Edge: Stage and Studio

Home | * DALLAS SCHOO * | GEAR NEWS | GEAR OVERVIEW - by Era | ACCESSORIES | AMPS // CABINETS | FLOOR EFFECTS // MIDI-CONTROLLERS | GUITARS | RACK EFFECTS | STOMPBOXES | KEYBOARDS | Articles // Features | Icons of Music - 2007 Auction | Icons of Music - 2008 Auction | 'It Might Get Loud' | Music Rising | U2 News | Various Links | Video Links
Brooks - Infinite Guitar


Michael Brook - inventor Infinite Guitar

Michael Brook's Tokai Stratocaster guitar is fitted with an IVL Pitchrider 7000 MkIII pitch-to-MIDI convertor and Digitech Mark IV guitar-to-MIDI interface, triggering a whole battery of MIDI equipment and sample/delay boxes.

The main delays that he uses for looping are the Electro-Harmonix Memoryman and the Bel BD80S delay/sampler. Other equipment that he currently uses for live gigs includes six volume pedals (to adjust the volume of the various loops, plus the level of his infinite and normal guitar output), Eventide H3000 Harmonizer/multi-effects, Electro-Harmonix fuzz, Electro-Harmonix 16-second delay, Yamaha GE10N graphic EQ, Yamaha TX802 FM tone module, Korg OVD-1 overdrive, Sansamp amp simulator, DOD 280 compressor, and a Rocktron Relay Switcher.

The 'infinite guitar' is a famous invention by Michael Brook, that is essentially his superior answer to the E-Bow. It gives the guitarist infinite sustain, with a controllable breaking point where the guitar goes into screaming overtone feedback. Unlike the E-Bow, it does not require the guitarist to hold any devices, and with both hands free great expressiveness can be achieved. Wishing to maintain the mystique, Brook is reluctant to discuss exact technical details, but apparently the infinite guitar works electronically, rather than mechanically, by feeding some of the output of his Tokai Strat back into the guitar.

To date, Brook has made two other copies of his infinite guitar system: one is owned by U2's guitarist The Edge, the other by producer/musician Daniel Lanois.

- Sound On Sound (1995)http://www.soundonsound.com/sos/1995_articles/jul95/michaelbrook.html

More on Brooks Infinite Guitar

Early prototypes:

The first prototype was another pick-up on the other side of the strings so that the two faced each other. His "suitcase" of effects - mostly Electro Harmonix flangers and Memory Mans (Men?) - then processed the signal. Even at this time he was rewiring these pedals and his guitar - this of course with his electronic background lab at A Space.

Technical description of Guitar Wiring and Black Box:

The guitar has an Electromagnetic Transducer in the neck position. The signal from the bridge pickup (Seymour Duncan) is sent through a black box that has a circuit board inside that is an Equalizer that changes the Harmonic structure of the tone of the note(s) played. It boosts and cuts frequencies to make different overtones more or less predominant in the tone of the sustained string. Then the signal goes from the Black Box Back into the guitar and to the Bridge transducer pickup. So basically the signal from one pickup is sent into another pickup making the signal feed back into itself. This creates a feedback loop and the string is constantly vibrating once the transducer begins to move the string by itself by electronically exciting it. (Pulling and letting go of the metal string rapidly and repeatedly. So fast that you can't hear the beats of the pulse.)

Scalloped Fretboard:

The wood between the frets has been removed, forming a concave "valley" between each fret. This modification allows you to get a lot of leverage when it comes to bending (perfect fifth bends become quite easy), allowing for those super-wide sitar style ornamentations. It also allows you to put vibrato on individual notes within a chord. Other notable users of scalloped fretboards include John McLaughlin and Yngwie Malmsteen.

Alan Hoover, of Maniac Music, on the Stealth Plus (Fernandes Sustainer & pickup)

We first made our acoustic type sustainer in 1986 (the Sustainiac Model T, soon followed by the Model B). Then, we heard about the Brook Infinite Guitar when U2 played in Indianapolis in late 1986, as I remember. Edge's guitar tech called us, and allowed us to play a few notes on the instrument after the afternoon sound check. I thought that seemed like a neat way to make sustain, so we designed our own version of such a sustainer after looking at the I.G.

The Infinite Guitar used a regular Duncan stack pickup for a driver. Since this is a high impedance device, it requires around 100 volts of drive signal to produce adequate magnetic drive into the strings. This seemed kind of crazy to me, so shortly after that the Sustainiac GA-1 was born. We made a low-impedance driver so that the sustainer would run efficiently on batteries. The driver could be used as a pickup by attaching a transformer or amplifier to its output in order to increase the voltage output.

The "G" is for Gary Osborne, my partner in Maniac Music. This was followed soon after by the GA-2. We subsequently filed and were granted several patents on our refinements that allowed the magnetic sustainer to be used as a practical, manufacturable device. We never attempted to patent any of the basic principles, such as a pickup being used in reverse to drive the strings, because we always felt that that credit belonged to Michael Brook.

Curiously, Michael (whom I met and talked to at length in 1990) never followed up with his British patent that he filed sometime around the 1985 timeframe. Typically, patent offices reject first applications over technicalities. It is up to the inventor to persist and argue his/her case. Michael gave up and didn't argue his case, so he never got a patent. He told me in conversation that he was very busy, and also really didn't know that you could present an argument and maybe get your patent.

Then, Floyd Rose et al got a U.S. patent on a magnetic sustainer driver in 1990. Curiously, they claim never to have heard of the Brook device prior to making their sustainer. I know of no facts to contradict this. We have a patent cross-licensing agreement with them.

We sold several thousand of our Sustainiac GA-2 sustainers to Fernandes around 1990. I personally trained several Fernandes personnel in the operation and installation of the GA-2. Soon after that, the company that was manufacturing and distributing the Sustainiac GA-2 for us (Audio Sound International, of Indianapolis, IN) went out of business.

When ASI went out of business, Maniac Music didn't do much with sustainers for several years. In 1999 we came out with the Sustainiac Stealth sustainer to solve the retrofit problem that had always faced us with the Sustainiac GA-1 and later GA-2 sustainers. (People are reluctant to route large cavities into their guitars.) Then early this year, we started selling the new Stealth Plus sustainer.

These are proving to be successful sustainers for the retrofit of existing instruments. They have the advantage that for most installations, no permanent change needs to be made to the instrument, so that a vintage instrument can be restored back to its original condition should it be desired. Furthermore, the bilateral driver (our U.S. Patent number 5,932,827) allows almost complete cancellation of the driver's radiated magnetic field that is sensed by the pickup. Consequently, for the first time, single-coil pickups can now be used to supply the input signal to the sustainer.

You can find out more about the Sustainiac products from our website: www.sustainiac.com