The idea is to build an Infinity Sustainer for my guitar, this is basically an E-Bow type device fitted into the body near the neck that excites all six strings. This is not a new idea, it was mentioned in E-Bow's original patent application and Fernandez and Kramer built several guitars with built-in sustainers, but they are expensive.
 

Since this project involves modifying the guitar (and I don't know whether it will work yet) I am going to be making these mods to a cheap Fender Squier.

 

The principal is simple: sound from the pickups is amplified and used to drive a coil that excites the strings. I intend to wind my own driver coil for this based around a bare Fender-style pick-up bobbin:

 

 

This will be wound with heavier gauge wire than a normal pickup, and with fewer turns to give a lower impedance -  the idea is to make the equivalent of the voice-coil in a loudspeaker, therefore the impedance should be around http://pickups.myonlinesite.com/pickup.php?unit=mm&cl=55&cw=5&ch=3&bw=16&bt=1&ends=round&wd=0.2&id=0.23&show=on&avt=100&adj=ohms&avo=8 - 8ohms  so I can drive it from a 1W amplifier that can be powered from a 9v PP3 battery:

 

 

...which may not have enough gain on its own, so I'll probably need a FET i/p stage for it.

 

 

Initially I will use this pickup in place of the neck pickup - once I've got it working I'll consider putting the neck pickup back and routing a new hole in the body for the sustainer. Even though it's only a £150 Squier, I'm still loathed to attack it with power tools just yet

 

 

So, the story so far: I've worked out pretty much what I want to do, ordered the pickup kit from Stewart-MacDonald and the electronics from Maplin - just waiting for the postman now.

http://www.stewmac.com/shop/Electronics,_pickups/Pickups:_Kits/1/Parts_Kit_for_Tele_Neck_Pickup/Pictures.html#details -  

 

 

I guess you haven't used a sustainer pickup before (probably cos you play bass), but a friend of mine has one on his Jackson DK2S Pro series guitar, specifically using the Sustainiac brand.

It has 3 modes.

One allows you sustain the 'fundamental' note, the actual note you play.

The second is called Blend, which harmonics and fundamental certain notes.

The 3rd is called Harmonic, which depending on what brand of sustainer you use, makes the fundamental note swell into a 5th or octave above the fundamental note. It sounds exactly like feedback in most cases, bearing in mind I'm talking about the musical type of feedback you get from a fundamental note swelling into a feedback harmonic, as opposed to the feedback generated from noisy preamps/excessively long pedal chain which sound harsh.

There is also a control, on the Sustainiac version at least, called Intensity Control, which controls how fast the notes swell into sustained notes/feedback.

 

Now that you have some background in it's functions, I'll answer your question more specifically.

If you were referring to 'feedbacking like mad' as the unmusical and harsh feedback caused by noisy preamps and excessively long pedal chains that problem is tackled by noise gates/noise reducing pedal. Noise Gates/Reducers can also to some extent reduce the chances of the musical type of feedback, because most, if not all Noise gates/reducers tend to cut off a bit of the tail end of notes, reducing a notes potential sustain.

By using the fundamental mode, the note you choose to hold will not swell into a harmonic feedback, as the note you are holding will stay as the fundamental.

Obviously feedback is not easy to get at low amp volumes, so some people love the sustainiac, because it allows them to create musical feedback at low volumes, and it can even allow you to create great sounding feedback on the clean settings of your amp.

 

Another question that was raised was about dampening notes. Since the sustainer driver doesn't really sound effective with more than one note at a time, you have to mute the other strings, but assuming you've learnt to play guitar properly in the first place, you would have already learnt how to mute strings that you don't want to ring out anyway, using left hand or right hand techniques, or a combination of both, depending what string you are on, what you are playing etc etc.

If you try to play 6 note chords, but some strings 'win out' and keep sustaining, which from first hand experience, will be the lower, heavier strings.

You can do some cool stuff on a clean amp setting, using finger style and playing arpeggiated chords, and getting some cool sounds with the sustainer, but once you pile on the gain, typically you will only sound good using single notes, and with this much gain, the sustainer driver only really works effectively with one note at a time anyway.

 

Hopefully this answers a lot of questions anyone may have had about the sustainer driver pickups.

the open strings are undamped - they well hum at a harmonic of the excitation note(s) - I haven't seen a bought system that damps individual strings - obviously palm and finger muting is the key to controlling any unwanted sympathetic vibrations.

 

I'm not familiar with any of the existing sustainer devices such as the Sustainiac (they have stopped producing the electromagnetic version) - I imaging the different modes of operation are just varying degrees of gain and phase shift (filtering) which can be controlled by internal feedback around the drive amp, though the possibilities for electrical manipulation of this feedback signal are endless and only limited by how much electronics you can fit into the body cavity - again, this is an area for experimentation and another reason for doing this to a cheap guitar first.

 

As I explained my last post on this thread, using the fundamental mode will ensure the note continues to sustain purely as the fundamental note. An ebow and sustainer driver pickup really aren't the same beast.

I have been using the Sustainiac pickup fitted to my friend's Jackson DK2S Pro Series guitar since he got his guitar in May last year, and you can seriously sustain a note as long as you want without it swelling into a feedback harmonic.

 

The Sustainiac replaces the Middle Pickup with the Driver Coil, which is also used as a normal pickup when the Sustainer circuit is switched off - since this pickup has fewer turns than a standard pickup it produces a smaller signal, so a built-in pre-amp is used to match the amplitude to the other two pickups.

 

The Fundamental Mode is essentially feedback from the Neck Pickup fed through a wide-band filter, 480Hz to 3400Hz, (which is something like A#5 to G7). The signal from this pick up generally contains more of the fundamental and less harmonic frequencies, so when used to provide the excitation frequencies to the Driver Coil it will tend to vibrate the strings predominantly at the fundamental note.

 

Harmonic Mode is feedback from Bridge Pickup fed through a narrow-band filter centred on 720Hz (somewhere around F5).  The signal from this pickup is rich in harmonics and so when fed to the Driver Coil will favour harmonic resonance.

 

Obviously "Blend" is a mix of the two and when the Sustain circuit is switched on, the middle pickup cannot be used as a source.

 

Both the Neck and Bridge filters remove the extremely high harmonics that would result in (electrical) instability.

 

The low-frequency cut-off for both is two octaves higher than the lowest note a guitar can produce and I'm not sure quite why that is at the moment so I will have to investigate this further once I start building, but I suspect it is because the lower notes require less energy to make them sustain.

 

 

Actually, My friend's Jackson is actually really good value for money, not actually an expensive guitar at all, but I compare to the Fernandes guitars, as I'm pretty sure you can't get them here in Australia and I believe the Kramer guitars fitted with Sustainers are out of production.

 

 

 

Actually I think it would fit in really well with my band's sound.  I play bass with an ebow a lot.

 

Anyway, instead of worrying about damping the strings, maybe alternate tunings could produce some sweet chords.

Also, will this gizmo have an on/off switch or will it be a full time thing?  If I were building it, I'd drill a hole for a small toggle switch.  Speaking of which, is this sustainer pickup system active?  Also, a bright blue LED is the crucial (and cheap) addition to any DIY project.

The Fernadez website has a demo using chords, I don't see any reason why this can't play chords too.

 

However, on reflection, it would be better with a hex-pickup (like a MIDI pickup) and hex-driver, (i.e. 1 sustainer per string), but that's also 6 times the electronics which would reduce battery life. Also, I'd rather get this version working first

 

GoldenSpiral wrote: Also, will this gizmo have an on/off switch or will it be a full time thing?  If I were building it, I'd drill a hole for a small toggle switch.

I've bought a volume pot with a built-in on/off switch.

GoldenSpiral wrote: Speaking of which, is this sustainer pickup system active?

  

It can be, but not in this version - it has a pre-amp for the pickups but it is bandwidth limited so wouldn't be much use - the O/P jack bypasses the pre-amp.

 

It is something to think about in the future, but since I'm keeping the standard Squier pickups, their o/p doesn't call for an active drive.

GoldenSpiral wrote: Also, a bright blue LED is the crucial (and cheap) addition to any DIY project.

-------------
What?

Found a source of small neodymium magnets so ordered some to play with - unfortunately from Germany (this is turning into quite a transcontinental project) so they haven't arrived either.

 

Found a huge ceramic bar magnet at home and wound a small coil around it so I could test the electronics:

 

 

I haven't opened up the guitar yet, so I am using an Alesis NanoCompressor (in bypass mode) to split the output from the guitar jack in two - one side to the practice amp the other to the sustainer circuit. The chromatic guitar tuner above is just a double check that it is the guitar that is sustaining and not just the circuit oscillating. The circuit board with the amber LED is the drive amp, the other is a small pre-amp/filter. I can make the LED burn a bit brighter by using a transistor to switch it, but that is way down the "to do" list.

 

Well, it works. Not great, but at least it makes some kind of effect. The bar-magnet is far to powerful and messes with the pickups if you hold it too close to them, but holding it near the strings at Fret-12 seems okay (but not practical). I guess I'm going to have to wait for the postman now...

 

 

It has the same features as the Sustainiac brand sustainer driver it seems.

My guess is that when it is used as a neck pickup alone, it sounds different to the Sustainiac pickup in the neck, but from what I've read, they aren't that much different sounding when used as a stand alone pickup.

A lot of people have been asking over the years 'can I put it in the middle position instead? I really like the sound of my neck pickup and want to leave it that way'. The answer is, you simply can't put anywhere else except for the neck position.

The sustainer driver needs to be as far as possible from the pickup.

It's just like, putting a microphone too close to the speaker of a PA, it feedbacks, and of course just like putting a pickup (a microphone) too close to the amp speakers.

Another reason it needs to be in the neck, is because the harmonic mode will produce the best harmonics in the neck position.

I've read the three main patents (EBow, Floyd-Rose & Mainiac) and I've browsed the Guitar Project forum. But, No, I haven't actually used one (that obvious huh?) - and I cannot afford one either, that's why I'm doing a scratch build  

 

(I have used an E-Bow, but don't own one.)

HughesJB4 wrote: There is a reason why it goes in the neck pickup, and not the middle or bridge. A lot of people have been asking over the years 'can I put it in the middle position instead? I really like the sound of my neck pickup and want to leave it that way'. The answer is, you simply can't put anywhere else except for the neck position.

In my original post I said I was putting the driver in place of the neck pickup - I don't plan on changing that, but I am intending to build a thin driver that I can try in different positions to find the optimum position for myself rather than blindly follow what everyone else does.

 

My comment about the middle position fitting was based upon the patent: the original Sustainiac patent has the driver in the middle position, even though in all production units they are fitted in the neck position. I would imagine that the prototype units were fitted in the mid position and worked adequately enough for them to think they could take out a patent for their invention. I also suspect that the Sustianiac designers found it was more efficient at the neck position after the event.

 

(I also suspect they had to make the patent substantially different from the Floyd-Rose design for it to be granted).

 

... but then the patent is shot full of (deliberate?) errors so I would not recommend copying the design from it - it simply won't work.

And BTW, a lof of that info I got, was from the actual Sustainiac website. Although I understand the sustainer driver will probably still work in the middle position, if it really were effective in that position I don't think Sustainiac would have strongly recommended it be used in the neck position.

Not sure about this one, but I imagine it being in the middle position combined with high gain would squeal like a dying pig. It doesn't make matter's any better that you use single coil pickups either (unless of course you plan to switch to a noiseless single coil or put a noise gate in the effects loop and one before after the preamp). But then again, if I were playing high gain, I wouldn't be using squier single coils anyway

 

I did make a full-width low-profile driver-coil but made it too thick to slide between the scratch-plate and the strings (which kind of defeats the object of making it ) - I  could try it on my daughters LP copy as there is enough height between the body and the strings for that, but I don't think I'll be able to get it far enough away from the bridge humbucker to prevent cross-talk. However, it might be a good way to experiment with shunt plates to control the electrostatic feedback and to play with phase-shifting the signals. I also want to use this coil to experiment with driving it from another instrument (such as a keyboard or a theremin) so the guitar will respond with sympathetic vibrations (left-hand fretting the guitar, right-hand on the keyboard...). I also want to try this driver on my Long Thin Wire installation, ( http://members.aol.com/CacophonyOfLight/instruments1.html - http://members.aol.com/CacophonyOfLight/instruments1.html ).

 

I've also started building a Class-D drive amp for the diver coil - this has several advantages over a standard Class A/B amp - least of which is that it can drive the LED to full brightness  - at the moment I have all the semiconductors and resistors needed, but cannot find enough suitable capacitors in my spare components to complete it. Moving the signal into the digital domain opens up a whole world of DSP possibilities, but that's for another day.

 

 

http://www.projectguitar.com/tut/sustainer.htm - http://www.projectguitar.com/tut/sustainer.htm

 

I'm only posting this hoping this could help. This sounds like a great project that I might attempt myself when I have a bit of time this summer.

Looks interesting Darren.

 

it works on a different principle to the one I'm building - the feedback is acoustic through the piezo speaker rather than electromagnetic through the coil, which is closer to the feedback you get between guitar and amp, but less controllable. The peizo speaker has a dreadful frequency response (they are often used as tweeters in cheap two-way hi-fi speakers) which is why the circuit doesn't need any filtering making it a lot simpler than mine. I have some of those lying around somewhere from an earlier project (sensors in an electronic drum-kit) and they use them as keyboard bleepers in some PCs, so if I can find one I'll give it a try. Unless I am missing something (like capacitive coupling between sounder and pickup) I don't see why they've glued the sounder to the pickup - I would imagine that it can be placed anywhere near the strings.

Here is the 1st attempt at the proper driver/pickup

 

The top section (above the white spacer) is the driver coil - 130 turns of 28awg giving about 8.5 ohms dc resistance - a bit high but it's easier to take some off than to put more on. The bottom section will become the normal neck pickup coil when the sustainer is not being used - and that is as many turns of 43awg as I could get on the bobbin - it comes out at 4.7Kohms dc resistance, which means the output will be about 60% of a standard pickup, but the driver electronics could be modified to make an active pick-up circuit when not in use if needed. The magnets are polarised south-up and the coils wound clockwise to match the original pickup, so hopefully the phase of the signals will be the same as before.

 

 

I haven't potted it yet as I've not finished the evaluation, so I have no doubts that it will be highly microphonic until then, but that's not a major issue at the moment.

 

I have made a Class-D amp to drive the driver- there is a lot of HF break-through (of the PWM clock) at the moment because the circuit is built on patch-board and not a neatly art-worked pcb, but this can be cured easily enough. The real problem is that it is physically larger than the first amp I used, which may be more of a problem. I had worked out how to remove a small amount of wood from the body between the pick-ups to fit the old amp electronics, but it won't fit this new one - I was also hoping that I could fit the battery into the trem-spring well on the back of the guitar, if not then I'm going to have to make the hole under the scratch-plate bigger anyway.

 

Having decided to mod the Squier, I've invested (very little cash) in a new EMG twin-coil bridge pick-up to replace the original Chinese single-coil one. On first listen the tone is softer than the original and the output lower - not sure whether that's a good thing or a bad thing yet, (it's not a Strat any more - then it wasn't really one before either), but it certainly looks nicer

It's finished  - well Mk-1 version is

 

Since I was taking the guitar to pieces I thought I'd re-vamp it a little at the same time. I've improved the screening of the guitar to reduce noise and stray interference by lining the cavity and pick-guard with foil. I've upgraded the middle and bridge pickups to twin-rail units by EMG, fitted black pick-guard, trem-cover, jack-plate and strap-locks... budget didn't run to upgrading the trem-unit or tuners for black jobbies, but one day...

 

Here's the new pick-guard with the two EMG Select pickups, the new neck pickup/sustain driver and all the electronics - the back-side of the pick-guard has been covered with aluminium cooking-foil glued on with spray-mount - I've cut strips of foil away between the pickups to reduce induction-loops that would load the coils:

The old volume control is now the sustain drive control and the volume pot is now the one near the middle pickup. This is to allow me to tweak the volume using my pinkie finger while playing to make 'violin' swells. The two extra switches switch on the sustain and switch the phase of the driver-coil. The coil phase determines whether the sustain is on the fundamental note or the harmonic. The LED (near the neck pickup) is dual-colour - the blue side shows battery power and the red side is the sustain signal.

 

This is the copper-screening in the enlarged body cavity. The routed cavity looks huge here, but very little wood was removed, just the 'land' between the neck and middle pickup and and widened the area around the selector switch to make room for the new pot.

 

 

The battery-box fits just behind the new trem-cover, the two wires from the battery go through a small hole drilled through the battery cavity into the jack cavity, where the earth-lead is switched by the jack-socket:

 

And here is the finished guitar:

Seeing it here I think I will upgrade the trem-unit soon, simply because I think the chrome spoils the overall effect - I know that's cosmetic but then a replacement Wilkinson/Gotoh has to be an improvement on the original one. The only down-side is that Stewmac won't ship black units to the EU. I could order these from Axesrus.com, but I am a tad reticent as neither the pick-guard nor the trem-cover fitted my guitar and I had to drill new holes for them - I'm not criticising Axesrus here - my guitar is a Fender Squier, not an original Strat so the fittings may be different and with a 6-hole baseplate that's a lot of re-drilling

 

So... how does it play?

 

Very nicely

 

With the sustain switched off the new pickups are amazingly good compared to the Chinese originals - they are almost as bright with a slightly warmer tone, which I actually prefer. The home-made neck pickup works surprisingly well, with the reduced number of turns matching the EMG output  - it also has a warmer tone compared to the original pickup. Overall the noise is significantly reduced and there is zero hum, buzz or fizz from mains interference.

 

However, the bottom-line is that it is still a Squier - even though the body wood was better quality than I imagined, it's natural tone is still a little dull.

 

With the sustain switched on things get a little difficult to control - drive levels are hyper-sensitive and palm & finger muting of unwanted strings is essential - but it works - notes can be held indefinitely, which is the basic idea . The only problem at the moment is that some strings and notes sustain better than others - this is a question of pre-amp filtering which I still need to do some more experimenting with. When I get confident enough in using it I'll upload some audio samples.

 

For those interested in the electronics, the circuit schematic is here: http://i198.photobucket.com/albums/aa289/darqdean/guitar1.gif - http://i198.photobucket.com/albums/aa289/darqdean/guitar1.gif

 

EDIT:, BTW, Looks like you did a really good job!

And you don't even get the fun of the awesome dive bomb range of a locking trem with a 6 point trem or even the 2 point knife edge trem, which takes a bit of the fun out of it too .

I can understand you not wanting to do the sustainiac with the Kramer though, Kramer has made some pretty darn nice guitars, which is probably the reason you can get super strats with sustainers put in at the factory.