DIY Hex Pickup Project

[JohnH]

this...



John

[4real]

Ahhhh....of course...thanks...

That is exactly what I will do then...a diagram serves more than any amount of words...I should take note and more use of a scanner,

I can see how that works, will just need to get things a bit more settled into a 'layout' for the device...but shows that it is possible

cheers!

[4real]

Out of interest, here is the schematic for rolands GK system...



You can see that there are just simple op-amp preamps and a fairly basic scheme to it. Of course, the 'magic' happens at the other end to turn such signals into a midi signal.

There seems to be a bit of a 13 pin din synth guitar standard and can see these pickups being able to be made compatible.

A 'breakout box' called the "septar" (from ireland, via Gumbo) uses size simple discrete based circuits to pre-amp a GK's pickup for separate audio outs for each string...



rickygraham.com/septar-board-beta-kits-june-2011

There are other "Hex" or 'divided pickup' (which is perhaps a better name) about...piezo solutions of course, the GK things and a variety of custom makers making bulkier more conventional pickup types. Other than the Gk there does not seem to be another appropriate magnetic GK like solution in miniature.

I've noticed that there are some intereting (though slightly hyped) new pups about...like this 'nano-mag' thing that alleges to provide a kind of 'acoustic out' with a small low impedance mag rather than piezo...

www.shadow-electronics.com/web/service/nanomag_technologie.html







My concept might have a similar qualities with the added benefits of separate outs or stereo that individual pickups could provide in a similar style and size...

How 'acoustic' it sounds can be perhaps judged in this video...



Clearly it is possible to make very small pickups if so desired and break away from the old HB/SC formats or even piezo solutions.

I've been surprised in researching how many people seem to be pursuing the ability to get separate outs for a variety of reasons, not a lot seem to be consistent...if one wanted a GK clone, it would be very debatable if anything DIY could compete with a GK-3a at around $175 if you have the technology to run it into a synth or interface.

However, on the audio front, there may well be a whole host of things that have not been explored or even imagined, hence working towards a greater set of criteria than I particularly need for a one off for my project. Who knows what cool things people might make with the possibility to effectively get separate 'outs' from such a device.

...

The series wiring makes things slightly more difficult to wire up, but it is a better solution I am sure and a good point and worth repeating to me till I 'got it' and I see now how parallel wiring may well diminish things quite a bit.

Hopefully the new components will put out quite a bit more power and a better impedance...the test ones were not really noisy surprisingly and tested within inches of my laptop and the valve amp nearby.

The 'novel' thing in my design is that it is sensing the strings magnetically but not in the conventional way of guitar pick-ups...unlike the GK or similar schemes, it is not just a conventional pickup miniaturised. It might indeed have similar qualities to that nano-mag but as I don't know what is in them, I can't really tell.

I can say though that there is very little string pull as it uses something that I described from the sustainer things that they are based on as a 'balanced' magnetic field as I recall...


The magnetic array uses equal and opposite polarities on the string that kind of cancel out the affect on the string vibration. Part of it is making things very small...but it also means that with such a scheme, one can use quite powerful magnets close to the string and gain enough power for an effective signal with very low impedances. Such a scheme though tends not to have a lot of 'throw' so such devices tend to be very close to the string...but then this is common requirements for either sustainer drivers or compact divided pickups.

As you can see from the date of this old diagram, I've had this concept and worked on them from quite some time ago and kept the idea somewhat 'secret' though I did independently verify it at the time sending one to someone to test without me back then and corroborate the claims in the face of 'sceptics' which is all healthy.

Because sustainers need to put out a lot of energy to move a string, there are a huge host of problems to do the kind of thing that the "moog guitar' claims to do and looking into that again recently from interest, their device has a lot of hidden got-ya's like special strings and such required...hmmm.

A pickup however is not putting out energy but sensing and so in the reverse application of the tech makes a lot of sense to explore and builds on work I have already explored. Hence things are coming along at some speed and confidence (though things could all go pear shaped along the way) because it is based on something I have already spent more than a year on and time to reflect on things before revisiting it for this idea.

....

EDIT UPDATE

Received the magnets in the mail, gorgeous but possibly will not be seen LOL...unfortunately, other components still waiting for both aspects of the project before testing and construction can really begin in earnest.

Being able to source components reliably and cheaply is a part of the project and an important aspect. With something as unusual as this kind of thing finding appropriate parts can frequently be something of a problem.

Wiring on such a small scale is going to be tricky too and provide several challenges...the series wiring scheme adds a little too that. Their needs to be inherent shielding within the design to work and wires and connections have a tendency to 'short' if not protected...and any wiring takes up some space...will have to do some drawing and thinking things through.

The magnets effectively dictate some dimensions...in this case a 10mm sq seems to be a given. Depth though could vary quite a bit depending on the wiring and such. Anything can add significantly to depth as such small scales...a circuit board may well be appropriate but adds another mm right there plus the wiring.

Last time I made these things I also found that the magnets attracted the soldering iron LOL...so some fun and games ahead till I come up with some kind of miniature jig.

Will need quite a bit of experimenting and planning beyond just getting the things to work...hmmm...pencil and paper perhaps!

[sumgai]

Pete,

A couple of things to note:

In your copy of the Roland schematic, VR1 is not 50KΩ but is in reality only 10KΩ. This holds true for all four kinds of GK pickups produced by Roland since the early-to-mid 90's: the GK-2 series, the GK-3 series, as well as their Bass counterparts. I know, I have (or had) 3 out of the 4 of them.

Also, in the individual pre-amp sections, IC3 covers strings 3 and 4, and IC4 covers strings 5 and 6.... at least that's the way it works in my GK-2A.

And finally, those individual pre-amp circuits are not all the same. They have integral low-pass filters, intended to reduce/eliminate cross-talk between each of the pickup elements. Obviously then, they are tuned to each string's frequency, and are thus differing values.

I know, small potato[e]s, but if you're building your own, details like that can become the difference between Eureka! and Oh Crap.

HTH




sumgai

[4real]

Thanks for the heads up...not planning on making my own soon but I suspect others will...that diagram came from roland of the GK-2a from roland via www.vguitarforums.com/smf/index.php?topic=4729.0;topicseen

That is exactly the kind of things that I would expect and had heard would be needed to get a good strong fundamental frequency for the interface.

In fact, the preamp for these things may well need similar filtering. That close to the bridge the signal is very complex, the fundamental is proportionally not much larger than all the other harmonics that converge at the bridge.

The basic idea though is reproducible but I am not at all sure if it is economic. What the standards are for 13 pin interfaces is unkown too though I've seen people try and be successful with various odd ball hex devices.

It's good to know though, you wouldn't have the schematic of one of these devices (not that it matters just now as I am not building one and have nothing to plug it into if I did lol).

I'm prepared to do this because...well, it's a nutzy thing to do...but also not too expensive to at least try (I was eyeing off s/h Roland stuff but not in my budget or quite do this kind of thing...they are getting better and better though I see).

The digital effects that will be processing this signal, at least for my application, will likely be able to compensate for things with onboard EQ, NR, Comp and other effects as required...plus pitch shifting and the like...so perhaps one will be able to get by with a fairly standard low current draw preamp design regardless.

As far as I can see from my design, there is very little cross talk if any between strings. It is not like a mini HB or conventional pup as in the roland, a very tight contained sensing field. For my application, having a little cross talk would nt be to disastrous as these things re not aiming really to 'trigger' anything or provide the succinct information that a synth requires so as not to 'glitch'.

There is some potential there perhaps, but I think there is a big potential in the audio modelling kind of aspects to the plan. Not going to make the guitar 'sound like a piano' or anything, but there is still a lot of power in most digital processors that would allow for significant modeling of selected strings and such.

I suspect though that it might be inevitable that someone might try to run a synth off of the thing. In fact, I may well do such a thing entirely in software. Most bass lines are essentially monophonic so if the hex output were recorded on a separate track, free audio2midi can drive a vst of say string bass samples of choice and even be edited out of 'real time'. Perhaps not a performance tool, but a valid and essentially free powerful synth from a DAW. If one had sufficient interfaces to the computer, once could record each string individually and do the same effect on the whole guitar if one chose LOL...probably not yet an effective performance tool.

The intention at this stage is audio and there are lots of application that I can see being useful in several kinds of genres for such a capability. Fairly cheap, bullet proof, utilizes things like stomp boxes that people may already own, low battery consumption, small size without many if any mods perhaps...an alternative pup technology to the conventional mags or piezos...just got to make it happen!

[sumgai]

4,

The cross-talk isn't so much from string to string, as it is from the body coupled via the bridge structure.... what we in the business refer to as "intermodulation". It's insidious, to say the least, because it might not be evident on the bench, or in the test environs, but get the product out to the working world, and sure as Gawd made little green apples, it's gonna show up - in spades!

I've been following your conversations, and I'm confident that you'll both trip across the same stumbling blocks as did Roland, and that you'll also cure those ills, and come up with a decent product. Whether you arrive at the same solution as Roland, or a different one, makes no difference - it's the process of both learning, and turning around and teaching others, that's what makes the world go 'round. ;D

(Not to mention that getting any information out of Roland/Boss is like asking the general populace to vote for someone with morals, scruples and integrity - pretty much a non-starter. )



I should also add that the 13-pin "standard" is pretty much de-facto. Axon, Yamaha and others have all used it, with varying degrees of success (in the marketplace). Those who go a different route are all but doomed to failure, unless they include a sturdy adapter (that's truly drunk/stoned-roadie-proof), a free band van, a year-long date with Eva Mendoza, and a personal hot-line to Clarence Leo Fender himself. Short of that, good luck.

HTH



sumgai

[4real]

Thanks S

just making a circuit board to mount the first one for when the parts arrived and worked out the internal wiring...

I am surprised that that is the problem and there does not appear to be anything in the actual pickup design or mounting to address it...

I've heard of the '13 pin standard' and of course one would want to be compatible...but as yet not actually seen any specs...pickup output and such...

But then, the aim here is not to make a GK replica. It is possible that someone might want to make some kind of adaptor, but I think there is a lot more interesting to be done as an audio device. For roland a lot of issues are required to keep the synth triggers as glitch free as possible and not necessarily or even designed to be an audio device but as a triggering sensor, anything that might interfere with that can effect the performance.

For this project and initially, the idea is fairly KISS really, even if the approach is a bit novel, the result is much the same. The idea is to get as close to the criteria in a post above as I can for the pickup and not rely on circuitry to 'fix things'.

In this application, a little bit of 'intermodulation' is not a critical thing but I am hoping for decent separation all the same...

Appreciate the confidence, hard to tell anything conclusively till I get a string of them and combine them in various ways. I am sure there will be some, even more, frustrations on the journey.

The things are very different from the sustainer's though from which this design stems. In that, a lot of power is put out and generates current in any nearby coils, pick-ups and even ground planes. This strategy was one of the best I could come up to address such things...though perhaps not good enough...hmmm

...

In the background there are some other 'demands' of real life that are going on and looming...this kind of thing though unexpected is a good foil and distraction I must confess, but it would be good to see some considerable progress before things get a little...well, out of hand LOL.

There have been a few tough times and some more ahead, so make hay while the sun shines and all that...

But, for all that can go wrong with this or the guitar project, I have been very surprised at how well things seem to be turning out...a few things I'd like to do better, but for all I wondered whether I'd get a decent sound out of the piezo in the guitar...turned out even better than I'd hoped...

For that encouragement, a postcard...

[gumbo]

4-R...

Between s-g & myself, we probably have access to (or at least highly illegit stolen copies) of most things that Roland have written about the dreaded "13-pin standard" and the associated bits that have been hung off it over the years....

Personal email headed yer way... ;D

[4real]

Thanks G...

Ok...well keep that in mind...got to walk before leaping into the midi world and of course, got to have something to run the pickup into something for it to be of any use. Economically, for $175 aust, a brand new pup would be likely a better bet for anyone going that route.

Still, would be interesting to know some specs and output strengths that the GK interfaces expect. They must be around somewhere for Moore and Parker guitars to interface, let alone ghost and other systems designed to drive them.

For now, it is a alternative audio out and that is something that the GK and like systems are not really designed to do.

I think there is a huge potential in such things and some advantages over some of the other offerings and nothing really but converted GK's that I have seen that fit that bill for a compact hex pup.

The other thing, all being well with this design, it requires no coil winding and the parts are relatively inexpensive though unusual and put into an odd arrangement for this kind of purpose.

The real 'cost' is in building such things that small and not going blind in the process...but the construction can be made to be quite cost effective in the end I think. I don't have the budget for an expensive solution and there is no 'market' for something expensive either...if there is any interest at all in such a device. Anything hand built is labour intensive and you can find yourself loosing money and resources on some hand built 'product'...

Buit, fortunately at this stage, I want one and this is the only way I am going to get one. I think that it is entirely possible that others could put them to such use that I am saying to myself...ohhh...I want mine to be able to do that too.

...

It occurs that perhaps no one here knows of the 'hex sustainer' era in which is spent pretty much all of 2004 exploring without the success I had hoped, but learned a lot in the process...this is a chance to recoup on that investment perhaps and sooth my soul over it with a different application...



This one for example was 5x5mm and contained six independent drivers, 12 small magnets in an aligned array and even 5 LED's seen here lighted...an aluminium case and...well, more... all made by hand...

They were insanely difficult to build and completely impractical and certainly not DIY...though they did kind of work, they had quirks and virtually worked as one anyway...

Better to go for an easy to build design with a single coil was my conclusion that many can actually use than to pursue these things...hmmm


I learned a lot about making some unusual things and working in miniature and the benefits that can be gained by that and about some exotic materials and options.

I thought that the hex things were the way to go, but the DIY model worked so well that went on to be developed into my tele's driver that surfaced mounted and the 'wafer coil' that is a sustainer driver only 1mm thick and completely invisible...and all designs met the criteria and more in the end...shame it took 8 years to get there...I don't know I will have the patience to spend another decade on these things however, so I better get some reasonable results in the end....

Not quite the 'product' that we had hoped to make out of the hex sustainers, but a success all the same...



But a pickup, that is a different kettle of fish and the concept is the best I can think of that matches the criteria i set which is a tall order. However, better to aim high and reach something that is acceptable and find workable solutions...than to aim low and at best make something that has no practical use or takes a lifetime to build and a lot of money in the process.

A few years have past since 2004 too, I've got a little bit more experience and had more luck than I had back then in terms of supply, costs and how to work things a bit easier. The first one will of course take weeks, in fact it already has, but that is the price one has to pay...besides, it has me hooked for the moment and if I don't build it, I don't see anyone else doing it!!!

Thanks for the interest everyone, thre will eventually be some kind of result LOL...

[Billw100]

ha!!! I finally found you, and your doing some of the things I was getting into 5 years ago and let it go.

I still have my g2k1 semi apart from trying to fun individual piezos through it.

BTW I built your sustainer over the weekend. Having issues with the G B and A's but only made 2.5 coils so far.

Anyhow, keeping an eye on this one

[4real]

Hello billm90....

Do I know you from another forum?

Anyway, can help with the sustainer, generally do that stuff privately by email so welcome to contact me that way of PM, sounds like a few common problems. There are things that are not clear from the threads such as the circuits 100uF output cap, but your problems might stem from something in the driver construction by the sounds of it...fell free to drop me a line.

...

And this project, well this is revisiting stuff I was doing back in 2004 as well, many have attempted a solution to these things.

In many respects as far as outcome the aim is to produce something very similar to the GK pup though different means...the format and size is likely similar...

At least in planing, still awaiting parts as the concept is somewhat exotic but so far testing has been done with the old sustainer components, the design upgraded, better supply of better components and upgraded hopefully for a better signal out over those tests.

This is initially part of the 'concept guitar' currently active on the forum and well advanced, currently in the electronics stage as well.

For a starter, the 'hex' or 'divided pickup' is to be able to get a separate audio out of a selection of strings. Strings are selected from DIP switches in my case built into the ends of the pup itself and is mono.

This enables one to select say, the bass strings, run them through a pitch shifter to get an octave below that will follow the guitar in solo guitar arrangements. Rather than just cover two or three strings, I decided to do all strings as there are obvious other applications even for my use.

Another obvious variation would be a stereo version. In this case, the switches would select which of the two stereo channels they output to and can be processed separately, the format would likely be very similar.

Building a fully hex things with 6 outputs means six preamps and assorted cabling and perhaps processing. There may well be people who would like to explore such things and to drive perhaps a midi capable system. Being able to get good separated signals in a practical and affordable manner would appear to be the 'missing link' for those with the ability to design further in that direction.

With a GK though, they already offer the control and interface required to reliably run their synths so I am not sure there is any advantage in bending something like that to those ends. There are already piezo 13 pin compatible systems too, like the Ghost that can do that side of things.

This concept and variations on it may well have a lot of applications though and some select appeal. Rather than just spend all this R&D, time and money developing it only to make one speciality device just for myself, and depending on the economics of creating them, I am likely to make some available to those that can put them to valid applications and further the concept and refine the design.

In fact, these things are a new kind of pickup and can see a range of ways they could be incorporated into conventional guitars, even acoustic instruments and for some artists be of use so there might well be some kind of limited hand built 'product' at the end of it. It is no longer a DIY project though in that regard nor if the current course of action successful will I be revealing how they work...more's the pity as it is hard to work in a vacuum.

I do though have several back up plans and some of those two are likely to be explored and may well lead to some other very interesting results as alternatives to magnetic, piezo, optial or other ways of sensing string vibrations.

...

SO for now, the plan is to develop a device that is reproducible and fit my criteria for success, serves the simpler approach for what I want the things to do and prove that on an actual instrument (in progress) and field others on other applications and improvements that could stem from a prototype.

Parts for these things are not easy to get nor exactly cheap, working in miniature even more of a burden, getting something 'polished' as a product another thing still...let alone the circuitry side to make them effective...early days yet, plenty of places to stumble.

However, nearly every component needs to be ordered in minimum amounts of 50 and a requirement to even test the effectiveness of the approach...so I am likely to make a few variations right there!

As of this stage, the concept is tested and the principle sound. They are very low impedance and will require pre-amping, from the tests though they seem to be hum-cancelling in of themselves. The improved components and magnets are likely to give them a better output than a sustainer driver in reverse and decrease the size of things which should improve function.

I've nutted out the valuable contribution of people here to run the devices in series with my application and have prepared some jigs to make construction possible...but as I say, there is no point experimenting further till they arrive.

There is a remote chance that I could revisit the concept of the 'hex sustainer' from which this derives which combined with this 'hex' pup may well create some interesting results, much like the moog without all it's problems (have to use their special "moog strings' and have a lot of $K). In many ways six ebows with improved polyphonic response...but sustainers are a bit of a curse, I personally rarely use mine in a musical situation and far harder to do than any pup technology. But there is a possibility.

As I say, due to the problems that public threads and posts or help with sustainer inviting trolling and worse, I freely give of my time to help and support the project for non commercial private use sincere DIYers via email as I choose and generally do so for a couple of people at any one time...since I started it, I feel obliged still!

Be assured, despite detractors, that dozens have successfully been built and the device can work as described. My telecaster in the gallery here with sound clips and all is an example of the basic DIY Sustainer design built to a 'professional' standard, but the principle and results can be made buy those with a will and an eye for detail, circuitry building, wiring and some 'arts and crafts'.

guitarnuts2.proboards.com/index.cgi?board=music&action=display&thread=5318

You definitely should be getting a response from all strings, low to no distortion or 'fizz', response in fundamental and harmonics modes from the lowest to the highest frets and regardless of strings. In fact, generally the G string, followed by the B is the most active if followed my design and circuit suggestions...



The above picture of my tele with the sustainer on shows the driver (the kind of tight wound and well glued result required, even if in a bobbin)...you can see that in the time to take the picture and without touching the guitar, the g string is moving strongly on it's own, the high e appears to be moving next most, the B and D strings a little. Low strings always tend to be easiest to drive due to their lower tension and higher metal content, so I bias things to balance things out. Due to trolling and endless bad attempts gone wrong, how to do that to make my design work as intended pretty much got lost, but as I say...drop me a line and it could well be a fairly simple solution or I might have other suggestions.

...

I'm keen to hear about ideas for this project though, especially if you have attempted such a thing before, ideas for applications for such things, expectations and formats for such devices...everything really would be of interest.

Welcome aboard... p

[4real]

Well, the long awaited parts to have a go at the first prototype of this version arrived and intend to build it into something 'workable' with plans on how to do it with the wiring in series as john and others so well convinced me.

Some tricky wiring using enamelled wires to keep everything compact is ahead of me...perhaps if I were to make these in any quantity this could be carefully printed on a circuit board and save a lot of labour

Unfortunately, at this stage, I don't want to give away exactly how the thing is supposed to work other than they are magnetic devices, but the tiny 3 spst switches came in two and ideal for this application so I suspect it will 'look good' all the same.

Anyone any thoughts on how to get a circuit board to gently curve into a 'fretboard' radius?

Perhaps tomorrow I will have a little time to give the things a bit of a go and see where things lead from there...there is of course the possibility that this course of action is a bit of a wash out, but I am hopeful...oh, and have a plan C...or are we up to D already?

I just had a brisk look through some of the posts here, I note sumgai's thoughts about intermodulation...it is a risk and especially on this host guitar which is kind of acoustic. I'm not to concerned though for my particular application, but will have to see how much it could be a problem for others. There may be design possibilities to cut things down a bit if it turns out to be problematic.

Still awaiting parts for the host guitar, but been playing it a bit and a little loathe to take it apart to work on things too much. Other life things and all allowing, and some parts coming hopefully this week, I can at least make a start on that aspect...perhaps this and it will merge at the same time which might be convenient...

Hope people are still interested in the possibilities of such a device in some form or another.

[gumbo]

Good that the stuff's finally arriving, 4R...

FWIW, the Roland GK3 PCB (albeit not all THAT wide) adjusts to the fretboard curve with a central screw through the housing...

..the 'bending' of that seems to be less of a trouble than the cable breaking at the connector end, if you recall some of the 'GK repair' posts over at V-G...

Talk soon...

...and no, we'll never get sick of this thread...haven't you worked that out by now??

[4real]

Ok...feeling a bit better today and the parts finally arrived. Did a little revision as to actually construct this thing now that I can actually play with the real parts...hmmm

Understand like anything, although there have been encouraging tests, this is a new approach and plenty of things can go wrong...

Also, that after testing, the initial prototype will be designed to do the specific thing I want for my application...that is to be able to select to a mono output which strings are to be 'picked up'.

There are many variations on what this kind of technology could be bent to and the definition of the 'hex' thing...which should more rightly be called a 'divided pickup'.

Some variations that come to mind is a pickup array that allows you to select which strings that go to the output, no output from other strings.

A stereo version of the above, so that you select which strings say go 'left' and which strings outputs 'right'...a further elaboration could perhaps be like the old 'ripley guitar as used by EVh at one time...



www.vintagekramer.com/ripley.htm

This one designed and used by Rick Vito who I've always had a soft spot for as a player and guitar designer...



There are six pan pots to send the signals to separate outputs and two amps...

The other of course would be something that has six outputs, like a GK pickup and such might need for separate string processing. This would require at least a pre-amp for each string and so complexity goes up and there are quite a few things that might yet be required it to meet the 13 pin synth interface and all that...

...

So, for now, the idea is to keep it simple.

The concept fairly crudely tested with ferrite magnets and other components that were selected as a driver rather than a pickup and without the 'noise cancelling' features I am now working into the design concept from 2004.

The next step is to use components and magnets I feel might be more suitable and reduce size while increasing signal strength and sensitivity.

The curvature thing, well, I am not making nor would it be particularly easy to make this adjustable, possibly it will have a fairly generic form of curve in these early forms, the first one which is designed for my project guitar, has a very flat wide bridge and could well be 'flat'.

Given the hand built nature of the device, especially in the early stages, the first prototype may well be 'over large' to what it ould or can be. In fact, now I have the switches and other stuff, I can see that the DIP switches are by far the biggest components and will determine the overall depth of the device...unless I wanted the switches to be proud of the string spread, which lets face it would get in the way.

In a device where the switches were not to be built into the pickup itself, the design is very sleek, even in hand built form...but, the wiring from it complicated with many fine connections to do the kinds ofthings I intend, so keeping all that wiring internal and perhaps one day handled by a printed circuit board seems to be the neater and better approach for my application.

To take six signals out, that would require a fine multi-core cable containing at least six wires and a ground shield. Has anyone ever seen such a cable, or think of a different compact solution?

One thing I have done before is to use enamelled insulated solid wires and a few grounds of the same and twist them together and shrink wrap the lot but I think it would be preferable to be able to source something a bit less labour intensive and reliable...though, that is an option that I throw out there to cultivate ideas from the brains trust...

Ok, shower, more coffee, check the mail (something I dread these days) and get to work on this stuff.

Oh, and a shout out to bane and his DIY layout creator program. I got the new version to work (not sure if I didn't like the older version better however, hmm) as this can help a bit, even with a project like this...

diy-fever.com/software/

He also did my sustainer years back and the tutorial of that is also on that site...

diy-fever.com/misc/diy-sustainer/


While the sustainer has been mentioned here and the technology I am exploring here is related to the work done in 2004, it answers a question that was always there in regards to those 'hex' sustainers...how does one get six signals out of the guitar to run six individual string drivers, even if one could make six string drivers.

There is some interesting potential for combining the two devices in this way, not sure that I really want to get to stuck into sustainer development these days, I personally don't have a use for in in my own musical direction and the far simpler version I have created do a good job without the complexity and hair loss. However, it does have some interesting potential and despite the complexity does perhaps offer some benefits in other areas as well and there is the possibility of the two concepts merging though to get into sustainer's as I say, is a risky public and private enterprise that would take a lot of work and without even a clear benefit to me which at the very least would be needed to get the enthusiasm to spend a year developing such a scheme...again...

...

But I do want a basic version of this concept...so better try to make it happen...will report back later as to how that went as a first try... p

[4real]

I spent a lot of time today, most of it fact, but onlu got perhaps third through the prototype.

Rather than go to more 'testing' I've gone to a full prototype of an entire array with the new components, much of the time is to make something that has never been made before and with material I am unfamiliar with or not used for years.

What would be ideal would be a double sided printed and drilled printed circult board...but that is not going to happen yet. So, instead, I am using a sandwich of two vero boards for this one. I may even be able to include a layer of 'damper' in an attempt to address sumgai's concerns in the prototype.

I am unable to show production shots of today's work however, as that would give a little too much away and of course, this is a hand built prototype so, there are some rough edges to make things look 'impressive' but I have to say, it does look 'impressive' so far and perhaps pictures tomorrow after the epoxy, an important element of the design is fully cured and a 'finish' applied and the magnetic array installed.

The pickup/s themselves are mounted on their own circuit board, so I should be able to show the small size of them alone and how they might be used, the one below the switches and wires between.

The main new components, while still producing a low impedance, is many times greater than the original concept test as are the magnets without producing string pull...so, theoretically tey should prodce more output...

I'm glad that people are interested, it is very hard to gauge with things like this if it is simply 'interesting' or desirable' enough to make more than one for myself...but I anticipate developing it more all going well...and indeed have another strategy in mind that also might produce some interesting alternative results.

Stay tuned for the first picks that will clearly show the concept in soem kind of tangible way, regardless of te results achieved of the very first incarnation of the things... p

[Billw100]

I am trying to keep up with a few topics here, so I may have missed it. Just started really reading around here1 hour ago.

Has anyone tried using those phone suction cup recording devises? They have a coil inside. I dont know if it would be a decent option to try hex stuff with???

Maybe if you rewound them with thinner wire?

I have seen them for around 2-5 bucks each. They look like this.

[4real]

No...but I have seen them used to create a DIY ebow.

I doubt that they would be of much use in this application, possibly not even fit... (there is a max of 10mm betweens strings and you need to limit the possibility that anything is going to be close enough to pick up the vibrations of strings on either side)

In response to the simple approaches and hacks like the tape heads, which did give a signal in their own way, I am now making a more revolutionary device and perhaps "product' that is far from DIY but would have many applications and perhaps be the 'missing link' that many need to make other ideas work.

This is expensive and time consuming work even to test such ideas and on the back of years of the same to even be able to attempt it.

...

Anyway, since I am here, I can say that I am close to having the new 'divided pickup' array finished to a point of being safely able to show exactly what the things can look like...though how much testing and further fine wiring might take a bit longer and there are still quite a few 'ifs and buts' and still fielding potential interest and applications.

As I say, not a DIY project in the direction I am now taking...but certainly a potential important element in exploring all kinds of areas.

And, I am impressed with the look and functionality for the thought I've put into this new approach so far and hope that when I do show something of it, probably later today, that people will get a better idea of this thing and see that it is quite a unique new kind of pickup concept and feed me more ideas...

Of course, it too could all go 'jubblies up', but I am hopeful enough and will find 'a way' that is an effective solution in time...

I just got a mail this morning telling me that I should tell no one anything, and after the whole sustainer thing, perhaps there is some point to that...hmm. So. understand that I may not wish to discuss how the things work or show pictures of the construction methods or even detailed principles...but like so many other generous people on this forum, am keen to share and collaborate...

Because of the limits of space, this kind of thing takes fine work, at least in the kind of device and performance I am seeking. Other than perhaps the roland GK type devices, I've not seen anything quite succeed in this task though there are some commercial 'hex' pickups of more conventional format and technology about.

The paint is drying on the thing now, so be a few hours till I can assemble it, take pics and show it here...stay tuned

pete

[4real]

FIRST PICTURE

Progress so far...as promised...

Unfortunately, had a rough night and not well, and these things are very tricky and there has been a lot of 'problem solving' along the way....these things are pretty small, so this picture may be larger than life, and not quite as neat and professional as I tend to aim for...and, excuses, excuses...here is the first prototype array, to this point and untested (though it did survive the construction process)...



It measures exactly 9.17m wide, 60mm long and 5mm deep...not bad for a first go! You can see that the switches I am using are exactly the same size there and a little deeper...this array will fit exactly between them and level with the switches on another circuit board and the fine wiring yet to do between the board the array is built on.

My string spread at the bridge is fairly flat anyway, so for a prototype, I have built it flat, they are hard enough to do as it is without adding a curve.

Clearly I am protecting much of the design by not showing any of the underside connections and such and will continue to be somewhat evasive.

I am quite keen on the format and 'look' so far, even if this one is a 'little rough' it did take two whole days and for a first one and learning experience, not bad I think and true to the 'design' pretty much.

...

This is a mono version, so those little switches (one around the wrong way there I see) will slide towards the pickup/strings to select which sensors are activated, go to a preamp with a simple volume control and out it's own output for processing and amping...

In many ways, this is a far more complicated approach than simply taking 6 individual outs like a GK. Obviously in that, the switches are not required but some space on the ends may be needed for cabling.

There is absolutely no spare space in these things and could be vulnerable to damage except that the entire thing is a solid block of epoxy...so, there is no 'screws' or the like and no ability to bend them once built...at least like this. It might be possible though to make the sensors in six duplicated parts though, so that they could be mounted onto something a little flexible.

Although these tiny magnets are extremely strong, this sensing design concept is quite novel and uses what I used to call a 'balanced magnetic field' when I made the sustainer driver versions. Basically that means that I have opposing magnetics towards the strings so the string pull is low. This allows me to use such extreme magnetics.

I liked the 'look' of the centre magnets so much, I could not resist showing them which made things a little harder to construct so might reconsider that and built the whole thing in some kind of jig and mold it into a kind of monolithic 'block'...

An almost amusing, if any one were to see it but not be in the way, is that in trying to arrange the magnets into the array, the central ones are all opposing and as I added more into the slot to line them up...the end one suddenly shot out the end...apparently these things double as a 'rail gun'...hmm.

The internal parts too can get a little fragile and the epoxy encasing (the black part) is very much a part of the design and required for it to work as intended, let alone to hold all these opposing forces in check.

This is NOT a DIY project for general consumption, but it could be an important component to be used as such, so still looking for ideas and expressions of interest in developing the things further.

I've also had a rash of sustainer enquiries, so there may be things on that front to make things a bit easier.

As I have said, this is based on the 2004 mysterious (and will hopefully remain so) "hex sustainers" that I was developing. The exhibited a lot of 'quirks' though was even smaller than this. Since then and in revisiting in this application, I have made some significant improvements.

I even have quite a few exotic components and materials used in making them, some of them used to develop this (though this is more optimised for a pickup). One invariably has to think...hmmm...should i revisit this concept with the upgraded technology and knowledge and build a comparative sized surface mounted 'sustainer array'?

...

Anyway, 2 days solid work...pretty much....several weeks in development, if not months, the entire year of 2004 and more working out how to do this.

There are a lot of 'production' matters required to make this actually 'productive'...a double sided printed circuit board this small would greatly ease the wiring and other aspects, likely reduce the height some what (I am using vero here). More elaborate molds, a more suitable epoxy, jigs to stop magnets flying about and get perfect alignment (even super glued in you can see how the forces at work have pushed some of them about a little).

...

And, lest we forget...this is not finished nor tested or shown itself to really be suitable for this application...hmmm...

So, what we have is a testing of the principle and some back research and imagination and a completely 'off the wall' original approach to magnetic sensing and production. Some more recent tests of the principle with more conventional magnets and less that ideal components from a different project (basically a sustainer in reverse, so not ideal) that produced a signal without the 'quirks' I got from say the tape heads.

The task requires working in miniature, there is no way around that...there is a 10mm space between strings and a string on either side vibrating. If the sensors inter-relate (say in a common magnetic field) there will be cross talk. If the sensors are of a significant size, they will be close enough to the adjacent strings to sense them. Some cross talk may be inevitable. In testing though, I was able to have one under one string and heard no signal from an adjacent forcefully plucked sting, so that is a good sign, but the test models were only singl strings, not an entire array, so that remains to be seen. For my application, some minor cross talk is not a deal killer at all.

The sensor need to be close to the strings and near the bridge ideally, I was getting quite a nice rounded and more powerful signal in testing further away, but that can cause problems in separation and of course string bending...so there is less vibration near the bridge. although the magnets are 'balanced' they are powerful and so one can't let them get too close, things stick to them and waving metal over them, you can definitely feel them...I believe this will be ok near the bridge...possibly I went to far and might need to scale things back in that department in a future version...have to see.

Anyway, it is a bit like giving birth and something of a thrill to see something like the thing in my head emerge into some kind of reality and to share the 'baby photos' with you guys. It is hard to work in isolation, doubly so with a lot of these things as the ideas are new and there are no like minds or musicians about and because...well lets face it, I live on a cliff on a freaking island and outnumbered by penguins over people anyway!

Sometimes, despite the beauty of it all, it does get to one...been some stressful times of late too and now a passing illness...so shortly back to bed I think...hmm...don't worry, a passing thing...hmmm...fortunately as I just heard they did away with the only ambulance for 100kms from the island...budget cuts (the average age around here is about 60 most of the year is seems and in summer, the population goes from about 6,000 tops to well over 40K, largely young, naive and occasionally drunk and with kangaroos that have a kamikaze streak and jump out at cars at dusk at the drop of a hat (recently, off island, one jumped right through te windscreen and landed in the front seat next to the driver!)

ah, but a beautiful sunset...lol

...


Anyway, lots of ifs and buts and things that can go wrong...

This picture though gives something of the idea and how I am imagining the device and be really interested in any feedback or opinions, applications or improvements, suggestions, criticisms or of course compliments.

Thursday here, and away for the weekend, so things might stall for a little while, but hopefully next week I will do the wiring and assembly and develop that whole process, hook up a preamp and get some sense of what I really have here at this stage...


later then... p

[Billw100]

I think it looks cool. I have no idea what is in it. I am not really able to imagine what it is. well I could based on knowing it has to have a coil???

I read your post, and imagine you with some sort of magic epoxy, metal dust and a microscope.
I know how frustrating putting these small things together can be.
I tried doing all sorts of things with piezo buzzers, and just wore myself out on it all. I must of wasted at least 150 of them, and I don't want to look at them anymore.

If you need to keep it secret, well at least once it works, make a recording.
You mention the magnets... did you find some that are that size, or did you have to work on those as well?

[JohnH]

Looks cool! Looking forward to hearing a strum or two from it.

If you can get a recording with one of the other pickups, and this as a reference, at the same recording level settng, we can work out how many db of preamp gain you'll need to match them.

cheers

John

[4real]

Thanks...

Hard to do that with the host guitar still being acoustic doh! I think perhaps I should get the 'test strat' out of mothballs and see if it will fit on that.

I have also been wondering, these are very low impedance, does that have an effect on circuit choice?

And of course, the impedance changes with each new pickup in the array turned on, should there be some resistors perhaps in the switching bypass perhaps to keep things more 'level' in that regard?

Not sure how much 'testing' I will get done in the very short term (will be away, a little dehydrated from the other night, etc), the readings on it shows that it was not damaged by the construction though.

So, will test the array as a whole and individually and various combinations before attempting to wire the switching with the preamp In used before to compare with the previous tests and if these strong magnets have had a detrimental effect to things...and the thing 'works' in this new form...cross talk and all that...

The prediction is that they will provide a greater signal, but being so close to the bridge, the string does not move a lot, so the signal there will obviously be less and quite 'treble-y'...something to calm these higher harmonics might eventually be in order perhaps as well as a lot of gain.

I don't think I would get anything much out of the things 'passively' and confess I never tried that, but then at this low an impedance there did not seem much point, is there?

...

billm90...that's not too far from the truth, the dining table is a mess again, I don't have a microscope but a giant magnifying glass...and all kinds of things...

On magnets, no sourcing materials and components are key to this kind of thing. warning NEVER attempt to cut or squeeze magnets, especially neodymium and scintillated rare earth varieties. For one thing most magnets will be damaged from grinding and heat and such, ferrite seems impervious to cutting and grinding anyway, alnico will loose its magnetism (fender style poles are generally magnetised in the pickup, etc)...but rare earth magnets in particular....well, they can kill. Consider the power in such a small space and what would happen if you had tiny shards of these things suddenly released all with opposite poles...you definitely don't want to go there...

Any magnet can be dangerous like that or at least be rendered useless. Strong rare earth magnets too have very specific uses, the energy is strong but extremely condensed being attracted to itself and if used conventionally in pickup design, other than in very small doses, tends to attract more t itself more than ever gets to the string...if it does, it would suck the string down on top of it...doh!

Back when I first worked with them, I think I 'calculated' crudely that a disc 5mmx1mm had a similar pull to a strat pole piece 5mmx10mm...but that is pretty rough...but all the energy is condensed into a very small space and even if attached to a 'core' the energy tended to just come out sideways and back to the other side of the magnet...lest one think one could just attach such things to the bottom of a pickup instead of a ceramic magnet and 'mojo' the hell out of it with the words 'rare earth'.

However, when working on this kind of scale, and in these kinds of novel ways, there are few alternatives and at least one can get small magnets if one knows where to look...though not always the size you 'want'. So, I design things like this around the components that are possible.

Such a venture is also not 'cheap' and to get to this point has been at least $100...so it had better 'work'...but the price you pay in many respects and the 'risks' can be great. I enjoy the achievement and the imagination, but I am not sure that I really enjoy the 'process' of building things other than it creates something in the end and a bit of 'pride' in creating something new...discovery and all that, like an explorer.

The ideas for this kind of device actually came out of the 'sustainers' and I must say I am curious that in 'reinventing' this, whether I might have solved some of the problems I was having in those devices...I had a dream last night, before I head off back to bed again, of an HB pickup ring, slightly enlarged that included some kind of 'array' like this into the sides...ah, but I have had that dream before ...errrgh... *shiver*

[JohnH]

Pete - the fact that they are low impedance is a good thing. For a given output voltage, it is much easier to create a low noise preamp with a low impedance source than with a high impedance one. If they are just a few ohms, or anything up to a hundred or two, then you may be right in the range of working with a microphone preamp circuit which might have an input impedance of 1 to 2k. Ie, its a relatively low input impedance but still much higher than the pickup. There's no need to splice resistors into the chain to try to match or maintain the Ohms.

[4real]

Thanks John, that's what i was thinking was the case

I am not sure that it means much with these things as they are not directly comparable to conventional devices, but each 'pickup' is about 32 ohm and the total about 180k when run in series.

Gumbo sent me some stats on Rolands GK devices...

Basic Hex pickup information.

DC Resistance ( per pickup ) is 96 Ohms.

Inductance Value is 330uH ( micro Henries ).

Flux per pole face is 700 Gauss or 70 milli Tesla

Looking on top of the hex pickup with the cable entry on your right, North pole is top and South pole is bottom. The two coils per string pickup are humbucker connected, to my best knowledge.

Not that it matters or I can take such measurements...

I think the impedance of my device is much higher and certainly there is a lot more magnetism in there (might be too much) and they work in a different way and format...soo...means little really, nor am I rally trying to make something like that, but it is the only really comparable device of this nature and eventually it might matter to some...

So, that's good news...

I found and ordered a chip to play with, but perhaps not the best thing...but very easy low parts count to run it and very low noise...

www.analog.com/static/imported-files/data_sheets/SSM2019.pdf

I'm not sure if this might be a way to go or be too power hungry. I only need one preamp for my application, the next one will be in stereo so two, someone wanting an individual hex system will need six and so it goes...so I am thinking should things expand that the parts count and such might need to be addressed as much as the power consumption...but then this is not my field clearly...hmmm

So, might be a few days till I can do much on this as going away...but again thanks for the reassurance

[4real]

Well, not been too well today and going away tomorrow...but I just tried this thing with the same preamp as before and holding the things above the strings....hmmm

Well, it certainly is more powerful and gives a decent guitar level signal if a bit 'bright' being that close to the bridge.

However,and these are crude tests, when you twist together the wires to bypass in series as suggested, there is quite a lot of 'cross talk' between them really...hmm.

The original ideas were to test whether this novel and compact approach would get a signal and to that extent is something of an achievement, a completely different way of getting a magnetic signal from the strings...

However, the point is in the application so I will need to put some thought into things while away perhaps. Could be that I 'over did' the magnetics, perhaps the sensors need to be even smaller to avoid corss talk...

To sick really to be thinking about it, so will give it some space to breathe...any ideas would be appreciated, as expressed earlier, a perennial problem, but these are crude tests and a 'first go' so perhaps I will think of something more 'creative' or some other approach that might be better pursued to get the result I am after...

[JohnH]

Well those little magno-blobules are pretty close end to end. Would it work if they were rotated 90 degrees? How about if it was in two strips of three, each with a gap?,

[4real]

Yes...well, I think that the magnets are perhaps over done. These things are not cheap and min order to get things and only come in certain sizes...hmmm

Magnets do tend to be attracted to each other regardless of the space between, though I was hoping for a bit better performance with this novel design and from the initial test indications. No, wont work oriented another way I am afraid.

I had a dream last night of a 'twisted field' though...using yet more magnets, smaller and arranged carefully so that between these magnets, the field is' twisted' into a kind of spiral between and perhaps in that provide some separation. The restrictions of space require this kind of thing.

...

What matters is the results though. The signal is very good, with the basic preamp on par with a normal pickup and the signal quite a good audio representation of the strings...in that respect it is a success, if separation were easy, others would have done it...there is about a half volume decrease with things being wired out of the picture...perhaps there are other means like phase cancelling out adjacent string that could be contemplated.

On the other hand...there are a lot of other approaches that could also be done despite my fondness for this original approach and the work done on it.

I'll be away for a few days, so perhaps I will get some more ideas, the tests were quick and crude and done under some duress, so perhaps there is more to explore before 'jumping ship' on the idea or this particular approach.

...

I've had a heap of interest in sustainers and this new version of this technology, even the magnets used, could well be explored in that area...not that I have made 'sustainers' for a while and resisting getting dragged down that rabbit hole too far, especially with this kind of 'pure research'. A similar device though would make an interesting very compact sustainer driver however for surface mounting...so...maybe...

I might see if there is a decent way to offer 'kits' of some sort for the DIY version to make things clear and the parts easier to get and perhaps recoup something for the hours put in every week for free helping and clarifying the mess that that became.

Not sure what people think of such a possibility and what kind of money people would be prepared to pay for such things...but a possibility and canvassing opinions or suggestions via email perhaps for now...

thanks...time to go and let it rest and hope something 'pops' into my had on the thing, I certainly still want one of these things...so...hopefully a way will be found with some more work and imagination and within my ability and the assistance of others...

p

[JohnH]

one simple test you could try would be to offer one end of the pickup to just one of the outside strings, so that the other 5 units are not over strings. You might learn more about the range and interaction of each individual element wit hothers. Also, as it approachs the string from the side, at what point does it start to pick up?

[4real]

Thanks john, about to leave

There are more tests that could be done on this of course and need to give it some breathing space...try a few things...

In the preliminary concept tests, I got little cross talk though that is not conclusive and the other strings were not also included much in the magnetic fields.

I played around a little with some of these things both in the preliminary tests and this one and of course with other projects...it is just one of many catch22's with this kind of thing...anything with magnets have a tendency to interact.

I was trying to maximize the signal coming out of the things and perhaps I went too far with this version getting a good strong signal, but more interaction. Largely I think this might have a bit to do with the magnetics, so more work needs to be done in that way.

It is tricky to play with things too much in this form, so will attempt to work out a different way that is more flexible to tinkering with the concept as there is clearly potential to the technology IMHO.

Perhaps the quest to get a stronger passive signal and higher magnetics was a little misplaced...this is where I come across a lot of my deficiencies with things like the circuitry side of things.

It would be interesting if some thought was put into using phase though to cancel out the signals of 'off' strings that might be picked up in an adjacent string/s.

I do have a few other novel ideas that might be even better, possibly easier to make and potentially smaller.

To hedge my bets I did get 'one' vital component to play with and test and could be a bit of potential there too...different again in approach to both this thing or conventional pickups. Though, quite a bit more expensive (hence only getting one). I've suddenly been put under some financial stress and live a pretty frugal life, so have to keep some of these things in check these days...

Plus, it is easy to get so distracted by the technology and neglect the musical side of things and of course, the host guitar needs a bit of work both structurally and electronically...plus all the actual playing time and associated work required.

I had always attended this to be an addition proposed to that instrument, interest by others extended the criteria quite a bit (for instance, if I only wanted a tiny pickup for the two lower strings, this device covering just those strings would do the trick and 'cross talk' is not so much an 'issue' for my application...but six would offer a whole lot more and the less cross talk the better).

Anyway, an interesting start, some new technology, works as a pickup and that is an achievement and the right kind of 'size' and some other advantages. It fails only in the separation thing, so in that, it has come a long way pretty quick...weather it can jump that hurdle or a completely different approach is something of a question.

On the host guitar, still awaiting those double ganged 470K pots and being in the mood to play about with that side of things and make decisions on the plans for it. I may add a tone control as that 'third knob' perhaps, or leave it off pending a break through with this project.

Any ideas though, while I am away will be appreciated and it is hard to work in a vacuum of course, so the feedback and interest helps a lot.

The sustainer thing too, interest sometimes waxes and wanes, but I wonder if there would be an interest in such things amongst this crowd and regardless, things like costs and formats that one might think might be worth my while offering...the volunteer work is getting a bit much at times and a lot of it could be cleared up with a more direct, do this, with this, get that kind of approach that is the primary cause of failures...

ok, I'm off for a little while... p



advice for the day...dont get the wrong end of a koala...

[4real]

Back again from a trip away and a bit of 'thinking' and better yet, not thinking too much time...

I am looking to try some smaller magnets with ore of a gap between the pickups magnetically and see if that helps with the separation issue...perhaps my strategy for addressing that with this device was underestimated regarding the interaction control..hmmm..at least this experiment means that the same device with new central magnets might provide more of a clue there.

I can think of combining at that with still another strategy of orientation that might help, but I don't want to make these devices too large.

Alternatively I have some thoughts on other types of magnetic sensing, so might play with that too, this means smaller magnets again, so it will take a while before i can locate and get something suitable.

...

I've received a bit of 'sustainer' correspondence, so as I am playing with magnets again, may well explore some of these ideas on the opposite end of this kind of thing and see if there is some potential there or ways in which I can make that device a bit more accessible as well.

...

I just got a call at 7 in the evening from some poor hapless element14 courier who could not find the place so apparently the missing pots have been caught in that, most things arrive by post via the post office as there is no mail, but somewhere wires were crossed and they insist on driving 2x pots directly to the door...hope the driver brings his surf gear, 32C here tomorrow (around 90F)

...

Anyway, have not given up on this quest, but it might become just that and a fairly long process...getting the hos guitar operating electronically one these parts arrive regardless of this side of the project likely to be more important at this time

[JohnH]

Your thought about phasing might lead in some interesting directions.

If you invert the phase of each alternate segment, then the bleed into adjacent elements will be out of phase with that from the element itself. So if, in bypassing one to be turned off, you don’t entirely bypass it but do so through a small resistor, a bit of + phase signal will be left to cancel out the small – bleed signals, resulting in overall cancellation. The tricky bit is that when you also turn those others off, the first one will jump back up again. But such an idea could best be configured specifically for just a couple of settings, say all the bass strings on and all the others off, rather than having a free choice of ons and offs.

Just a thought