Donovan Posted January 3, 2009 Report Share Posted January 3, 2009 I put together a BOM (adding the DPDT switch, some wire and a board) with vendor info for what I "think" are OK components. Would you guys please review it and comment on anything specific I might have wrong before I begin ordering things? I am particularly concerned with my potentiometer choices. Even some "yeah that component will work, but this is a better idea because it's one-third the size" type comments would be perfect! It may also help out others like me in the near future... this did take a few hours to sort through and although the costs may not be accurate as time goes on, the P/N's and such should help out at least and no need for each individual to have to start from scratch. BTW, tonight I also found that upon registering, you can request "samples" of LM386M-1 (SMT version), N-1 and N-4 from National Semiconductor. Going to bed now as it's about 4:00 am here. Cheers! Link to comment Share on other sites More sharing options...
mrjstudios Posted January 3, 2009 Report Share Posted January 3, 2009 I put together a BOM (adding the DPDT switch, some wire and a board) with vendor info for what I "think" are OK components. Would you guys please review it and comment on anything specific I might have wrong before I begin ordering things? I am particularly concerned with my potentiometer choices. Even some "yeah that component will work, but this is a better idea because it's one-third the size" type comments would be perfect! It may also help out others like me in the near future... this did take a few hours to sort through and although the costs may not be accurate as time goes on, the P/N's and such should help out at least and no need for each individual to have to start from scratch. BTW, tonight I also found that upon registering, you can request "samples" of LM386M-1 (SMT version), N-1 and N-4 from National Semiconductor. Going to bed now as it's about 4:00 am here. Cheers! I'll take a look at it for you a little later on. Any reason why you didn't buy all of the parts from mouser except the 32AWG wire? I'm pretty sure you can get everything from mouser, and at better prices. Also, I would not buy anything from radio shack... I got some parts from there for my custom tube amp, and when there were things wrong with the simplest of parts on the amp, it was the ones from radio shack that always seemed to be the problem.... Link to comment Share on other sites More sharing options...
Donovan Posted January 3, 2009 Report Share Posted January 3, 2009 I had trouble with finding the LM386 and an appropriate PCB from Mouser. The LM386's they have available are clones, something I did not want to risk without hearing of prior success. The PCB was chosen as I could see what I was getting on the website... Mouser's selection was broad, but not very visual in this area. Please do make suggestions. Thanks! Link to comment Share on other sites More sharing options...
psw Posted January 4, 2009 Author Report Share Posted January 4, 2009 (edited) The links don't work on the sheet unfortunately so I can't easily see these parts...i would get an 8 pin DIL for the chip perhaps...allows you to reuse it easily (funny how the entire power amp is only $1...modern electronics)...possibly a spare Jfet (easy to be damaged) and some socket strip so that this can be inserted without soldering for reuse and prevention of damage through static or heat. The Pots are for the second scheme I am guessing, but you may find that the two outboard pots excessive and impossible to fit into your strat...you are going to need a battery snap or something (and consider how you would get a battery into the guitar where you can get to it...under the scratchplate on a strat is not suitable...the battery will go flat fairly fast....we are running a poweramp at max gain here! My preference would be to run with the first layout and add external pots if required from the connections below the trim pots...turn the trims to max (least or zero resistance) and the other external pots will work just the same...that means getting the trim pot parts as well. You may wish to think about switching as well as getting one later might mean a different order...generally a 4pdt switch is required but as I say, that does not guarantee that it can be installed into a complex wiring scheme or that you are successful in making this device...so beware getting too far ahead, over confident or hacking into the guitar before you are ready. MRJ sent me a file for the circuits so I may do some work on a stripboard version of the layout...but again, layouts without builds (although MRJ has done a bit on this) should be approached with a little caution...most of mine have some hidden fault that is only revealed upon building the thing. Perhaps someone more familiar with mouser and the circuit could check it out... pete EDIT: Hmm...what was I going to add? SMT is nice that they are giving away be be aware that they will be impossible to use...it will amaze you how small they get though, like a fly spec...for a complete power amp! I am not sure what you mean by clones...generally they are pretty similar although some say some are better than others marginally...this is a very old chip and some of the newer ones may even be a little "better" but really, it is such a standard chip now that many makers are doing them, JVC is a well known brand for instance...I am sure they will work. Edited January 4, 2009 by psw Link to comment Share on other sites More sharing options...
Donovan Posted January 5, 2009 Report Share Posted January 5, 2009 Yes, the links do not work, sorry. I could e-mail them. It is just a screenshot of an Excel sheet where the links do work, but I was not able to upload it into my post. Is there a way to attach it? The pots are for the 2nd scheme, but I am contemplating the 1st scheme as well and as you suggested, I am not going to rush anything,but it also makes sense that once working properly, I would prefer to only have the fundamental/harmonic mode switch located outboard. Further, I am not going to shoot for an internally mounted preamp/amp circuit as of yet. I want to get a functional outboard unit going, then slim the whole thing down using SMT components. I know what you mean about their size. As I mentioned in my first post, I have extensive experience building through hole and SMT assemblies. I am a subject matter expert in the electronics manufacturing process (certified trainer for all IPC manufacturing standards). If you are unfamiliar with the IPC, check out www.ipc.org. IPC spans all things electronics and is worldwide-recognized, but again, I am a mfg man, NOT design. For five years, I programmed and debugged high speed SMT lines for prototype runs of assemblies from all sectors of the market. I made it through the huge slew of layoffs after 09-11 and came up to New Hampshire from Massachusetts in 2005 after meeting my beautiful wife, only to end up at another electronics mfr, only this time it's solely electronic assemblies for interior/exterior aircraft power and lighting systems. I might be of service to you with your SMT-related endeavors. I do have some contacts that I might be able to coerce into laying out multilayered PCB that would allow a circuit with this low component count to be built amazkingly small. Their actual fab might be somewhat costly as as small production run, but I think interest here is enough to get others to chip in... I know I would. I also have a few resident nerds at my employer that I can probe on circuit-related matters. The LM386... by "clones", I meant copies my companies not familiar to me... example NJR (New Japan Radio Company). Did you ever come up with an op amp based pre-amp? I saw a few posts from about 6 months ago, but lost the trail. I stumbled across a chip I thought might be useful. Please take a look at the TL082 datasheet and tell me what you think. The statement within that caught my eye was... These devices are low cost, high speed, dual JFET input operational amplifiers with an internally trimmed input offset voltage (BI-FET II™ technology). They require low supply current yet maintain a large gain bandwidth product and fast slew rate. In addition, well matched high voltage JFET input devices provide very low input bias and offset currents. The TL082 is pin compatible with the standard LM1558 allowing designers to immediately upgrade the overall performance of existing LM1558 and most LM358 designs. These amplifiers may be used in applications such as high speed integrators, fast D/A converters, sample and hold circuits and many other circuits requiring low input offset voltage, low input bias current, high input impedance, high slew rate and wide bandwidth. The devices also exhibit low noise and offset voltage drift. Anyway I have one and was wondering if it might be something to try. I would need some guidance on the design side. Thanks again PSW and MRJ for your time and support. This thread is a huge body of information and its existence is very much appreciated. Link to comment Share on other sites More sharing options...
psw Posted January 5, 2009 Author Report Share Posted January 5, 2009 I think an opamp design is a good idea personally...but then I kind of moved on again in my designing for the circuit I now use as I wanted to include some basic AGC and decrease size and opamps didn't factor into this very much. For the oposite reasons to another thread on opamps in the general section here lately...super clean no distortion is ideal...we don't want the tone added distortions of the fetzer at all to run the driver. Remember ideally you don't want to haer anything of the sustainer circuit...just hte guitar sustaining...it is a different criteria... Still...opamps are generally different circuits and a little bigger once you add the viltage dividers and stuff to keep them happy. TL082 would be ok as anything from the TL071,2,4...061,2,4 (wjhich if i recall right is lower voltage or less power or something) and the TL081,2,4... But opamps are universal components and everyone makes them. The LM386 is similarly made by a heap of companies...NJC is very reputable and may even be "better" I forget...but all of them will do the job well enough. These circuits are severely limited by the available power...a 9 volt battery...and with that I am talking current...these things are poweramps...they will run down pretty quick compared to even an average analog stomp box or a preamp or certainly any conventional active circuitry in a guitar...battery accesss considerations are a must! My new circuit is pretty small...the problem with working with SMT (and there are a few in mine) is that it is no longer DIY and so the design and such needs to be top notch. My circuit is smaller than a 9volt and half as thick...5 times smaller than a sustainiac...but, there are 10 wires coming off it and a trim pot...any smaller and you are going to have trouble with soldering to the thing and connecting it all up....hehehe SMT stuff and the design and layout really is only good for some mass production and I don't think we are anywhere near that...I think I have maybe half a dozen interested in something from me that is proven to work...so you know...big thread...lot of years! Design things, even layout can be very tricky...unless you are building the thing. I can give a few pointers I guess...but I did have a little go at converting MRJ's circuit to stripboard and already I saw some more changes to make and then all of a sudden 2 hours has gone on a circuit I won't personally build...and then I will be asked to troubleshoot it and work out a parts order!!!!! Obviously I am very proud of this work and keen to encourage people, but on a persoanl level, it is time consuming and I am kind of moving on in some respects. Sitting over a hot iron making these things or pulling the rest of my hair out designing things and testing...has kind of lost it's appeal at least for now. The hope is that others will take it a little further perhaps... But...we will see...I may suddenly get more enthused and start making these coils and selling them too...money is getting tight! pete Link to comment Share on other sites More sharing options...
BRingoC Posted January 7, 2009 Report Share Posted January 7, 2009 Can someone help me figure out how to measure the impedance of the driver? I have an analog multimeter, which setting would I use and where would the test leads go? I am assuming on either of the two ends of the wire wrapped around the driver, but no setting on the MM seems to show me a corresponding impedance. The F/R works great, tested on a speaker, the driver and F/R both work "properly" to drive the strings, but the effect is not as intense as I was hoping for. I made substitutions, 30 gauge or the 25 wire not 20, I used a single coil tele neck pickup. The calculator website said about 180 turns to get 8 ohms, I believe I am in the ballpark on that (lost count a bit, oops) Also, the height of the area I wrapped around the bobbin is just about 1/3 the original size of the entire pickup bobbin, not exactly the 3mm. I've built a bunch of other pedals so this isn't over my head. Thanks a bunch. Link to comment Share on other sites More sharing options...
psw Posted January 7, 2009 Author Report Share Posted January 7, 2009 Well...I'm glad the circuit works...obviously have had some experience there...did you use the original posted circuit on the tutorial or did you add in my suggested modifications similar to MRJ recently posted? These extra caps really do help to stabilize the circuit against internal oscillations. This project has some significant differences to stompbox building and it looks like you broke the fundumental rule and will need to rebuild that driver. What is the rule... The secret to success in this project is in the specifications and quality of the driver! OK...so straight out you have not used the correct wire nor coil depth...this will not work! Also, winding calculators are crap...there you go! You are winding to 8 ohms, potting, glue potting is also important so expect it to get messy...see my pictorial linked in the sig below and do it just like that (but onto the pickup bobbin obviously. So...analoge is not the most accurate for this kind of measurement but it will do (they are great for some things though like detecting shorts)...you need to wind it and then scrape of a little enamel on the wire and measure from the start point to where ever you are up to (without breaking the wire) then wind some more...unlike a pickup and a lot of parts...you are not measuring 1,000's of ohms so you need to select the lowest scale to measure * ohms. If it is a little under or over (7.5-8.5) preferably a little under or right on is fine. Before rewinding with the correct wire, measure the resistance of the 8 ohm speaker you are testing the circuit with to give you an idea...also make sure that the meter has been reset to zero to get it accurate. As in the pictorial...preparation is the key...have the tape and meter and glue and everything all ready so that when it is all finished you can tape and clamp it up and set it aside to dry...otherwise it will loosen up. ... Still...you got the circuit going...compared to a lot of effects it is dead easy, but it is not where it is at in this project, nor is the F/R the idea circuit to drive the thing in my opinion...but it certainly has proved to do the job. There is no way around it...got to use the right wire and formula. I mean...you wouldn't go...ohhh, I couldn't find an LM386 or equivalent poweramp...so I stuck a 555 clock chip in there as it too has 8 legs and looks identical as any other 8DIL chip!...so why would you expect it to work with a completely different wire gauge...these things are very important and to understand why is to understand why this project works and other attempts fail...it is about frequency response, resonance and power to EMI ratios jsut for a start! Iknow...Iknow...but getting 0.2mm wire is such a hassle....what is 30 gauge anway...25-50% bigger or smaller...that's a significant difference don't you think? anyway...welcome to PG and the sustainer thread...looks like if you do it again correctly we will have this up and running in no time and people often need to have a couple of goes at the driver anyway so not much is lost...just take it off and wind again...and yes, it will fit in a 3mm space...and if it is a tele pickup...no it won't work under the metal cover! pete Link to comment Share on other sites More sharing options...
BRingoC Posted January 7, 2009 Report Share Posted January 7, 2009 Thanks for the lengthy reply. I have read through most of the forum, I would suggest that if there is a way to get the most current specs of how to build this thing tacked onto the end of the forum it would help. I had read in the forum that others had used the .25 wire, although now that I have used it I realize that I don't remember anyone saying it had actually worked out. I had gone to radio shack to get the wire, that's all they had and I didn't want to put in an order at mouser just yet, I'll have to now. The F/R circuit is built with the 100uf output, and the 10uf between pins 1 and 8, I omitted the 100k pots figuring that it would be running full up to get the strongest effect. I had run out of parts so I didn't add the 10k .1uf to ground part yet as I had thought it might not work right the first time and I needed other parts anyways. So, I did find out that the optimum/maximum effect was attained with the guitar volume at about 1/3 and the tone close to all the way off, this is a tele fyi, so I guess if I add the 100k pots and 10k .1uf to ground it would get the same result as the guitar pots. Also, this DID work with the metal cap on the pickup driver, although it was just a bit more subtle with it than without. Additionally I used an Elmer's wood glue, and as far as measuring impedance, I am confused still, wouldn't there be some impedance from the spool of still connected wire? And when measuring, I should touch the first end and then should I touch the actual wound coil, or the single strand end still running to the attached end? Thanks for the help, you have certainly done a lot of work on this. Link to comment Share on other sites More sharing options...
psw Posted January 8, 2009 Author Report Share Posted January 8, 2009 (edited) Hmmmm....I have repeated these things so often and many many pages have been discussed about this... The circuit should not be cut back on...things like the zobel network are vital (that's the 10ohm and cap on the output) but the other ones are there for a reason...sure it will work as a practice amp...but that is not what this thing is...nor is it an "effect" in that we are not signal processing. As for running the thing as hard as possible, somethings that can work...but generally you are going to need control...more power often results in more EMI (which is why it is not working properly...that and the faulty driver) so that you are using the tone control to short the highs that are driving the thing into oscillation and also killing the signal too...I ma not entirely endorsing MRJ's mods either...a trim pot on the in and out, a 10uF cap from pin seven and such are things I specified...as always people like to do their own thing...but then ask me. Honestly though...i know the thread is long and confusing...but I did do the pictorial and tutorial and answer all these questions as well as I can...I am not sure that I am often heard...so the posts get longer...hmmm...maybe I should say nothing. Anyway...don't mind me. Where were we... NO...you can not measure the wire first and then wind it...why would you want to anyway? There is a way of doing things...this is the way it is done...the resistance of the coil is going to cahnge as it is wound...I have even found that I have lost about 0.5 ohms sometimes between measuring the thing and cutting it (though there is no logical reason for this...you are measuring from the start to that point in the wire you are measuring too...the rest is of no consequence...the big changes are in not scraping the wire properly and get an incorrect reading, in experience with a multimeter or not zeroing it properly, that kind of thing). I also have a machine that winds a special coil I developed (the ultra thin coil) and have made so many as to know the count and a counter and a tension adjuster...however even here I need to measure a couple of times and that is really bad as I am working with epoxy! Machines are not good for the typical 3mm coil though, even I do those by hand faster, easier and with a better result. I am sure this was covered in the tutorial...but you will need to measure these things a few times...wind most of it then start measuring...as the coil gets bigger it will increase very rapidly. Also...never trust the calculators and other simulators for things like this. Well...with a tele if you have a tele bridge pickup (single coil lots of treble) we may need to tone things down a bit, maybe even up the output jack a little or filter the input...depends on the guitar. You may think it is working with the metal cap...and you could surprise me...but what is happening is a lot of eddy currents, lowering of efficiency and so you are using power you should be scaling back on and working the controls to filter the inputs and such...all very bad signs that your circuit is out of control...probably internally oscillating under load. Of course you wouldn't really hear this...as with a speaker the LM386 will seem happy enough...but we are not building a practice amp nor an effects box here. Also...I know I have said this many times...it is not just aimed at you... More power does not mean more sustain...it means more EMI...the whole project is a subtle balancing act and relies on efficiency to get a good result...it needs to run on the minimum power possible to produce the required effect...more is definitely not more ~ speed and efficiency is the name of the game! So...increased wire size (which I have been very very consistent about and repeated every few pages and why most people fail) will result in more electromagnetic radiation, but less driving power. Think of it like water through a hose...a thinnish hose can provide a good spout of water...run it through an 3 foot pipe and it will look like a dribble...you still get just as wet...but no spout. Put the same water through a very thin tube...and you just cant do it without a mega powerful pump of some kind to increase the pressure. I didn't just "make up" the 0.2mm wire cause I had it lying about or to be difficult...it came about by testing all manner of different gauges for this design...this is the wire that produces the result we are after. pete ps...i know my posts are long...but yours would be a lot easier to read if you could include paragraphs...I assume you aren't posting from a mobile phone there. Also...take some pics...I am sure this will work out ok and all I ask really is that people continue to contribute to help others...even mistakes. All these mistakes are things that have been done before and caused failure...those who have corrected them have generally been very successful. In know I sound like a know it all...but it is true...we have consistently had people think they know better (some may well...it is not hard in other things with me) but I know these things because I tried them...so when people think...using a squarewave to drive it and putting diodes in the pramp is a good idea for instance...they have found out that once removed...it in fact works better. People fall in love with ideas...I think I may have with my Hex designs...but there comes a time where the evidence is overwhelming Edited January 8, 2009 by psw Link to comment Share on other sites More sharing options...
mrjstudios Posted January 8, 2009 Report Share Posted January 8, 2009 Pete's right man. You HAVE to use the 32AWG .2mm wire. Early on, I like many others, thought 30AWG would be close enough (and to my defense, that was back before .2mm wire was definitively the standard ). It isn't 'close enough'. I did get 1 out of 4 30AWG wound drivers to work, but it sucked. So I finally listened to what Pete was saying about his extensive research and development, and sure enough, the 1st 32AWG / .2mm driver I made worked like a charm. I even used every other part of my existing setup -- the circut, the guitar, even the same driver as my 'best' 30AWG sustainer -- but I rewound it with 32AWG/.2mm, which also let me wind it to Pete's 3 x 3mm driver coil cross-section, and it was exponentially better. And this goes out to everyone: Clearly, Pete started this thread, and has the most experience with DIY sustainers. Also, he has done way more experimenting/developing/researching than I think anyone here realizes. How many hundreds of coils have you gone thru Pete? Maybe thousands!? So, I would highly recommend that the things he has posted as guidelines or rules should be followed. Then if you have problems, or you need help along the way, ask. That is what this thread is for, and I'm sure many here will be happy to help you. Ideas and innovations are always welcome too, but if for example, you decide to build a F/R based sustainer, and a driver based on Pete's design, then please do not take shortcuts and expect it all to work. Most of the 'innovating' done by people here (myself included) is merely trying to get by with spare parts on hand, or taking shortcuts because "that part doesn't matter that much," etc. etc. You wouldn't set out to build a car (a highly researched and developed existing design) and then try to 'get by' with square wheels! So anyway everybody, listen to and appreciate the wealth of info that is Pete, and do your homework! Link to comment Share on other sites More sharing options...
Hank McSpank Posted January 11, 2009 Report Share Posted January 11, 2009 (edited) Obviously, by arriving here...I'm interested in a Sustainer type device, but with a slight different mod. I would like the sustainer to fade in a harmonic, when a foot switch is pressed - yes, I know this would need some wiring from the footswitch to the guitar onboard circuit, but I'm toying with the idea of a ring tip sleeve & using a stomp box to have the 'switch' (using the spare 'ring' to ground as the activation for the harmonic to kick in). ANy thoughts...comments? Also does anyone have any comments about possibly reversing the function of hex piezo bridge saddles to make them excite the strings thereby yielding a form of sustain? Edited January 11, 2009 by Hank McSpank Link to comment Share on other sites More sharing options...
psw Posted January 11, 2009 Author Report Share Posted January 11, 2009 Welcome Hank McSpank Must run out...so come back later... for now...have a look a the tutorials linked in my sig below...shorter than 282 pages...but quite a bit of learnins will be required... Also does anyone have any comments about possibly reversing the function of hex piezo bridge saddles to make them excite the strings thereby yielding a form of sustain? This one is easy though...it's not going to happen... foot switches are always a problem...more on this later...but why a foot switch and not just a swithc or pull pot on the guitar? As in recent posts...the secrets are in the driver...there are latest circuit versions of the previous page I think...and there are limits to the technology that really do need to be appreciated. This is not a signal processor like an effects box...this is a fundamental alteration to the guitar and it's wiring. While external devices have been proposed, the problems are virtually insurmountable and the advantages, if there are any...are difficult to see if looked at objectively... maybe you could convince us further on your proposal...but as I say...got to run for now...different time zone...infact...it's monday morning here! pete Link to comment Share on other sites More sharing options...
mrjstudios Posted January 12, 2009 Report Share Posted January 12, 2009 (edited) Obviously, by arriving here...I'm interested in a Sustainer type device, but with a slight different mod. I would like the sustainer to fade in a harmonic, when a foot switch is pressed - yes, I know this would need some wiring from the footswitch to the guitar onboard circuit, but I'm toying with the idea of a ring tip sleeve & using a stomp box to have the 'switch' (using the spare 'ring' to ground as the activation for the harmonic to kick in). ANy thoughts...comments? Welcome. This type of thing could be designed, but think of all the interference you will accumulate along the way to and from a pedal. As PSW has said, that would be extremely hard to overcome. Perhaps impossible using the current technology. Maybe try to accomplish this instead/first: design a 'blend knob' into the circuit so you could fade between the harmonic and fundamental modes, and have this knob right on the guitar. This, I think would be possible, and if I remember right, has been done before. I can't remember who incorporated this into their design though, and if it was ever fully proven working. Also, have you built a working sustainer in general yet? If not, I'd recommend getting one up and fully working, and then try to add in whatever else you are interested in. Edited January 12, 2009 by mrjstudios Link to comment Share on other sites More sharing options...
psw Posted January 12, 2009 Author Report Share Posted January 12, 2009 Well...that was a wasted trip...hmmm...so I am back... Piezos...certainly conventional saddle piezos can never generate the kind of forces necessary, especially located at the end of the string without leverage required to produce the effect. I notice you also resurfaced the 4 mod tutorial in the general section...this is immensely misleading and no one has actually got it to produce anything but microphonic feedback...this is not sustain and certainly not a sustainer! There are lots of things that could be done once a person has got the know how and will to continue with the project...but as MRJ was suggesting...not until you have made successfully a basic sustainer similar to the way I have outlined and used that as a starting off point...and you can deal with failure, as there will be many failures... Speaking of which...perhaps not thousands, but certainly hundreds of coils and general experiments have been made by me at least, and a fair few by others to verify my results...in developing a formula and basic principles for a working sustain device. A lot of what I haven't really discussed were ideas and research into potential uses of piezos and other approaches including the "acoustic" sustainer model C, shake the whole neck by the headstock and variations approach. The idea of a harmonic footswitch though is a little off the wall...both practically and technically. Part of it is that you need to come to terms with some of the forces and signals at work here and how they interplay. With a sustainer you are running a fair bit of power through the coil...the leads running from the coil are, if you think about it...simply an extension of the coil and putting out similar EMI qualities as well as the length of this extension affecting the impedances and wasting a substantial amount of energy...as stated above...efficicency is a key requirement, additional power will not compensate for this, it will only make it worse. So...if you were to run the driver leads all the way up and down the signal cable to a foot switch rather than a short lead to a harmonic switch...you are going to create an incredible amount of problems. An alternative would be to have a signal phase switch to create the harmonic effect...but there again, there are practical problems that one have to wonder why a simple phase switch on the guitar wouldn't be so much more practical. Also...you ar not looking at one additional wire in the guitar lead (like a stereo cable) but dual sends and returns at the very least...plus the guitar signal...plus a fair amount of shielding...so we are talking about a decent multicore...not something I'd want hanging out of the guitar, nor cheap...if it worked, which i doubt!!!! Another thing to note is that it is possible in addition to the fundamental drive, and the harmonic drive...to have a mixed drive. My circuit suggestions with the 100uF cap is a kind of comprimise to give decent performance on high and low strings and harmonics...but in normal mode, the lower strings tend to "bloom" from fundamental to harmonic pitches in a very natural way. Upping the cap may provide a more true low string response...but lose a lot of high string response and harmonics. With a guitar like a tele though, maybe it needs a little more bass response and something like a 220uF might be worth a shot...different guitars may need tweaking. One avenue to explore may well be an adjustable filter, and this has been spoken of, that allows a variable treble bias for the sustainer circuit. A more practical approach for working the harmonics of the sustainer is to use a standard wha to vary the response of the signal...I find that a wha can completely cut the high frequencies of a sustainer in harmonic mode or bring them out so that they scream...so a variable pedal effect right there. Particularly effective with distortion as well. anyway...a few small observations...thanks MRJ for chipping in there... pete Link to comment Share on other sites More sharing options...
Hank McSpank Posted January 12, 2009 Report Share Posted January 12, 2009 (edited) Ok, thanks for the replies. Re the circuit - I see one in your tutorials...but I can't see where the harmonic switch fits into the equation? (the circuit I'm referencing is the one lifted from a small amp design driving a speaker - is there an updated one showing where the harmonic switch fits in). Without referencing this it's difficult to reply to your specific points, except I was thinking my proposed the footswitch wouldn't need to be in the actual overall signal path & could merely be used to activate a solid state relay, whose contacts in turn enable the extra circuitry needed for the harmonics) Re the piezos...point taken (& concur, as I had considered that there might be a problem generating enough energy at the bridge!!) Edited January 12, 2009 by Hank McSpank Link to comment Share on other sites More sharing options...
psw Posted January 12, 2009 Author Report Share Posted January 12, 2009 Hmmm...Well Hank...this is going to take some reading on your part and a lot more depth of understanding if you are to be successful...that does not mean reading the whole sustainer thread (that might confuse you more) but you do have to do a little more I suspect than you have so far. A good thing to do is to read the last few pages to see where things are at and get a feel for the conversation...it might answer some of your questions. Lets see... I thought I had mentioned MRJ's circuit on the previous page...but perhaps not...so here it is again...two pages back now. However...i would still make other alterations which I had listed previously...but time and motivation to do another version is against me on this...it is also slightly untested, but it looks ok to me. Also...I know the switches are listed in the tutorial...but that one isn't "mine" (as in I didn't start it) and so has some problems...however, I added to that later on and I put my diagrams in there. MRJ's way of wiring the switch is unusual as mentioned back a page or so..it fooled me, but seems to ok... Basically...it is a phase switch on the driver leads, reversing them. However...you have failed to explain why you would want this function in a foot switch. You now mention a relay...not a good idea in a guitar...you are likely to create noise and adding more coils into a guitar and possible switching EMI is rarely a good idea. The control voltage is effectively AC so it tends to transfer into the nearby signal all the way along the guitar lead. It is not going to be cheap either...and I honestly don't understand why you would want to do this...can you explain a little? Also...I thought you were proposing something that faded into a harmonic... I would like the sustainer to fade in a harmonic, when a foot switch is pressed hence my explanation into various new areas to explore that might further achieve that in addition to the phase switch method. The idea of using a footswitch hints of some misunderstanding of what the sustainer does perhaps...so please explain more so I can do the same. You need not know how it works to explain why on earth you'd want to do this kind of thing over a simple switch or push pull pot on the guitar itself! Anyway...have a good look and read of these things...this is not a circuit based project...take particular note of the coil winding pictorial...yes you need to get the circuit right...but the secret is in the driver and the balancing of the forces...more power does not help things or compensate for lack of efficiency...see recent pages for more of that kind of thing and read back a little ways to see where people have failed or succeeded in the project... pete Link to comment Share on other sites More sharing options...
Hank McSpank Posted January 12, 2009 Report Share Posted January 12, 2009 (edited) Again...tks for taking the time to reply. I should set out my stall...I was trained in electronics in the British RAF (not in design, but repair)...so none of the sustainer concepts are hard to grasp (or circuits to read) You might think I'm being lazy, but it seems crazy that you've done **so** much fantastic work, that anyone new here still has to set off on an unecessary journey. Unless I'm missing some obvious posts...none of the links in the foot of your sig actually has a link to the latest variant of the circuit used? (sorry if that comes across a bit blunt...it's not meant to - a circuit speaks a thousand words & a 282 page thread is just too much to contemplate!). Maybe I've jyust got to start heading back from page 282 to find the 'end schematic'? What you've posted in your last post is more a board layout...sure, it's such a simple circuit I can almost visualize the circuit in my head from it...but it would have been nice to see the actual circuit diagram...mainly to see how the harmonics switch fits into the overall circuit *including your driver*. You say the harmonics switch is just changing the phase, but that'd still nice to see in circuit format (looking at the board layout wiring, it would appear to be a 180 degree phase reversal...my initial reaction is that this seems a little puzzling ......as I'd thought that'd just kill off the vibrating string pretty darned quick?) Re the footswitch...well my reasoning is that guitarists often have their hands tied up...I thought it'd be cool to have a 'momentary make' footswitch to bring in the harmonics on the fly (I'm aware that probably in a long sustain playing mode a guitarist's right hand is propably free to do any onboard switching)...but also sometimes it's just cool to have the bare minimum of switches on the guitar itself! By using a footswitch it rids you of one at least! (I'd be doing this for a studio guitar...not a live guitar, so it doesn't matter too much to me about onboard switches on the guitar...in fact less is more in my case - the less drilling on my guitar the better! I'd also toyed with the idea of a longer fade in harmonics option (user adjustable)...I may be wrong but sustainers I've seen to date tend to have a very quick impact once the harmonics switch is flicked. Therefore I thought it might be nice to have that aforementioned footswitch that once pressed the harmonics fade in over a user preset time(approximate time!). But hey...you've done *amazing* work here - I don't want to come across as some new poster turning up trying pick holes in all your good work! Edited January 12, 2009 by Hank McSpank Link to comment Share on other sites More sharing options...
psw Posted January 12, 2009 Author Report Share Posted January 12, 2009 No...that's ok... But...be aware that most of this thread is about answering very similar questions...so it grew well out of proportion. Also, it is a work in progress...there is still work to be done. The circuit is contentious...I don't like the Fetzer Ruby solution and have never made one...so I don't like to say "endorse it"...nor did I write the original tutorial where the fetzer ruby first appeared. Personally I have my own circuit...but I have no formal electronics background and don't have an easy way (other than pen and paper) to write out circuits...so if this is you volunteering to do that, that would be cool...but so far many, many people have made this thing and not contributed anything like that even though I am sure some could have...oh well...maybe you would give it a go. Basically...my design allows for a very basic but stable amplifier circuit to run it...the cleaner the better...some AGC control, preferably forward feed may be advantageous...for more harmonic control some kind of Q filter may be the way to go...and the preamp or buffer is essential to prevent loading. It can use any simple circuit like this because of the driver design and specifications...simple I know, but critical as people so often find out to their detriment. The commercial units take a different approach....they use a fair bit of phase compensation circuitry for instance to overcome the driver inefficiencies. Yes...it has often been debated about the confusing...too many cooks, too many variations, no clear do this plug and play tutorial...but this was initially a thread about ideas like you have put forward...variations and such "sustainer ideas" as the thread says. However...as the only one left from the beginning...a lot falls upon me and I have moved on a little. I now have my own circuit design, you might develop your own...MRJ is trying to "fix" the problems with the fetzer ruby...col made a far more elaborate circuit that may better suit your tastes for tweaking. As for modding your guitar...this thing does require substantial rewiring and such...replacement or modding of the neck pickup or building in of a driver, easy access to a battery...this is not a low mod kind of thing...my tele is about as low mod as it might get I suspect as far as design goes...the very least of your problems is the harmonic switch and adding relays into the guitar is going to be more of a problem over the installation of a push pull pot say. Anyway...DIY allows you to play with these ideas...I would suggest making a basic circuit and driver first and give it a go in test mode without modding the guitar at all and work from there. Frustrating I know...but it is the way things evolved and the character of the thread...it would also ask someone...well, lets face it ME...for no real reason to do a lot of work for absolutely no reward. Too often the DIY sustainer project becomes pete does it for me sustainer project...sorry no can do! pete Link to comment Share on other sites More sharing options...
Hank McSpank Posted January 12, 2009 Report Share Posted January 12, 2009 (edited) No...that's ok... But...be aware that most of this thread is about answering very similar questions...so it grew well out of proportion. Also, it is a work in progress...there is still work to be done. The circuit is contentious...I don't like the Fetzer Ruby solution and have never made one...so I don't like to say "endorse it"...nor did I write the original tutorial where the fetzer ruby first appeared. Personally I have my own circuit...but I have no formal electronics background and don't have an easy way (other than pen and paper) to write out circuits...so if this is you volunteering to do that, that would be cool...but so far many, many people have made this thing and not contributed anything like that even though I am sure some could have...oh well...maybe you would give it a go. Basically...my design allows for a very basic but stable amplifier circuit to run it...the cleaner the better...some AGC control, preferably forward feed may be advantageous...for more harmonic control some kind of Q filter may be the way to go...and the preamp or buffer is essential to prevent loading. It can use any simple circuit like this because of the driver design and specifications...simple I know, but critical as people so often find out to their detriment. The commercial units take a different approach....they use a fair bit of phase compensation circuitry for instance to overcome the driver inefficiencies. Yes...it has often been debated about the confusing...too many cooks, too many variations, no clear do this plug and play tutorial...but this was initially a thread about ideas like you have put forward...variations and such "sustainer ideas" as the thread says. However...as the only one left from the beginning...a lot falls upon me and I have moved on a little. I now have my own circuit design, you might develop your own...MRJ is trying to "fix" the problems with the fetzer ruby...col made a far more elaborate circuit that may better suit your tastes for tweaking. As for modding your guitar...this thing does require substantial rewiring and such...replacement or modding of the neck pickup or building in of a driver, easy access to a battery...this is not a low mod kind of thing...my tele is about as low mod as it might get I suspect as far as design goes...the very least of your problems is the harmonic switch and adding relays into the guitar is going to be more of a problem over the installation of a push pull pot say. Anyway...DIY allows you to play with these ideas...I would suggest making a basic circuit and driver first and give it a go in test mode without modding the guitar at all and work from there. Frustrating I know...but it is the way things evolved and the character of the thread...it would also ask someone...well, lets face it ME...for no real reason to do a lot of work for absolutely no reward. Too often the DIY sustainer project becomes pete does it for me sustainer project...sorry no can do! pete I'm certainly not after everyone to do it for me, but it would seem stupid to reinvent the wheel...hence my question about a circuit diagram ....it's surprising that the thread has got as long as it has without a couple of circuit diagram variants attached? I guess I'm just going to have to have a monster session wading through it after all! Off topic - I've recently just finished off designing my own onboard circuit which blends piezos & magnetic pickups & also drive a midi guitar unit (from an old Variax body http://uk.youtube.com/watch?v=mBYPqqGdcKg ) so I'm certainly up for a challenge! Edited January 13, 2009 by Hank McSpank Link to comment Share on other sites More sharing options...
mrjstudios Posted January 13, 2009 Report Share Posted January 13, 2009 I'm certainly not after everyone to do it for me, but it would seem stupid to reinvent the wheel...hence my question about a circuit diagram ....it's surprising that the thread has got as long as it has without a couple of circuit diagram variants attached? I guess I'm just going to have to have a monster session wading through it after all! Off topic - I've recently just finished off designing my own onboard circuit which blends piezos & magnetic pickups & also drive a midi guitar unit (from an old Variax body http://uk.youtube.com/watch?v=mBYPqqGdcKg ) so I'm certainly up for a challenge! If you'd like, I could draw up a traditional schematic for my layout shown above. The reason no schematic was ever drawn up here is because most people either can't read them, or would rather just see it all layed out already. It is one thing to design a schematic, and another to organize it and lay it out in 3D on a board! So, I think for simplicity, and because the DIY Layout software is so darn handy, most circuit designs are immediately put into layout form by their authors. But I think it is a good idea to have at least 1 schematic floating around. Maybe it would encourage people to make a more compact or better functioning layout. Gimme a day or so and I'll draw up a schematic WITH driver and harmonics/fundamental switch included. Link to comment Share on other sites More sharing options...
psw Posted January 13, 2009 Author Report Share Posted January 13, 2009 It can use any simple circuit like this because of the driver design and specifications...simple I know, but critical as people so often find out to their detriment. The commercial units take a different approach....they use a fair bit of phase compensation circuitry for instance to overcome the driver inefficiencies. So...from the above information you should have more than enough of an idea what is required...a number of circuits such as the fetzer ruby may as well meet the purpose. As for the driver...my design is specific...0.2mm wire wound to approximately 8 ohms in a thin coil of around 3mm generally as close as possible to the strings glue potted while winding. I am sorry if you feel let down in the information and the assistance given here...I don't after all get any financial or other benefit from providing this information...so I guess you got what you paid for. There are plenty of circuit diagrams and heaps of other information provided within the thread, many variants over the years...quite decent ones on the page previous to your first post...enough information in my last post to design your own! On the other hand, the thread is as long and convoluted as it is because I feel compelled to try and help people and give them a start with the benefit of my successes and failures (as much as anything)...if not for that, perhaps it would be more concise and prescriptive...but the thread is about "sustainer ideas" not a thread detail the specifics of how it is done, as there are many ways. There have been many who have contributed to it over the years in this format and clearly quite a few who appreciate it's intention as a forum to explore these things with like minded souls. As it is the only known depository of information regarding such a project on the net...I am afraid you will either have to persevere with us or indeed perhaps reinvent the wheel and post your own results, pictures and diagrams...then five years later, you can get as surly as I have become! pete Link to comment Share on other sites More sharing options...
Hank McSpank Posted January 13, 2009 Report Share Posted January 13, 2009 (edited) Duplicate post (can't find a delete post button!) Edited January 13, 2009 by Hank McSpank Link to comment Share on other sites More sharing options...
Hank McSpank Posted January 13, 2009 Report Share Posted January 13, 2009 (edited) I am sorry if you feel let down in the information and the assistance given here...I don't after all get any financial or other benefit from providing this information...so I guess you got what you paid for. pete I don't feel let down at all ...it just a little puzzling not to have a circuit diagram posted up for a device that uses an electronic circuit to drive it! (& whether I'd paid or not, I would have felt a little cheated to have waded through 282 pages & not see one!) Surely one of the purposes of the thread is to evolve a good basic sustainer design (from which folks could then set off on a journey/variant of their own) but for anyone to do this, they'd need to see the basic existing circuit?! But I think it is a good idea to have at least 1 schematic floating around. Maybe it would encourage people to make a more compact or better functioning layout. Gimme a day or so and I'll draw up a schematic WITH driver and harmonics/fundamental switch included. Most excellent - I look forward to seeing it. (even a photographed hand drawn sketch would be great) Edited January 13, 2009 by Hank McSpank Link to comment Share on other sites More sharing options...
psw Posted January 13, 2009 Author Report Share Posted January 13, 2009 Well...The F/R with my suggested mods and stuff is only 16 simple components...this circuit hasn't even been fully verified by building and testing in this layout...but I guess someone with time and motivation and the know how could write out the diagram. Although...anytime schematics have been posted linked or suggested..the next question is invariably, where's the layout! In fact the F/R solution has always been controversial and effectively killed development when someone came along, ripped off ROG circuit, who ripped it from data sheets and elsewhere, and posted it in a tutorial without even successfully ever building the thing really, in a rash of enthusiasm. Ever since, people have picked up on it and used this as a basic circuit and with a few exceptions, killed of real development. Col and stribs circuits being notable exceptions. Yet there were always problems with the ROG versions as has been suggested and I made suggestions to which MRJ has kindly done a layout generally of. But still the F/R has persisted. Here is your chance to shine...take this little layout and make a schematic for yourself...it is only tiny really...then you can do a layout for it...so we are back to where we are at almost...then you can build and test it...so we can then say that there are no faults in the scem or layout...and then we can post it up with some authority. But honestly...all we have there is another F/R...hmmm But...you could take the Sustainer Ideas thread for what it is, make a proposal, engage in some research and discussion...have a good sit down and design something, get a layout worked up...and then you can build it test it and modify it...and then you can have all that you desire. That's what I do...you can too. I am sorry for being cranky...difficult times...but this is a DIY thread...and while I do attempt to have a discussion about things and have my own ideas and thoughts about things...this only exists because I and a few fellow travelers decided to take a different approach to the sustainer thing. Now...if you'd like to take a more conventional and possibly superior route...look up the obvious patents (some are on page 7) and you will find a whole heap of schematics to look at, some spanning several pages...and not a few different driver approaches too. We have also discussed things that I have done or created and that sometimes the published technology is behind the work that I have done. I have never liked nor used the F/R but have always adapted circuits or designed my own solutions. Contentious and frustrating as it may seem to others, some things remain mine...like the Hex designs or the design and components of my own circuit. I have given more than enough information for people to develop their own...but at this time I don't see any reason to give these things away. Most people would and do find a layout (preferably verified) far more useful...people who have a good schematic reading capacity and ability to derive a layout from it, wouldn't need a schematic. I can only speculate as to why you need it really or can't bring yourself to do it yourself! There have been a few people who see all this and think...hmmm...if i had the schematic, i could give it to my mates who could shrink it down and sell it back. However...the ROG thing has some copyrights to it, and so does some of my work...and really...all you would have is a bad circuit shrunken down and further killing off development for something better. And, perpetuate a myth over the circuit being anything really special to the success of this project when in fact it is the driver alone that allows such simple circuits to be used. Yes...I think it might be a good idea to go back and skim through the thread...or at least go back a few pages...the MRJ circuit was on the previous page for instance had you flicked over... But you know...I am feeling so cranky...I honestly feel like suggesting you plug back into google and do the search again and see if you can find anything else on this subject and follow that course. Google got you here, but reading and doing is what gets results...time to get busy...and perhaps draw that schematic yourself from the decently clear layout there and or the various data sheets and other links and DIY...which is the general idea. pete Link to comment Share on other sites More sharing options...
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