which will decrease the efficiency of the coil. Efficency = less power, part pete's design. A buffer is necessary for the amp to be happy, here is a GREAT source of information on the subject http://www.muzique.com/lab/buffers.htm This also makes me curious as to your volume and gain controls. These are a VERY important variable as well, if both are full on and you gain is set to the highest(up to 200) your not going to get sustain. Gain is controlled by the resistance between pins 1 and 8, Volume is controlled by bleeding off some current to ground, it's usually a pot before the input to the circuit, pin 3 inverting, pin 2 non-inverting. Quote Link to comment Share on other sites More sharing options...
Sabudum Posted February 26, 2012 Author Report Share Posted February 26, 2012 Hmm... Col is right about the resistance, my first try was a bit over 8ohms and didn't quite work well, so a multimeter is necessary. Just from the looks of things, you might try using just one of the cores for your driver, but I can't say for sure. I don't know if the coil would fit on just one, but it did look like it might. Just an idea, not the cause of the problem. 108 turns seems a bit low to me, I usually needed about 120 to 130 but of course it will be different for your exact bobbin. 0.2 mm or 32 gauge wire should be correct. Also, PVA or white glue should be used to pot the coil, this can be a big problem if done wrong which will decrease the efficiency of the coil. Efficency = less power, part pete's design. A buffer is necessary for the amp to be happy, here is a GREAT source of information on the subject http://www.muzique.com/lab/buffers.htm This also makes me curious as to your volume and gain controls. These are a VERY important variable as well, if both are full on and you gain is set to the highest(up to 200) your not going to get sustain. Gain is controlled by the resistance between pins 1 and 8, Volume is controlled by bleeding off some current to ground, it's usually a pot before the input to the circuit, pin 3 inverting, pin 2 non-inverting. Uhum, i'm aware of all that, just what type of buffer would be best in this case? and how about removing once and for all the Gain pot, by replacing it with some resistor? is that a viable solution? although i never rev up the gain. Quote Link to comment Share on other sites More sharing options...
DarkAvenger Posted February 26, 2012 Report Share Posted February 26, 2012 This should work nicely as is. JFET could be J201, MPF102 etc. There are many, many tutorials on making guitar buffers, google might help you there. As for the gain pot, it's very possible to replace it with a resistor. Check the resistance of the gain pot when you have a working setup, then replace it. The reason this isn't a standard value for everyone is because everyone does not have the same guitar with the same pickups. A trim pot will allow you to hone in on the best value for you, then you could install the circuit and just forget about it. The real question is what is to gain? My trim pots cost like what, $0.25 USD? If you have a breadboard you could try different value resistors but it seems like a lot of extra work. Quote Link to comment Share on other sites More sharing options...
Sabudum Posted March 5, 2012 Author Report Share Posted March 5, 2012 All right, i measured the coil resistance now, and it turned out to be 8.8 ohms, so, too high, maybe that's the problem? Would this give absolutely zero sustain? Quote Link to comment Share on other sites More sharing options...
DarkAvenger Posted March 5, 2012 Report Share Posted March 5, 2012 Yes, it's very likely. The ruby is designed to drive an 8ohm speaker, 8.8 is too high. The reason pete's design works is because of it's efficiency and that is it's elegance. It can also be it's 'downfall' in a way. It is very possible to DIY and many people have proven that, but any imperfections in the workmanship and attention to detail can and often seem to decrease this efficiency resulting a loss in performance. Personally, I've wound 5 coils now, and each one was an improvement over the last until I was satisfied with the result. For most people if not all, winding a sustainer driver is a new experience and and an unknown process, my first attempt potting the coil with white glue was less than a success. It might take a couple tries but white glue is extremely forgiving. My advise is to follow psw/pete's tutorial as best you can, and if you don't get the desired result he can help you troubleshoot or post here and I'll try to walk you through it. It can be complicated in a way because there can be quite a few variables, I don't know what you know about the subject or what your understand of the system is, so I'll start with the basics first. Quote Link to comment Share on other sites More sharing options...
col Posted March 5, 2012 Report Share Posted March 5, 2012 All right, i measured the coil resistance now, and it turned out to be 8.8 ohms, so, too high, maybe that's the problem? Would this give absolutely zero sustain? 8.8 ohms is a touch high, but you should still get some sustain on some of the strings, so I think the main problem is elsewhere. more questions: Are you sure you have the magnet positioned correctly - ie. with the poles vertically in line with the driver core? If you have accidentally put it at 90degrees, it will not work. Are you testing the driver by holding it in your hand as close to the strings as possible without touching ? Try it near the 12th fret - it will sustain more easily there. Have you tried reversing the polarity of the driver? Either reverse the connections, or turn the magnet over Once you have checked these out, the next thing is to suspect that there is a problem with your drive circuit, or the connection between it and the driver coil - e.g. are you sure all the caps - in particular the output coupling cap - are the right way round (correct polarity)? Double check that all the components have the correct value. swap out the LM386 for a new one (you did use a socket?).. etc. If you have a breadboard/plugboard, build a new version of the circuit on the breadboard to see if you get the same results. cheers Col Quote Link to comment Share on other sites More sharing options...
col Posted March 5, 2012 Report Share Posted March 5, 2012 The reason pete's design works is because of it's efficiency and that is it's elegance. Gotta disagree there. The reason Pete's design works is because through an extensive process of trial and error, he homed in on a set of specifications that provide suitable electrical performance: The wire Pete specifies when wound to 8ohms around a suitable(!) core will produce a coil with an inductance value within a suitable range.The combination of this Inductance and DC resistance mean that the Impedance of the coil is fairly linear over the guitars frequency spectrum - only rising considerably at the point where you are playing higher up the neck so sustain is easier to generate (strings closer to driver, driver closer to belly of notes standing wave)The combination of output cap coil inductance and resistance generate a low Q resonant peak at or close to the frequency of the open high e string - the most difficult string to energize. the low inductance of the coil combined with the value of the output cap provide a phase relationship linear enough that phase lock can be achieved between driver and pickup without wasting too much power (assuming that you drive circuits phase response is compatible - big assumption). As far as build quality of the coil - yes that is crucial, but has nothing to do with the reason the design is successful. Any system of any design for any purpose needs to be manufactured to a reasonable standard or it won't work. Assuming the coil is reasonably well made, the really important factors in getting Pete's design to work are - the combination of core material and winding wire give you an inductance close to the inductance Pete gets (whatever that is). The circuit you use has similar phase response to the circuit Pete uses (whatever... you get it). So there are some unknowns that cannot be solved other than by trial and error. try using different core materials, different magnets etc. Try a different circuit - it may have a more suitable phase response... mustn't forget that the guitars setup - action, strings, pickup - can have a big impact on success. The main thing is though, that if you're in the ballpark, you will get some sustain on some strings - even with a slightly shoddy coil, a fetzer/ruby, and a non-ideal core (The difficulty is getting from there to a nice system with a strong even response and reasonable battery consumption.) So I'm thinking that there is something more fundamental wrong with the Sabudum's project. cheers Col Quote Link to comment Share on other sites More sharing options...
Sabudum Posted March 5, 2012 Author Report Share Posted March 5, 2012 All right! That helps a lot, i tried reversing the coil polarity, and the magnet is placed correctly, i could make the low E string sustain now, but only that, other strings won't sustain, and i've already tried rebuilding the entire circuit with new parts, still the same result, i'm gonna try with the buffer now, and see if it improves something, i'll post the results here as soon as i can. Thanks for the the help, everyone, especially you Col. Quote Link to comment Share on other sites More sharing options...
col Posted March 5, 2012 Report Share Posted March 5, 2012 All right! That helps a lot, i tried reversing the coil polarity, and the magnet is placed correctly, i could make the low E string sustain now, but only that, other strings won't sustain, and i've already tried rebuilding the entire circuit with new parts, still the same result, i'm gonna try with the buffer now, and see if it improves something, i'll post the results here as soon as i can. Thanks for the the help, everyone, especially you Col. No problem. If you are getting some sustain on the lower strings, then a buffer is likely to help - it will prevent 'tone sucking' ie. roll off of higher frequencies due to the input of the circuit loading(whatever that means) the guitars pickups. Quote Link to comment Share on other sites More sharing options...
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