psw Posted November 2, 2006 Author Report Share Posted November 2, 2006 If it works well it will prove to make it in SMD along with the amplifier, with printed circuit of double slide, to occupy the minimum space, and it will use commutators of which take walkman them, very small, to mount it everything in the conductor, not to have as soon as to modify the good guitar that I have she is one jem 555 of ibanez and the truth I do not want to touch it until not this all perfect one and with the minimum possible modifications. Yes...you can make the thing smaller...maybe even make it into the driver...but this thing will have to modify the wiring at least of any guitar... The mid-driver in a way presupposes that there is a mid coil pickup to replace and even then, the selector switch would need modification to substitute the mid coil options for others...(there are some neat options like both together and series/parrallel and phase that more than make up for it)... Since modifications are necessary like this it is debatable whether all circuitry is best installed in the guitar and the power supplied remotely (from a strap battery pack perhaps, or from a pedal board via a stereo lead) rather than some mounted extra hardware or strap pack with permanent wiring to the driver... Unless there is something I have missed in the way this could be approached...I will be looking into the ebow thing and if something that operates outside of the guitar's signal chain has any legs to it... There are other interesting things about the ebow that could be looked into, like the docking miniture ebow idea that was talked about a few pages ago...perhaps there is some use for that Hex technology after all... pete Link to comment Share on other sites More sharing options...
zfrittz6 Posted November 2, 2006 Report Share Posted November 2, 2006 (edited) If estube watching the one of ebow and also I already think that it can be a good idea. There are also small batteries with enough capacity and I believe that they are possible to be mounted in guiotarra taking advantage of all the hollows possible and with a connector to recharge them. also I am trying another type of conductor so that the cords of the guitar move ariba down and, instead of inside it go, to see that it seems to you. Edited November 2, 2006 by zfrittz6 Link to comment Share on other sites More sharing options...
psw Posted November 2, 2006 Author Report Share Posted November 2, 2006 zfrittz6...I can't see that, it is too small...can you make it bigger? pete Link to comment Share on other sites More sharing options...
zfrittz6 Posted November 2, 2006 Report Share Posted November 2, 2006 I feel much not to be able to enlarge it, but I explain to you, is like the fine conductors, single who irian projections right between the cords with different polarity, therefore aprovecharia the magnetism of both extreme of the coil, simultaneously that tirarian upwards and downwards of them. As I can put images but great, nonencounter the form to do it? Also I am investigating Frequency controlled gain amplifiers Link to comment Share on other sites More sharing options...
col Posted November 2, 2006 Report Share Posted November 2, 2006 (edited) That so the circuit proposed by curtisa with lm 324 goes?. If you mean the edn.com circuit that I suggested and Curtisa tweaked to work for his setup, I would wait a while. That circuit is not fully tested - I for one could not get it to work, it also doesn't really provide any great advantage over the LM13700 circuit I posted ages ago. I feel this could and should be improved apon. I have a version of the edn.com circuit very similar to curtisas that works using a J201. I also have a similar circuit using the fet setup from the 'fast FET limiter' in the op-amp feedback instead of the one curtis used... this has the advantage of more linear frequency response and much faster attack and release times. However it is more complex and anyhow, there are a number of things about this general approach that are not ideal for the sustainer: The main problem is that the level of the driver signal is directly linked to the threshold of the compressor - depending on how you set up the stages of the circuit, either the drive increases as you increase the threshold, or the response to low level signals decreases as you increase the threshold. Neither of these results are ideal - the drive signal should be nice and strong for _any_ signal less than the threshold - it's the weaker string/fret combos that need the most drive. It is possible to tweak the circuit to partially provide this effect, but then you lose a lot of flexibility in control of the threshold(s). So far, I have a couple of ideas to achieve my theory of using seperate low and high gates with heavy compression (or a comparator for square wave), but these both need a circuit that is too complex for us. I'm still trying to get somthing simpler. Unfortunately, I may be on my own with this as no-one else seems to 'get' it, or at least believe that it is important. I may need to do some studying so I can try using discrete transistors where applicable to reduce the size of the circuit B) Anyone have a discrete circuit for a 'bad' window detector that has a 'soft' switch over from high to low ? Basically, I want the effect that designers of comparators have been battling to remove for decades... wouldn't you just know it The truth is that for this project it is necessary to modify enough the guitars, unless utilizemos some box outside her, for the batteries and the circuits, I have been able to put it everything in the guitar who I have bought for this project, which me 100 cost €, and have had it to modify completely to put the batteries, hollowing the wood, and the amplifier hize in smd and I have the conductor along with. Yes, if you are getting involved at the 'development stage', you would be best to have a guitar dedicated to the sustainer that you are happy to 'customise'... Maybe when/if the system gets finalised, it would be poissible to club together and order a bunch of miniaturised smd circuits from a factory/manufacturer... cheers Col Edited November 2, 2006 by col Link to comment Share on other sites More sharing options...
zfrittz6 Posted November 2, 2006 Report Share Posted November 2, 2006 I believe that podria to solve many problems to us, if the frequency becomes tension this can control the gain of the amplifier, for it I am watching some c.i like lm2917, TA8029S ta7715 etc. Link to comment Share on other sites More sharing options...
col Posted November 2, 2006 Report Share Posted November 2, 2006 I believe that podria to solve many problems to us, if the frequency becomes tension this can control the gain of the amplifier, for it I am watching some c.i like lm2917, TA8029S ta7715 etc. There may be some misunderstanding about what I mean when I say the frequency response is not linear with some of these circuits. The frequency response of the amps is fine. The issues is that the compression level and threshold can be effected partly by frequency. It is possible to avoid this without using extra filter stages. As far as using multiple amps each aimed at a different frequency band, this may allow control over effects like 'harmonic mode', but is unlikely to give us noticable improvements to the basic circuit. It is impossible to seperate the problem areas of the neck from the over responsive ones through frequency (unless you use a fully hexaphonic approach). e.g. High E string first fret has a very poor response - so you would want to boost it... G string 10th fret and D string 15th fret are VERY responsive - so you want to attenuate them - but these are the all the same note So you can't use frequency band seperation to balance their amplitude... My suggestion (ages ago) of using two seperate frequency bands was purely to provide better driver response (not better string/fret balance) - i.e. a custom woofer driver and a custom tweeter driver... this could possibly allow for better efficiency and/or smaller drivers... but it probably wouldn't give enough of an advantage (if any) and would require a lot of R&D - not to mention more complex circuitry (crossover etc.) Col Link to comment Share on other sites More sharing options...
psw Posted November 2, 2006 Author Report Share Posted November 2, 2006 I'm still trying to get somthing simpler. Unfortunately, I may be on my own with this as no-one else seems to 'get' it, or at least believe that it is important. Col I certainly get the intention, just not much help with the execution details!!! Once people have this system on a playable instrument they will find that the response is uneven over the fretboard with any kind of height in the action and independant of frequency. Whether the commercial units suffer from this I don't know? A low action and effective driver addresses it, but not cures it and even brings their own problems (fret rattle, etc). It is interesting that with so much early concern for frequency compensation of phase differences and the like, AGC should have emerged as such a worry and such a difficult nut to crack. Anyone have a discrete circuit for a 'bad' window detector that has a 'soft' switch over from high to low ? Basically, I want the effect that designers of comparators have been battling to remove for decades... wouldn't you just know it I wonder what they used before IC's to make substandard comparators? Perhaps history holds some keys to this. Otherwise, how is AGC addressed in the Hoover/Osbourne and Floyd Patents...are they in alignment with your ideas? Yes, if you are getting involved at the 'development stage', you would be best to have a guitar dedicated to the sustainer that you are happy to 'customise'... Maybe when/if the system gets finalised, it would be poissible to club together and order a bunch of miniaturised smd circuits from a factory/manufacturer... For sure, but it will be a while before such a complete system is developed...I would still like to see, and may well do...a basic amp/pre kit in modular form that could be added to to get more involved with the experimentation process...having one does add to the incentive of people to develop it further and better understand the problem at hand... A separate "sustain box" approach could help also to encourage people to get involved that do not want to physically modify a guitar, yet are comfortable with changing wiring and such (after all you do need soldering skills and such to build the thing anyway).... As for compensation of string tension my thin core driver does address the issue a little by having less efficiency on the bass strings than could be achieved with a wider core...it has it's own built in bias to higher frequencies...A bi-lateral stereo driven device, could also achieve the woofer/tweeter effect also...there are a multiple of driver tweeks that could address this, but not the action issue... In that regard, all I can suggest is that the further toward the bridge that the driver is moved, the less variation in string height over the driver with fretting caused by action. Another reason to aim for a mid driver in my mind... Perhaps there is a way of achieving a bridge driver to eradicate the problem completely... One of the big deterents in conventional thinking was that it was assumed that the ideal location of the driver was around the 24th fret as it was situated at the most elastic part of the string (at it's centre) and had a less complex harmonic structure and tension. The realitiy is that the tension is the same over the whole of the string and that the device responds very well at higher frets where the length from the fretted note to the driver is very close... I can only assume from this that, if it were practical, a bridge end driver would work (and some Hex experiments showed this to be true, but difficult (perhaps for other reasons?))...a mid driver could be a happy comprimise that provides other benefits as far as installation and such... Perhaps there are some radical solutions in the ebow approach of sourcing the signal from it's own pickup. One thing that comes to mind is a bridge end driver sourced from a piezo system in the bridge...you will recall that on an electro acoustic, curtis was able to drive the strings all along thier length... Further experiments need to be conducted as to how a driver in such a system, permanantly placed would interact with the bridge pickup...my early work was a little discouraging in this regard BTW. A DIY version could be achieved with a simple buzzer piezo while more sophisticated options would exist for systems like the ghost saddles or the Line 6 guitar... I know such "visions" are a little too forward thinking at this stage, but take it as brainstorming for other approaches to the problem that col is trying to address that really is an issue worth pursuing...good luck col, you are not alone....do,do, do,do, dooooo... pete BTW even making it bigger, I still can't see or read this...any chance of making it bigger zfrittz6 Link to comment Share on other sites More sharing options...
curtisa Posted November 2, 2006 Report Share Posted November 2, 2006 Good stuff...so are there pics of this thing?... There are now. Ladies and gentlemen, I present to you "The Bastard": . The pickups are nothing special, just the ones that came with the body. Stock Yamaha's I guess. The single coil has the driver wound on top, like Pete's stacked coil driver. Hardware is all Gotoh. Sorry, I don't have a closer picture of the sustainer - I'll try to take on or two over the weekend. It's a 3mm-wide steel blade with an arched top to match the curvature of the strings. The blade just replaced the original 6 pole pieces. Got the beastie working last night, amid a tangle of wires and aligator clips. With just a simple JFET buffer feeding the LM386 it actually works better than it ever did with a similar circuit with the driver held in my hand over the strings of my test guitar. Go figure One thing I have to do though in order to keep the whole thing stable, with the sustainer engaged, I have to short the single coil pickup wires together, otherwise the whole thing erupts into mad feedback. Still, with the sustainer working I have fundamental and harmonic mode almost perfect as-is. Yes, if you are getting involved at the 'development stage', you would be best to have a guitar dedicated to the sustainer that you are happy to 'customise' Based on the differences I've just experienced in holding a driver in my hand over the guitar strings, versus installing a driver permanently in a guitar, I'd say it's mandatory. All the circuit experimentation that I've been working on almost seems wasted as I can get almost perfect operation with a stupidly simple circuit, without any super preamps and compressors. That's not to say that there's no room for improvement though That so the circuit proposed by curtisa with lm 324 goes?. Don't build it just yet. While I have built it, tested it ,and got it working, others have not been so successful. And the improvement I've experienced just in permanently installing the driver into the guitar makes that circuit seem like overkill. Battling on... Curtis Link to comment Share on other sites More sharing options...
col Posted November 2, 2006 Report Share Posted November 2, 2006 (edited) Good stuff...so are there pics of this thing?... There are now. Ladies and gentlemen, I present to you "The Bastard": congrats - looking really good That's not to say that there's no room for improvement though ......... the improvement I've experienced just in permanently installing the driver into the guitar makes that circuit seem like overkill. Yep, installing it makes a big difference. As we have discovered, some guitar setups work better than others with just the basic circuit, how is your high E string on the lower frets? Another question, what is the current drain like ? cheers Col Edited November 3, 2006 by col Link to comment Share on other sites More sharing options...
psw Posted November 3, 2006 Author Report Share Posted November 3, 2006 Fantastic... Got the beastie working last night, amid a tangle of wires and aligator clips. With just a simple JFET buffer feeding the LM386 it actually works better than it ever did with a similar circuit with the driver held in my hand over the strings of my test guitar. Go figure One thing I have to do though in order to keep the whole thing stable, with the sustainer engaged, I have to short the single coil pickup wires together, otherwise the whole thing erupts into mad feedback. Still, with the sustainer working I have fundamental and harmonic mode almost perfect as-is. Yes...you see...it is not untill this stage that you know what you are working with and the real problems are...you can imagine how I felt when I connected it up and had to find a way to bypass the pickups on my crazzy wired three pickup strat with single coils...but it can be done The installation of the driver close to the strings, below them, helps a lot, especially with EMI but if it doesn't work holding it above the neck, it certainly wont in a full install like this... Yes..."almost perfect as-is"...that is certainly the first impression...it certainly is a usable and interesting instrument in this simple form. You will find limitations and work arounds and all kinds of techniques and limitations, but it certainly does work...doesn't it! All the circuit experimentation that I've been working on almost seems wasted as I can get almost perfect operation with a stupidly simple circuit, without any super preamps and compressors. That's not to say that there's no room for improvement though Absolutely...an now you will be able to tell the extent to which such improvements need go and what those improvements need really be. Also, you may find other ways of approaching it and things you wish that the instrument could do... What col is working on with the AGC...or perhaps what I am endevouring or suggesting be done by moving the driver closer to the bridge will make it so much better...there is a need for a more even and predictable response across the neck and to accomodate a higher action, especially with the 10 guage strings... You will also find that the sustainer encourages a change in your playing style. Damping of course will be important...but I found that it made me play more along the strings and that I used the tremolo far more to manipulate pitch than bending. Slides and a light touch produce a more rewarding "bloom" to notes too... You may find that musically you draw influence from other instruments that are capable of such sustain or blown effects like woodwinds and strings...I found that there is an eastern ethnic influence effecting my playing...if nothing else, it's a bit of a rut buster and can of course still do everything that a guitar does anyway so well, without changes to technique...so it's all gravy! ---- I am going to blow my own horn here a little... This device as I have put it...thin coil, thin core driver, 0.2mm wire...is simple but took a long tome to reach this point. From the very first I was able to sustain a single string but it took a long time to get to a practical working formula and concept for others to follow. The devil is in the details, as always. But the more I added to the concept...the year I spent pursuing the Hex ideas and avoiding coil winding for instance...the more difficult it became. In the end it is simple, but without doing the Hex things which was to miniturize the thing, without looking into surface mounting the device, without seeking to retain the neck pickup and without looking for solutions in electronics...I would likely not have arrived at this point...as obviously other had not either... What I would most likely have done is to try an emulate to some extent the structure, size and shape of conventional pickups...and run the same problems that others had come across in doing so. The morals of this is that...with perserverance, things can be achieved...that there is still more that could be done...that simple solutions may be found but it may take the long way around to discover them...and that the thing will work in it's most basic form satisfactoraly (if not exactly perfectly) if you do follow the formula that I devised and do it well (as curtis has found out)... I can't tell you how happy I am that another sustainer based on my model is achieving much the same results...now of course I will want to hear the thing... It should serve as further encouragement to know that it can be done (although perhaps only in Australia!) and that performance of a reasonable standard can be achieved... Perhaps I should be content with that as a DIY project... pete Link to comment Share on other sites More sharing options...
zfrittz6 Posted November 3, 2006 Report Share Posted November 3, 2006 Then, to have if I find out to me, that the translators I do not end to find out very well that it is what looks for, I create to understand that what we needed is a type of compressor - limitor that acts with the signal before the amplifier, to cogovern if is thus. if this is thus what we needed is a control that acts on the amplifier but controlled by the signal of the harvesting. is this thus?. Link to comment Share on other sites More sharing options...
zfrittz6 Posted November 3, 2006 Report Share Posted November 3, 2006 that so this previous one with ALC to make level the signal level? , it can work? , or somebody can simulate it. Basdo in developed integrating for cassette recorders, which includes in its tablet circuits of automatic control of level, is able to make level a signal of audio without concerning its original level. Link to comment Share on other sites More sharing options...
psw Posted November 3, 2006 Author Report Share Posted November 3, 2006 if this is thus what we needed is a control that acts on the amplifier but controlled by the signal of the harvesting. is this thus?. Yes...this is what we need...I will have to leave it to the experts to figure out if this chip can do it though. Certainly there are a lot of chips with ALC built in for tape recorders and mobile phones, mostly in SMD however...this 14pin DIP is interesting, and I see I have looked at this before too...here is the TDA7284 Data Sheet...how many watts is this BTW? all the circuit is basically doing is sending a variable pulse to the driver coil so that the guitar strings vibrate, it will also work better on strings already vibrating so that will maybe cut down on likelyhood of strings starting to vibrate when you dont want them to laugh.gif i am good at digital electronics so i am trying to create a small digital circuit that works, thats all. the way i see it, all you need to do for sustain is to keep the strings vibrating, if keep them vibrating then you keep the sound going and therfore get sustain, although you cannot get some of the tricks like sustain that automatically gives you the harmonic of the note fretted (like fernandes sustainers) bookread.gif the circuit i have designed gives a few fresh ideas like being able to change the speed and strength of the pulses, effectively giving you a weird kind of volume/decay control Ah...I am not sure if this is going to be effective...I am particularly concerned that you will get a pulse signal from the clock induced in the guitars pickups. If you want a pulse signal that follows the guitar strings frequency, the easiest way is effectively a fuzz circuit...a clipping amp, which is very easy to do! Also, this is likely to have problems with understanding any polyphonic sounds (ie chords) but is worth a shot... What would be good with digital is a means of doing the switching for this device...the bypass switching on my guitar uses a 4PDT switch which is bulky and expensive just to turn it on! Functions like momentary switching of the device, the bypassing and other functions would be highly desirable...but the size of the circuit still needs to be kept small...you are the first to put their hands up to understanding digital! There may well be other digital solutions too...but we are working in an analogue world and in the end will need to drive the analogue string to achieve sustain. If there were a digital solution, it could become complex...any delay in the A/D D/A conversion could cause phase problems... Perhaps there is a digital way of controlling compression, I don't know but it sounds complex and bulky... There is a growing emergance in digital in terms of the guitar (modeling and such) and it is worth your experimentations just to get an introduction to this field...there are some amazing technologies coming out... I am from the era where we slowed down records to practice and learn...I just bought a cheap MP3 player for my daughter that will slow down tracks without altering pitch. I also recall someone using video tapes to record quality backing tracks for a cover band (pre CD)...now this tiny device could hold hours of such tracks, easily accessable and potentially mounted on a guitar replacing half a car load of equipment (and that was only 20 years ago!) I am not sure about the digital sustainer (unless you want to go a sampling route, and perhaps there is some posibility with all the cheap sampling devices available these days) but am certainly encouraging your experimenting and brainstorming of ideas here...welcome again... pete Link to comment Share on other sites More sharing options...
da_free_runner Posted November 3, 2006 Report Share Posted November 3, 2006 jus been reading this post, s*** its long!!!! another idea i am working on is a microphonic sustainer actually modded INSIDE a humbucker. im using a tiny peizo speaker fitted in the middle of underneath the coils and it is barely noticeable. i cant wait to see if it will work, i just need to build a little amp circuit for it the will go sumwhere ile let u no how it goes Link to comment Share on other sites More sharing options...
curtisa Posted November 3, 2006 Report Share Posted November 3, 2006 Yes...this is what we need...I will have to leave it to the experts to figure out if this chip can do it though. Certainly there are a lot of chips with ALC built in for tape recorders and mobile phones, mostly in SMD however...this 14pin DIP is interesting, and I see I have looked at this before too...here is the TDA7284 Data Sheet...how many watts is this BTW? None, it's just a preamp You'll still need a power amp IC to drive the sustainer. It's a bit of overkill too - probably not much use for us as a stereo IC with the tape bias selection stuff. Also, the ALC control is feedback, not feed-forward. Have a look on page 8 of the datasheet, you can see how the control voltage for the ALC is derived from the output from the circuit, not the input. Not a bad idea though, it'd be near perfect if we could find a single-channel, self-contained preamp/feed-forward ALC chip with a wide supply voltage tolerance. Keep searching! all the circuit is basically doing is sending a variable pulse to the driver coil so that the guitar strings vibrate, it will also work better on strings already vibrating so that will maybe cut down on likelyhood of strings starting to vibrate when you dont want them to laugh.gif i am good at digital electronics so i am trying to create a small digital circuit that works, thats all. the way i see it, all you need to do for sustain is to keep the strings vibrating, if keep them vibrating then you keep the sound going and therfore get sustain, although you cannot get some of the tricks like sustain that automatically gives you the harmonic of the note fretted (like fernandes sustainers) bookread.gif the circuit i have designed gives a few fresh ideas like being able to change the speed and strength of the pulses, effectively giving you a weird kind of volume/decay control Ah...I am not sure if this is going to be effective...I am particularly concerned that you will get a pulse signal from the clock induced in the guitars pickups. If you want a pulse signal that follows the guitar strings frequency, the easiest way is effectively a fuzz circuit...a clipping amp, which is very easy to do! Also, this is likely to have problems with understanding any polyphonic sounds (ie chords) but is worth a shot... No, I think Pete is right. I don't think this'll work. Apart from the digital pulses being induced all through the guitar circuitry getting into the audio output (particularly when you're running it through a high gain amp), to get optimum performance you'd need to "ping" the sustainer at the same frequency as the string that's currently being played, requiring an input source from one of the pickups and extra circuitry to extract the fundamental frequency from the string and use it to clock the pulse generator. And as Pete rightly points out, it'd never work with with chords and evolving notes, at least not without a lot of complex circuitry and probably a polyphonic pickup. What would be good with digital is a means of doing the switching for this device...the bypass switching on my guitar uses a 4PDT switch which is bulky and expensive just to turn it on! Functions like momentary switching of the device, the bypassing and other functions would be highly desirable...but the size of the circuit still needs to be kept small...you are the first to put their hands up to understanding digital! I've actually devised a switching arrangement for my sustainer that does all the necessary pickup bypassing and sustainer on/off control using just 1 DPDT switch I just need to double/triple/quadruple check it to make sure it all works properly and I'll post a diagram of how I did it. It could solve the problem of the popping driver when turning it on and off too In a nutshell, the key is to switch the battery -ve and earth, not the battery +ve - I'll leave you to stew on it for a day or two I am not sure about the digital sustainer (unless you want to go a sampling route, and perhaps there is some posibility with all the cheap sampling devices available these days) but am certainly encouraging your experimenting and brainstorming of ideas here IMHO, In the interests of keeping the sustainer within reach of most of us with some practical construction abilities, I think we should keep the sustainer in the simple-as-possible basket. Doesn't mean we can't pursue the digital route, but at the moment the analog (LM386, FET buffers, opamps etc) system is certainly a lot easier to build and run. Although, if you've got a new idea going, by all means try it out and let us know how you're going with it I guess we also need to decide if we're devising a system that anyone could build from scratch by themselves, or if we're developing a fully-tested product that could be sold as a DIY kit, so the end user only has to put it all together. If it's the former, simpler probably equals better. If it's the latter, anything goes (digital, analog, mixed signal, DSP, embedded CPU etc), but it does mean that we have to do a lot more R&D before we can reach a failsafe solution for anyone to purchase and use. Cheers, Curtis. Link to comment Share on other sites More sharing options...
da_free_runner Posted November 3, 2006 Report Share Posted November 3, 2006 lol wel taht didnt work, the peizo doesnt generate enough sound to feedback the pup, im now trying a cheapo wen chuang speaker i found thats only about and inch across and very thin, it seems to work alot better already but i havnt fitted it into the guitar yet so wiat and see Link to comment Share on other sites More sharing options...
psw Posted November 3, 2006 Author Report Share Posted November 3, 2006 Welcome da_free_runner What you are doing is the infamous "Ansil Sustainer Mod" discussed here at length some years ago...it may not do what you think it does...and yes I have extensively worked on this and it does not produce the infinite sustain of a sustainer... It is more of a distorted, microphonic feedback compression type of effect...if you can get it to work at all...what it does is generate a signal within the windings of the pickup itself...not actually drive the strings themselves (more the pickup)... No harm in trying though...it is actually in researching the sustainer that I came across this and found Project Guitar and this whole thread got started... Ah...here we are, second post on the thread!!! here is the actual original article...Ansil's Sustainer Mod Link You will find many a thread here where people have tried and failed or been unsatisfied with the results as well as some discussion as to how/if it works and what it is supposed to actually do... Ansil himself actually used a headphone under the pickup and this will make the effect more prominant, but it doesn't actually move the strings at all...it is an effective noise maker though!!! Hope that isn't too disappointing, and as I say, it is an introduction to sustainers of a sort...but think about it, at best you will be shaking the pickup, not the string and although you may think that the string will move with the magnetic field of the pickup, you will find this not so I am afraid...and this is the only potential mechanism for infinite sustain...of the kind associated with a "magnetic sustainer" or even an "acoustic sustainer"... That is not to say that the magnetic sustainer need only be the only way to achieve the results we want, or that my way is the best or only way... This thread has gone for a long time and you will find that I have built a lot of crazy things in this quest...including making bridge saddles with piezo elements so as to attempt to vibrate the strings...using piezos to vibrate high powered neodyminium magnets and a lot more besides... Most of these things were nt documented as they failed so miserably... other's showed some promise (a speaker in the tremolo springs, for instance...but not enough! If you think about it, you will need a LM386 or equivilent and a preamp to prevent loading (eg a fetzer/ruby) anyway...the only thing you have really saved yourself is the need to wind a driver (10 mins of winding), so if you do try this and it is not up to expectations, all is not lost as you could wind a driver and get a working guitar like curtis has just described... Anyway...welcome aboard and report back on your results... pete Link to comment Share on other sites More sharing options...
da_free_runner Posted November 4, 2006 Report Share Posted November 4, 2006 yes i hav tried a few of these ideas before, without too much success, i need a very powerful amp to get anything, i thought i would give some of these ideas on the forum a shot anyway to see if i could modify them to suit. i have been talking to one of my tutors at college about this idea and e suggested i modify a humbucker so one coil is the driver and the other a single coil, we have created mockup diagrams for a small circuit that will run off a 9v battery and i am currently working to iron out some glitches on it, it is based around i 555 timer chip and i have built and simulated the cicuit in a virtual enviroment with promising results, i will post diagrams when we have sorted the glitches, but i think it may interest some people on this thread as it allows you to shape the signal that goes to the driver coil to create more varied sustain effects. will Link to comment Share on other sites More sharing options...
da_free_runner Posted November 4, 2006 Report Share Posted November 4, 2006 thought i would add this its not the full circuit as its abit more compicated, but this circuit was tested for my college 2nd year HND project and it works perfectly althought i have not used this circuit in my final design. the pot by the 555 timer controls the speed of the pulses the timer gives off, the pot above the opamp controls the size of the pulses giving you full control of the square wave output meaning you can actually create a sustain and then use a pot on the guitar to make it gradually decay and then maybe build up again the box marked latch is basically a switch that grounds the signal going through the transistor so cutting the sustain, which means you can turn the sustain unit on by a switch or a pull/push pot, that could also at the same time turn the power to the circuit on and off, the amplified pulses drive the driver coil causing it to vibrate the strings this does work, it has been TRIED AND TESTED just not with guitar strings neway fingers crossed i hope to have this circuit debugged and even built by the end of wednesday Link to comment Share on other sites More sharing options...
col Posted November 4, 2006 Report Share Posted November 4, 2006 thought i would add this ... its not the full circuit as its abit more compicated, but this circuit was tested for my college 2nd year HND project and it works perfectly althought i have not used this circuit in my final design. ... Very interesting, although its not what most of us are building... seems like some sort of synth idea - if you could midi it up so a keyboard could select the timer frequency, then you could play the guitar with a keyboard . Unfortunately, when the note you play isn't a note or harmonic of a note being fretted on the guiter, it is unlikely to work. What most of us are working on is a system where the frequency of the driver signal is the same as the frequency of the note the guitar strings are playing.... so when you pluck a string or chord, that frequency is used to drive the sustainer. We basically use the amplified pickup output to feed the driver. AFAIK the only way to get enough drive from a battery is to use positive feedback in this way - the driver signal frequency must match the note frequency so the level can build up via the feedback. Col Link to comment Share on other sites More sharing options...
da_free_runner Posted November 4, 2006 Report Share Posted November 4, 2006 (edited) all the circuit is basically doing is sending a variable pulse to the driver coil so that the guitar strings vibrate, it will also work better on strings already vibrating so that will maybe cut down on likelyhood of strings starting to vibrate when you dont want them to i am good at digital electronics so i am trying to create a small digital circuit that works, thats all. the way i see it, all you need to do for sustain is to keep the strings vibrating, if keep them vibrating then you keep the sound going and therfore get sustain, although you cannot get some of the tricks like sustain that automatically gives you the harmonic of the note fretted (like fernandes sustainers) the circuit i have designed gives a few fresh ideas like being able to change the speed and strength of the pulses, effectively giving you a weird kind of volume/decay control also, i can see what you are saying about maybe being able to play the guitar with a keyboard via a kind of midi setup, you could probably control which strings vibrated if you altered the waveform to a certain frequency, as with on a sitar (is that how you spell it?) which has extra sympathy strings that vibrate in sympathy with the string being plucked (if you pluck a string, the sympathy string for that note begins to vibrate aswell as it is at the same frequency) so it would be possible to create some kind of midi interface if i added some more circuitry, and i will not rule out that idea as a possible sidetrack project after i have perfected my prototype sustainer, as i am very interested in midi after seeing the guitars hugh manson created for matt belamy of muse, some of which incorporate midi controllers including a midi strip and even a x-y pad that can control effects such as the korg kaoss pad Edited November 3, 2006 by da_free_runner Link to comment Share on other sites More sharing options...
psw Posted November 4, 2006 Author Report Share Posted November 4, 2006 Nice Post curtis... No, I think Pete is right. I like to say that "yes, pete is right"...but then I would! Not that early on I and others did suggest/discuss similar things...anything goes really, and it is how we learn and things develop...doing something that doesn't work teaches you more and points you in other directions you may not have gone if R&D is your thing... I guess we also need to decide if we're devising a system that anyone could build from scratch by themselves, or if we're developing a fully-tested product that could be sold as a DIY kit, so the end user only has to put it all together. If it's the former, simpler probably equals better. Well...I think we are having a lively discussion on all things sustainer in the end...exploring the ideas and stretching them a little further with the resources we can muster...Is there an adgenda? Simpler always equals better...if it gets the job done... Some complexity is required if you want to do something more refined and simple is not always as simple as it may appear... I have made probably 60 different types of drivers...the thin coils came from the hex system compact direction, the 0.2mm wire from trial and error. Don't think though that I didn't try other wire guages or deeper coils...these things don't just happen! The end result is simple, but specific for my design...it is the specifics that can be complex...if you get what I am saying... My current thinking about a mid driver is an attempt to solve a few problems...it does however pre-suppose a mid pickup I guess, but as the S-type guitar is the most popular, it shouldn't be too much of a deterent. A mid driver may mean the loss (certainly in sustainer mode) of the mid pickup, but this is typically the least used...you still retain the two most diverse and widely used sounds, neck and bridge...and you can use other positions on a selector to explore other sounds like combinations, phase and series parrallel options if you need more diversity. If one can stand the loss of the mid pickup the driver will be able to be compact and so allow for different design ideas and possibly internal circuitry...even without resorting to SMD's. The other thing I hope it will address is what is being looked at electronically by col and curtis in regards to action compensation...being closer towards the bridge, there is less movement of the strings towards the driver while fretting than at the neck (it won't solve the problem, but will address it to some extent). Another interesting development is the ability to drive the sustainer from different source pickups...this should also achieve a variety of different responses from the device. But this will not be easy to achieve...the answer I hope will be simple, but I have recently been somewhat ill at ease about the rail driver's performance...I will just have to try it and a few other ideas to see what is most effective for the application...it could well be that a stack approach or a few other thoughts (deep magnets with shallow coils, for instance) may be as easy and even more effective. Tim's achievements in making compact epoxy coils will really open up the possibilities of taking my basic formula to the next level. I've actually devised a switching arrangement for my sustainer that does all the necessary pickup bypassing and sustainer on/off control using just 1 DPDT switch...It could solve the problem of the popping driver when turning it on and off too In a nutshell, the key is to switch the battery -ve and earth, not the battery +ve - I'll leave you to stew on it for a day or two Obviously I am very interested...I kind of see where you are going, but don't see how you achieve the bypass functions...a strat guitar can be especially complex of course... Why I keep bringing up digital switching is that you could provide switching (on the driver maybe) that would be very discrete and cheap (no hole drilling)...but mostly, I'd like to be able to add sustain and effects (harmonics especially) on the fly with a momentary or easy push on/push off control. I even devised a plan for a tremolo arm that had a twist grip to control the thing so that with a tremolo you could have control of both pitch and sustain in the one device...perhaps not DIY! The down side of course is the circuitry adds substatially to complexity and may be a lot bigger than the sustainer circuit itself...hmmm IMHO, In the interests of keeping the sustainer within reach of most of us with some practical construction abilities, I think we should keep the sustainer in the simple-as-possible basket. I concur, but as I said earlier, you may need to think large to get down to the essentials...then the result will seem ridiculously easy (like the thin coil design)! I'd like to get the project to a succinct basic amplifier circuit (I have never been completely convinced of the fetzer/ruby and have not used it myself, though it will do the job, as the "best" design for a standard circuit). A simple amplifier will do the job in it's own way. If you want more refinement, sustainiac and fernandes may well be the way to go. Too much complexity will only serve to make these products more appealing. We do seem to be inching ever closer however to what I am currently envisioning...a selfpowered mid coil driver with a simple preamp and switching simplified and installation more coherent and transferable from instrument to instrument. Extremely compact...already the DIY sustainer is smaller than the commercial units and potentially less invasive. Improvements in preamp circuitry (compression) may close the gap to make it the premier sustain device...even if you do have to DIY it! In short I am very happy about the progress by everyone at this time, a little unexpected and with very little practical input from me...a little humbling I must say! I really do encourage people like col to keep plugging away though...it is only through this work that the simple answers will be found and this will contribute to the device in subtle but important ways...ways not really addressed previously, and I suspect not addressed by the commercial designs either (anyone had a look at the patent's AGC yet?). Nothing simple comes easily it would seem...keep at it, and if nothing else, the commaradery of sharing ideas is worth the effort... pete PS...don't be put off putting forward ideas da_free_runner, zfrittz6 and others...take a leaf out of spazzy's book...he appears to have gone his own way with the outboard amplification, rail idea and very happy with the results. His input, though radically different in approach has achieved a result but has also really made people think more about dual coil drivers and the rail design in particular...even if his specific approach is not the presently pursued course...every contribution is a contribution... PSS...also, as we scream towards 70,000 visits I have to remark that this thread is getting a lot of hits. Guests should note that if they are following this, they are welcome to contribute ask questions or offer encouragement (and criticism I guess) and that even viewing the thread is an acknoledgement of the work of these guys. If you are not members, you may wish to join if only that the forum will notify you everytime a new post is added to the thread! Otherwise, I hope you are enjoying the banter and keep coming back for more. Link to comment Share on other sites More sharing options...
col Posted November 4, 2006 Report Share Posted November 4, 2006 *Note: I wrote this reply just after the Da_free_runner posted, unfortunately, there has been a problem with my forum account, so I couldn't post until now. I'm not trying to 'shoot you down' DFR, just want to help point out possible issues thay you may not have considered, and also to discover if I am misunderstanding the intention of your design. all the circuit is basically doing is sending a variable pulse to the driver coil so that the guitar strings vibrate. But it's a manually variable pulse that is independant of the frequency that the guitar is producing? it will also work better on strings already vibrating so that will maybe cut down on likelyhood of strings starting to vibrate when you dont want them to Are you sure? Assuming that each pulse is of the same polarity, it will push/pull the string the same way each time... with the string at rest, this will always exite it. with the string already vibrating at some arbitrary frequency, your circuit is as likely to damp the string as exite it further ! To help see this a good analogy is a swing in a playground... when you puch a child on a swing, you only need to give small pushes, the important thing is that the pushes are exactly synchronised with the natural frequency of the swing... What you are doing would be like sometimes pushing with the existing motion and sometimes against. i am good at digital electronics so i am trying to create a small digital circuit that works, thats all. the way i see it, all you need to do for sustain is to keep the strings vibrating, if keep them vibrating then you keep the sound going and therfore get sustain, Thats kind of a simplistic description, you missed a key point - yes it is about keeping the strings vibrating.... but the need to be kept vibrating at their existing frequency. Unfortunately, for your circuit to do this, you would need to manually adjust the frequency to somehow match the frequency of the guitars note. e.g. if your circuit was set to 200hz, and the string was vibrating at 300hz, then the drive circuit will only be in phase (helping) the string every 3rd cycle - so it will spend 2 thirds of the time either interfering with or completely opposing the desired vibration of the string. I suppose one thing would be to have the driver output short pulses at a much lower frequency - like tremelo picking.... This could work theoretically, although intuition suggests that it would have audible side-effects, and would require a _lot_ of energy behind each pulse... although you cannot get some of the tricks like sustain that automatically gives you the harmonic of the note fretted (like fernandes sustainers) bookread.gif the circuit i have designed gives a few fresh ideas like being able to change the speed and strength of the pulses, effectively giving you a weird kind of volume/decay control have you tested your system on a guitar ? I would be very interested to hear it working - say, sustaining natural guitar tones on a scale. I would also be interested to see what you could do with the approach we are trying to develop. You say that you are good at digital electronics... would you be able to develop a simple circuit that could digitise the driver signal and apply more controllable conditioning and AGC in the digital realm before using a class-T amp (or similar) to feed the driver ? What would be the minimum processing requirements to provide DSP for a usable mono signal? microcontroller? PIC? what would the current drain be like? how big would the circuit be? If you can get a circuit designed, I'd be happy to do the coding - I have plenty assembly language experience, some embedded (kind of) and some audio dsp knowledge. maybe there are existing off the shelf boards that would make this easy? just load in our custom dsp code and plug it in ? Col Link to comment Share on other sites More sharing options...
col Posted November 4, 2006 Report Share Posted November 4, 2006 We do seem to be inching ever closer however to what I am currently envisioning...a selfpowered mid coil driver with a simple preamp and switching simplified and installation more coherent and transferable from instrument to instrument. Extremely compact...already the DIY sustainer is smaller than the commercial units and potentially less invasive. Improvements in preamp circuitry (compression) may close the gap to make it the premier sustain device...even if you do have to DIY it! Hmm, I still get crosstalk fizz with the driver in the neck position - trying to put it in the middle position makes that issue much worse = totally unacceptable. It is probably related to the high power pickup i have in the bridge position, but that is how I (and MANY others) get the sound I like best. I really do encourage people like col to keep plugging away though...it is only through this work that the simple answers will be found and this will contribute to the device in subtle but important ways...ways not really addressed previously, and I suspect not addressed by the commercial designs either (anyone had a look at the patent's AGC yet?). 'plugging away' is exactly how it feels . Maybe when I get my hands on some vactrols, I might make a little new progress As far as the patents, I've purposly avoided looking at them closely - don't want to get too heavily influenced until we have exhausted all our own ideas. cheers Col Link to comment Share on other sites More sharing options...
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