mrjstudios

To be clear -- I am building a mid driver type design, but it is going to be used in this guitar. *Body Design Copyright 2007, MRJ Studios* So, yes, I am building it to funtion like a mid driver - but it is not going to have a neck pickup above it. It does need to be as stable and quiet, however, as a mid driver because of its very close proximity to the single coil (for now, HB later) pickup. -MRJ STUDIOS

My single coil looks like this -- It seems to be much easier to use a separate magnet and core. I used a 3mm thick steel piece as the core and then magnetized it by glueing a magnet to the bottom of it. It works pretty well. You can see it being tested at http://www.youtube.com/profile?user=MRJSTUDIOS -- just click on the sustainer video. -MRJ STUDIOS

Well, the shielding aspect shouldn't be important (remember what you told me, heh he he). But like I was going to do before, make the shield section independent of the mounting structure, and then test the sustainer with it off. You could then add it later very easily and see if it kills efficiency or does anything at all. I'm still not sure about that Aluminum strip that you used to bridge the gap between the cores though. Since the cores are being magnetized by the driver working, then they must have an electrical current induced in them. And since Al is conductive, it will happily carry that current back and forth, which will create another magnetic field. Who knows if that whole process will make anything significant electrically or magnetically, but to me, it's kinda like wearing metal boots when working in a power plant.... I just hope I can get my coils closer in ohmage than yours turned out to be -- not sure how I'll ensure my success yet though. CREP For the sustainer amp you need to: tap into the output of your pickup signal send that signal into the input of your F/R amp (that is what I use, it is a good one) Ground everything to the battery (-) AND to the guitar ground send the outputs of the F/R to the sustainer driver (instead of a speaker, but same principal) For the sustainer Driver you need to: read over this forum, and pick a proven design (these new dual core ones are in development; a single coil sustainer is easier to build and proven to work) The basic structure is: A pickup type magnet attached to the bottom of a steel (magnetic) core some sort of magnet wire (from .18mm - .25mm) wrapped to 8ohms around the core as tightly as possible some type of bobbin to hold the coil together the coil is doused in PVA (elmers) glue to solidify it and 'pot' it Before you start building, read as much as you can on the previous pages about the single coil designs and the F/R amp.

Nice work as usual. The core looks as small as it was supposed to be. Still no wire here.....

Dont worry. In fact, I would love to be keeping up the pace with you but like I said, no wire. I can't wait for this wire to come... I think I'll route the sustainer guitar (#XS002, pictures shown before) today or tomorrow, so it will be ready to take the new system when it gets done. By the way PSW, Avalon, and Col, do you have video cameras? -- if you do, you should get a youtube account and post vids of the progress. I think that would be the quickest and most effective way for us to share ideas and show how we each did things. (not to mention add sound into the mix and hopefully some very cool musical demonstrations of the things eventually!) This whole time difference works out nicely. You guys are in Australia, and I am in the USA, so I wake up every morning to find YOUR daytime posts, and I must be posting in the middle of the night for you guys, so you get them all nicely in YOUR morning while I'm going to bed! Wow, the internet is a cool thing. None of this would have been possible 15 years ago! -MRJ STUDIOS

This is how I prep the cores for winding... I use that wonderful plastic from the $1.50 cheap garbage cans and make temporary bobbins. Then I cut holes for the blade and hot glue them on 3.5mm apart. When really spread on thick, the hot glue does hold in the coils without sliding or warping -- it is so strong that you can't pull the bobbins off by hand, only but cutting off the glue. (I do clamp the bobbin a little bit just for safety while it's drying though.) You may notice that my cores are a bit tall, but I will use the excess on the bottom either to mount the unit to the guitar, or just cut it off later. (Heh heh heh, computer case steel is not hardened and is very easy to work with.. ) Anyway, I'm stalled until my shippment of .2mm wire comes in. -MRJSTUDIOS

PSW Ok then, I'm keeping up but I'm stalled in the building process since I am waiting for my .2mm wire to come..... So PSW, are we going for 16ohms instead of 13.5? I figured a 8ohm (total resistance) unit would be best since that is what the F/R is built for and all of the single coil drivers are 8ohm. My Driver is a little bigger width wise than yours, so I should be able to get 16ohms wound on there easily. AVALON Which one worked better, your 2 x 16ohm driver, or the 2 x 13.5ohm driver? I'm leaning towards the 2 x 16ohm version now with mine since PSW was able to fit 16ohm coils on his smaller unit, and a full 8ohm total resistance unit just seems better balanced with the F/R then a slightly weaker one. -MRJ STUDIOS **pictures to come soon of my progress, but still no WIRE!!!!**

Then mine and yours will be the first ones.... uh boy, pressure -- better get it right then. Uh, real quick PSW -- your design is 2 x 14ohm coils wired in parallel with .2mm wire correct? If it is, I was thinking this size consideration would be safer and is what I'm using 14ohm Coil with .2mm wire *remember that .2mm wire is really more like .202mm - .210mm* I just want to be on the same page as you for comparison / testing purposes later. -MRJSTUDIOS

Score COL!! Awesome site!

The wire is new "old-stock," and was only US$6 (about the cost of a meal and shake at McDonalds for those of you who don't use US$$$). Plus, with a dual coil driver using 104 feet per each core, or 208 feet per unit, it would be good to have enough to make 5 of the things. I think the .2mm wire will work out fine, since even the .25mm wire would have worked size wise on a full HB sized dual-rail driver. Does anyone know the dimensions of a 13.5ohm or 8ohm coil made with .2mm wire? Thanks, -MRJSTUDIOS

Ok, just ordered 1000+ feet of 32AWG .2mm Magnet wire!!!!!! So this dual rail driver will be done right!!

Hmmm, I thought I might need thinner wire. I think I'll get some wire in the .18mm - .2mm range, since that seems to be standard around here. By the way PSW, I use the hose analogy a lot when thinking of electromagnetic concepts. PROGRESS REPORT: I got the cores cut out of some 1.5mm computer case steel that seemed unusually magnetic.... and got another $1.50 garbage can for some good looking scrap plastic "bobbin/case material." Now I just need some of that thinner wire..... -MRJ STUDIOS

By the way PSW, do you think my driver as seen on youtube will drive ALL the strings once it is installed? What kind of results did you get with yours?

BINGO!!!!!!!! Thats the good stuff. Any computer case material -- especially the older (non-aluminum) beefier models have great steel in them. Heck, the stuff even magnetizes itself when you drill into it. I also measured and the standard thickness of the case metal is almost exactly 1mm thick on every part! Ok, sorry about my American measurement system..... But good news, the micrometer has a mm setting!! So, my milspec 30AWG converts to .25mm (actually measured) so that stuff is quite thick by the new standards. My only question is... how much performance will be lost, or is it even possible if I use a bobbin that has 7mm spacing, giving the coil a depth/winding height of 7mm? If it is not completely out of the question (as shown in my diagram) I think I will have a go at this whole dual core driver thing! And, you will be able to closely see my work and hopefully save time for yourselves by following my Youtube driver experiments. -MRJSTUDIOS

Ok, so my driver diagram shown above is accurate? And the 6-7 TOTAL ohm driver is optimum and will work ok with the F/R? Just a few more questions before I start this one..... So as it stands I will build a "Dual rail driver" with: 1 magnet situated like a HB 30AWG wire (yes I know it is thick but I want it to be for other experimentation reasons) 2 x 2mm bar stock steel cores bobin spacing (winding depth) of 6-7mm 2 x 13ohm coils wired in parallel Potted with wood-working PVA glue NO SHIELDING (heh heh heh, good call PSW) Driven by a: Fetzer Ruby (with pins 1-8 soldered on full) Running on 9 volts -MRJ STUDIOS Oh, by the way -- My youtube channel is http://www.youtube.com/profile?user=MRJSTUDIOS . This is where I will post my sustainer test videos, and I'll tell you when they will be up. One of my single coil driver testing is up now if anyone is interested....

And by the way, Is this the general consensus on size and shape / configuration? I would use either 32AWG or 34AWG wire (about .2mm, .18mm). -MRJSTUDIOS

This 'problem' you metioned is actually a good thing to me!! Think about it -- if we DID encase the ENTIRE driver in steel or computer speaker material, it would be rendered useless, right? Therefore, that shielding would be extremely effective at completely killing all EMI, (be it to drive the strings, or to stray outward towards the pickups.) SO, if we were to open the top side of this rectangular EMI eating box, the side that faces the strings, we would be unleasing all of the EMI right into where it is meant to go. Could this even help to "channel" the EMField to the strings? Just a thought.... What do you mean by the magned position, and "top / bottom" core? Is the one in the picture really a stacked design? -MRJSTUDIOS

I experimented with coping saw blades -- they do work well. I just prefer a 3mm thick piece of bar stock steel since it is not flexible (even lengthwise) at all. Also, the bar stock is not "hardened" or heat treated like a saw, and it sure seems to be more magnetic, but I have no way to measure or prove that.... Anyway, I'm definitely going to try one of these dual rail drivers, but first one question: Can a dual rail driver be easily made as about the size of a single coil pickup? I'm not sure about their actual size in the previous pictures, but I want mine no wider or taller than a strat pickup. I hope this is possible, and not just a HB sized design..... Also, regarding shielding: I am really getting into this whole magnetic shielding business, since EMI is never going to be completely eliminated no matter how good these things get. I would like to know what has worked for some of you. I was thinking Aluminum is the idea substance since it is not magnetic, is lightweight, and very easy to work with. I have rolls and rolls of sheet Aluminum that is about 0.5 - 1mm thick, so I will use that to layer in my shielding work. My new design idea came from the fact that I need to sandwich 3 sheets of the Al together to get a good thickness; I figure that there must be some substance or field that we can create or put in between the Al to make a nearly EMI proof shield. I'm currently researching EMF Shielding and what places like FermiLab use to contain huge EM fields. Hopefully there is a simple polymer or non-metal film that could be glued inside the Al to create a better barrier. By the way, does anyone know how computer speakers are actually EM shielded so well? And why that technique can or can't be applied to a driver? Between you guy's huge steps in cutting EMI at the driver, the slight changes in the circutry to eliminate EMI from there, and maybe a better EM shield, maybe we could really get to the point of a no-feedback (with pickups) and low-noise driver system. -MRJ STUDIOS

For now, I'm gonna route a single HB hole, and an extra large singlepickup hole for my single-rail sustainer. I don't have a spare HB yet though, so I'll stick 2 extra strat pickups in its place and only wire one to work. I have done some work since this picture, and all that is left to do now is to route the round-over edges, and the control cavity / holes for switches and knobs. -MRJSTUDIOS

Here is guitar #XS002 so far... **The body design is Copyright 2007, MRJ STUDIOS** But I would probably give permission if someone wants to use it for themselves

Thanks guys! I'll take and post some more pictures soon -- whenever the Floyd Rose replacement screw comes and I can have a 6 string guitar again.... Yes, the body is designed built from scratch, and yes, there is white pickguard material near where the controls are. I made a clear scratchplate to cover under the strings though (good call donbenjy). As for the shape of it, it is designed to have an overall Strat / Kramer Baretta kind of size and feel, but with modifications that I prefer over the standard models (hey, it's my guitar, right?) First off, it has no strat pickguard, and the control nobs are arranged differently so that your wammy bar will no longer hit your volume knob. (You'll see later.) Second, the Floyd Rose is mounted about 3mm farther off the body, (which would make it easier to add a sustainer/pickup stacked model), and aligned directly with the neck -- something I call a "flat mount". In otherwords, the action is constant over the entire length of the neck since the strings are not angled down towards the neck from the bridge. Third, the Floyd Rose can be made either full floating or "EVH style" down only with the adjustment of 2 screws. And fourth, the body curve directly below the neck in the picture is cut much deeper than a standard guitar so it is easier to play on the high frets. Not sure yet if these mods would be good for anyone else, but like I said it's just my preference / ideas. If a really stable dual-rail mid-sustainer is developed sometime here, this guitar will be a candidate for it. As for now, I will work on my guitar "#XS002" which is a guitar built around the sustainer. **The body design is Copyright 2007, MRJ STUDIOS** But I would probably give permission if someone wants to use it for themselves. -MRJ STUDIOS

I have not tested it with my multimeter yet, but I believe that the "ballpark" sweetspot on my F / R was probably at about 4 volts. (It runs on a 9v when on full blast.) I'll get it out and check for ya... By the way -- progress on my non-sustainer guitar (so now I can focus on the sustainer one!) **The body design is Copyright 2007, MRJ STUDIOS** It is since put together and plays very well -- except the 6th "hardened steel" string clamping screw on the floyde rose broke in half......... More on that later.....

Yes, I was thinking of building a 4ohm x 2 wired in series dual driver -- and it looks like I'm on the same page as the new stuff, well, sort of. I have already experimented with coil thickness -- my single coil driver (pictures posted previously) has about a 4-5mm thickness, and the core is made of a 3mm thick piece of steel bar stock. I also used a heavier wire gauge of 30AWG instead of the previously standard 32AWG (or even thinner more recently) that is a beefy military spec version magnet wire. I have even done some preliminary experiments using steel/aluminum to try shielding the thing. All of these things seem to be coming into question now, so I would be glad to answer any questions to save some experimenting time so you guys can focus on the dual-coil specific problems... -MRJ STUDIOS

Nice work Avalon! That looks really good -- and from what you say, it sounds like "it sounds good too." -Once the paint job on my guitar is finished and the thing re-assembled, I'll get to finishing my 2nd "sustainer guitar." But for now I just need to get the #1 guitar done so I have something to play.... Sheesh, in the matter 2 months my single coil driver looks like a dinosaur -- but hey, the rate of progress is a good thing.

Thank you Onelastgoodbye! Brilliant! I'm gonna try a side-by-side dual 4ohm sustainer driver (wired in series). It will include (this is for those of you who want specifics for the experimentation aspect): 30 AWG Military Spec copper magnet wire (I think this converts to .2mm or .22mm gauge?) Iron bar magnet (like a single coil pickup magnet style turned sideways) Steel cores (custom cut out of .135in (3.36mm) thick steel barstock) White Plastic Parts cut out of a $1.50 garbage can from Target (great stuff) 'Potted' with Elmers Wood Glue (Yellow PVA) Metal Parts Superglued Together Powered by: Fetzer / Ruby amp from Runoffgrove.com (with pot between pins 1 and 8 replaced with plain wire or capacitor) Running on 9v Signal from a single strat style pickup. Entire guitar and amp circut (- gound) grounded to guitar body. -MRJ Studios