mrjstudios

I wish you the best Pete, and I hope you can continue to contribute to the thread in the future! And enjoy your new location!

Well, I've still been looking in and reading up on the thread every now and then.... I haven't deserted Col: I think the work you are doing is very solid. In a completely coincidental and unrelated way, I seem to have experimented and confirmed some of your results earlier on. I was working towards a much simpler and different purpose at the time, but the things you are discovering about wire thicknesses and also the overall impedence of the coil make lots of since to me now by dumb luck! My first successful driver was a .25mm/30AWG driver wound to about 5-6 ohms, driven by a 386, and the only driver I ever had that topped it was one I made much later based off of PSW's driver concept. Had I been able to make that first driver to the same quality as I made the much later PSW design driver, who knows how well it could have worked, although it shouldn't work that well logically. I also had a more radical 4 ohm driver (dual coil) at one point that seemed to kinda work well in some facets, but I think the fact that I was still using a 386 to drive it was the problem. At the time, I dismissed its problems as poor driver design, but with your great new discoveries now I'm wondering if that was really it.... at that time I understood significantly less about circuits, and so I probably overlooked some of the power stage's problems with driving about 3.85 ohms. Anyway, great work.

Col: Ha, I doubt I know more than you do! But I do think I am starting to understand the design of your circuit a lot better. I'll have more of a look at those links soon, and I may well try to build one. I think I'll test it with a 'thin driver' design though for now. I did make some dual coil humbucker-like drivers back when everyone was doing that, and I did get 1 working, but I am a bit more confident in my single coils at the moment. Eventually, I'd like to have a sustainer in a regular humbucker-sized pickup format...

Hey Col and PSW, I'm all for a newer 'standard' DIY circuit, that will put the Fetzer/Ruby like designs to rest! The only reason I have kept it alive, is because I know I have had good BASIC results with it, as well as many others, and for those of us who can't just whip up a circuit design from scratch in a day or two, there still isn't much out there to go on. I'm not blaming anyone here -- it's just a fact. (Most of the stuff here circuit wise is either not working, or super advanced for the average DIY'er.) That is why I was hoping to revamp the F/R and finally have an easily accessable circuit that people know they can build, and upon correct completion, get basic results from. If you can lend your circuit genius to making a better 'standard' then I'd be happy to help, test, develop, design, etc. Also, my area of specialty is really with tube amps, and since the Fetzer valve is designed to operate relatively like an old fender input stage, I perhaps understand it better than op-amp stuff . But I'm learning more and more every day about op-amp and other IC chip designs, and this forum helps a lot. Col, could you re-post your advanced circuit that you had so much sucess with? I'd be happy to build it and 'verify' your results -- and hopefully learn more about the design behind it in the process, and thus learn more about the theory that goes into this type of solid state sustainer circuit design.

It is a PVA driver, wound to your .2mm wire, 3mm cross section specs. It is wound around an old single coil pickup which has had it's bobbin blocked up leaving the 3mm at the top. I'm gonna test everything, but I'm about 95% sure it is the driver. There is a definite point at which I can crank the circuit up to before it goes from driver winding oscillation to circuit screaming. Actually, the trim pot on the LM386 works pretty well. I was able to run at almost full gain there, and full gain coming from my preamp before the circuit went nuts, so it is MUCH more stable than a F/R. I think what happened is that this particular driver isn't super tight. I vaguely remember when I made it that my clamps holding the sides in while it dried weren't super good... but I figured it would be fine with all of the PVA glue potting it. And it did work for a while, but I think after it took a fall, and the leads got twisted and pulled a bit, the very inner windings must have let loose. So there must have been a slight air gap in the potting... I hate it when that happens. It isn't grounded to the core either... the plasic pickup bobbin is still intact and protecting from that. The windings may be shorted though... Oh well, back to square one. I know I can reuse the driver itself -- I'll just need to rewind it. And I'll test the circuit with a little speaker to hear how clear I can get the ever dismissed Fetzer type valve

Hope you are doing ok Pete!... Well I finished installing my new circuit in my sustainer test guitar. Circuit: works great. (as far as I can tell -- I'll hook it up to a speaker to see just how clean it is). I had none of the biasing problems people have had in the past with the F/R type circuits. In fact, it took me about 3 seconds to have the thing right at 4.56 volts (perfect), where in the past I had to fight with it to get it anywhere near the 'clean' operating range, and even had to carefully select batteries. Also, everything was much easier to wire up and get to with the new layout. SO... the new design and my layout is definitely a step up from the stock F/R. Driver: at some point the driver got banged around a little bit, and it seems to have let loose and now the internal windings are vibrating I did have working sustain with this driver in the past, without any huge problems (the problems were in the circuit), but now something has gone awry internally, and it is oscillating so bad you can hear pitches coming from the driver itself (not good at all). So with this major setback, I'll either have to resurect my trusty first driver, which I was lucky enought to have work well the first time, or I'll have to rewind my current strat pickup turned driver. (Note: the first driver is the blade design which can be seen on my youtube video from so long ago)

Very cool clip Pete! Always good to hear these things in action. On a similar front, I have just finished building a new sustainer circuit from scratch (the schematic I posted a little while ago). I used the new layout that I designed too, which can also be found a few pages back. It's just a matter of getting 1 more capacitor and installing it into my already sustainer equiped guitar to finish it. My drivers are largely, if not totally based on Pete's designs, and have been heavily influenced by his guidence along the way as I have built them. So if the new circuit design proves functional, (which I think someone has already verified), then I will be able to contribute another test subject proving the thin driver design's concept. Once the thing works, I will also be able to record as many demo's as desired and some video as well. No, you won't learn anything new from them if you have read the thread, and you won't finally 'see the magical components' (because they don't exist)... BUT sometimes it helps people to hear and see things, rather than just read about them. Also, I'd like to get plenty of samples up just for the sheer purpose of having an audio and visual record of what great things have been accomplished here. I know not everyone has a recording studio or even a decent video camera, so I hope I can be of service in that aspect. Hopefully others will be sucessful with their builds as well, and also post videos and audio, making a kind of reference database of what can be done using for example "PSW's the thin driver design, and a 386 based circuit", etc. etc.

Uh oh! Did I hear the word "MDF"? I'm glad you have finally given in and found the real tone wood Pete haha. (Note to everyone: do not try to build an MDF guitar )

If you look at the 2nd drawing I posted, I moved C2 (and I think it is called C5 in the second one) right next to the IC chip. Like I said before, there were things about the original F/R layout I didn't like.... The from scratch circuit I am working on will be the 2nd (new version) drawing that I posted.

Which capacitor are you refering to? Is it in the part of the circuit that is like the one 1 posted, or is it in your new preamp? I've just gotten the rest of the parts today that I need to build a from-scratch version of my circuit layout (found a few pages back). I know the older F/R-like layout works, but there are things I don't like about it so I'll compare the two, and see if my new layout fixes the problems. I'm also re-wiring the guitar again from the ground up, so hopefully this latest attempt will produce a (consistently) working sustainer. If it does, I'll definitely post some demo sound clips and videos too. I'm going to work on the new unit over the weekend, so we'll see how far I get...

I have also had this noise problem with my sustainer circuits. Do you only get it when you turn the thing up to a certain point? Mine always would start in buzzing rather quickly, and as you went up in power, the buzz frequency would change a bit and sort of 'sweep' across a range of notes, and then settle on 1 nasty hum, regardless of adding any more power. I would describe the final hum as sounding like a 60 cycle hum, or the car engine/amp analogy. It IS NOT the 386 itself, since I have had plenty of perfectly working 386 circuits... but, it seems to be a recurring problem at least with F/R based circuits. I actually spent a lot of time recently on my previous 2 circuit attempts (I should add, these circuits were NOT the new schematics I have posted -- they were differently and less modded F/R's) trying to rid them of this buzz... hmmm... some troubleshooting: Keep in mind my test guitar has only a bridge humbucker, and a single 500K volume control, so I doubt this buzz is caused by other pickups or guitar switching/electronics. (Note: As Pete and others have discovered and have said numerous times, other pickups in your guitar can and will cause problems if not dealt with correctly... but in this case, I am ignoring that set of problems for troubleshooting purposes, since I have eliminated them from my setup.) The buzz I experienced was totally uneffected by outside forces such as EM radiation, computers, tvs, lights, etc. No matter where the guitar was, it buzzed the same. So if it is a grounding/power supply issue with the F/R type circuit, it must be internal with the interfaced guitar and sustainer circuits, and not an external shielding issue. The buzz like I had, and you seemed to describe, is definitely NOT a result of driver/pickup feedback and interference. That is more of a squeel and is effected by driver position, etc -- this buzz is not (trust me, I tried moving it all over the place...) Soo.... that kinda leaves 2 things. Slightly bad driver (and I say slightly bad because even a driver that internally vibrates and has flaws CAN work to an extent, although never well), bad circuit. The circuit could be anything from design, to bad layout arrangement, to bad solder joints, etc. Maybe check where your input voltage is running carefully... good luck man!

Donovan: Great job in drawing up a new circuit. I had considered a TLA082 based preamp in one of my designs, but with it running into the good old 386 circuit you can see in the latest layout I posted. I ultimately didn't ever finish the design, because the more I read about the TLA082, the more it sounded like it would distort just about as much as a J201 or similar JFET. But there was a few things that did seem to be promising about the TLA082. Some of the driving problems you have sound like overpowering the driver (take it from me, I have tried that and as much as you want more power to = more sustain, it doesnt.) Any reason why you can't use your preamp running into a 386? I beleive that with a good driver, the 386 power stage has more than enough power and it is a familiar and easily manipulated power amp. Also, they are very easy to get about anywhere around the world. I think maybe some of the odd problems you are experiencing could be caused by the fact that your new power chip has extra features in it... but I can't be sure. It might be worth trying to run your new preamp into a 386 power section and see if that solves some of the problems.

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.

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.

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!