Making a Stereo (or Hexaphonic) Guitar Pickup

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zebra50

Well-known member
Joined
Jun 4, 2004
Messages
2,943
Location
York, UK
Hi!

Today I made a stereo guitar pickup. I wanted to send alternating strings to separate outputs to spread the frequencies. I wasn't sure what it would sound like, so made this to find out.

Stereo_2.jpg


Here's what I did. I wanted to pick up each string individually so I made six mini-pickups that could be mixed together, and mounted them together in a P90 shape. The component parts were six small bobbins, six pieces of 5mm steel chopped to length, some flat board, and an alnico 5 magnet.

StereoPickup2.jpg


The bobbins were each wound with 5000 turns of 42AWG enamel wire, 3 normal coils and 3 reverse wound.

StereoPickup1.jpg


The hard part was keeping track of the winding direction, the start and end of the wires, and the magnet polarity - so that everything is in phase! Once done, the parts were glued in place, soldered, and then dipped in the wax bath.

Stereo_1.jpg


And then it needs to be mounted in the test guitar - a nice Reverend Slingshot, with the pickup simply taped in place for now.

StereoPickup4.jpg


Each set of three coils were wired in series, and the E,D & B strings sent to one output, and A,G & E sent to the other. One can easily imagine other ways of doing this. Although mine is wired for stereo, one could easily be made into a hexaphonic pickup - although I'm not sure what use that would be in the real world.

So, how does it sound? Here's a little run on the guitar and the screenshot from protools. The recording was made into the instrument input of an API A2D, using the digital output at 24bit, 96KHz into protools. Then no further processing, other than bouncing to 44.1 / 24, and converting to mp3 :(
Excuse my playing but it demonstrates the principle nicely.

ScreenShotProtools.png


...mp3 version...
http://www.xaudia.com/omnip/StereoPickup/StereoGuitar.mp3

As always, the stereo is MUCH better on the .Wav version = 5 mb...
http://www.xaudia.com/omnip/StereoPickup/StereoGuitar.wav

EDIT: There is another clip further down the thread that is a better demonstration

The isolation between the two sets of strings is actually rather good - you can hear & see on the screen shot that the two channels are very very different, following the two sets of strings. It gives a nice interesting stereo spread. The next job is to mount it properly and put a cover on to hide the mess.

I imagine this would be good for double tracked guitars with big Pete Townsend style chords - using two amps!

Stewart

(PS Macbook speakers have almost no stereo separation!)
 
Good stuff Stewart. Weldone.

It certainly gives the feel of dueting guitars.

Leaving six coils individually and having a matrix switch system would offer posibilities. I was not into guitar synth stuff at all but a friend of mine used to play an Ibanez Artist through a Roland in early '80s (copying John Abercrombie).
 
0dbfs said:
That's pretty cool! I can imagine running that with 6 amps would be pretty fun.

Cheers,
j

Man that opens up a lot of cool possibilities! Plus I bet if you sent each pickup to a separate audio --> midi converter it would work much better then a single pickup..

and of course surround sound!
 
Thanks for the comments!

I think I have to give it six outputs now just to satisfy everyone's curiosity. :) I guess I could fit a 7 pin XLR and build a breakout box. More work!

I think commercial midi pickups are hexaphonic anyway, aren't they?

One thing that occurred to me listening to my sound clip is that auto-tuning a guitar would be much easier with separately mic'd strings! :p
 
This sound clip is probably a better demonstration of the effect.

http://www.xaudia.com/omnip/StereoPickup/StereoGuitar2.wav (4 Mb)

And here are the separate channels, for comparison.
http://www.xaudia.com/omnip/StereoPickup/StereoLeft.wav (4 Mb)
http://www.xaudia.com/omnip/StereoPickup/StereoRight.wav (4 Mb)

Cheers!
 
It would be very cool to record that guitar with two amps using a stereo mic'ing technique. 

 
nice idea. My friends brother in law designed a stereo pickup. He tried to describe it to me once and from what he dsecribed was able to split signal in such a way that upstrokes would go out one jack and down strokes out the other jack.

I like this idea. Nice sounding. good on you 8)
 
Thanks guys.

Of course there are no new ideas, particularly in audio. I found this nice little article on polyphonic pickups in Premier Guitar magazine...

http://www.premierguitar.com/Magazine/Issue/2010/Feb/Putting_the_Hex_On_the_Postmodern_Pickups.aspx

:)
 
This certainly rings a bell with me!  In the early 1980's, my long-time friend/client Steve Ripley contacted me about his idea of a stereo guitar (or bass).  I, along with my friend Rick Chinn of Seattle, made various circuit design suggestions, and Steve also went on a crash course of circuit design.  Steve demo'ed his prototype at a NAMM show, and soon made a licensing deal with Kramer.  Steve's design had six panpots...one per string....on the guitar body.  More info here (and also Google "Ripley guitar"):

http://www.vintagekramer.com/ripley.htm

Steve and I go WAY back.  In the 1960's, he fronted a regional band named Steve Ripley and the Innkeepers while I was sort of a tech (hey  I was still in high screwel!) for another band named the Midnight Rebels.  I vaguely recall the Innkeepers and the Rebels playing at a show...perhaps a battle of the bands?  shrug

Circa 1974, I built Steve's first studio in Stillwater, OK.  It had an Ampex AG-440 8 track and a Tascam Model 10.  The FIRST mixing gizmo I built was a custom panel to go along with the Tascam which generated the control room mix, cue mix, etc features which were lacking on the model 10.

Steve ended up in Calif. and worked for Leon Russell.  Later he moved back to Tulsa and  bought Leon's original "church studio".  In 1991, he gutted what had morphed into a MCI room after Leon moved back to Calif, and I installed a "classic" Neve 8068 desk which had originally been owned by the Power Station in NYC.  From that room Steve wrote, played, produced and engineered a multi-platinum album "The Tractors".  Tis the only big time album that I have received a 'mention' in the liner notes <g>.

EDIT:  this was the big hit from the Tractors album....a bunch of great players from Tulsa:

http://www.youtube.com/watch?v=mJKb1BoQ6Ts

More recently, The Church had become a money pit, and Steve sold the place.  The Neve (which he had equipped with flying faders) was sold to Bob Clearmountain.  Steve and his wife relocated to his family's farm property NE of Stillwater where he is slowly building Yet Another studio "complex".  One building there is designated the guitar shop.

Best,

Bri


 
Thanks for sharing that Brian. The Ripley system looks pretty amazing.

I did a bit of further digging into polyphonic pickups, and the earliest that I could find is this patent by James Webster & Gretsch, applied for in 1956. They describe split coils for bass and treble strings, and then go on to describe a system with a pickup for each string.

http://www.google.com/patents/US2964985

So it seems strange that these guys also claim to have invented similar systems in the recent past...

http://www.stereoguitar.com/Investors.html
http://www.google.com/patents/US7982123

I am not sure these would get past a challenge - seem to come under 'obvious' to me.
 
Stewart,

Another thing to know about Jimmy Webster is that he was playing tapping on the guitar when the well known shreders were in their nappies.

I am not sure if you are intending to apply for a patent or there seems to be so many claiming to have patent over it but I would imagine beside Gretsch companies like Roland should have covered it long before. At least have a look at Line 6 Variax.
 
Hi Sahib,

Another thing to know about Jimmy Webster is that he was playing tapping on the guitar when the well known shreders were in their nappies.

I must check him out - I don't know his stuff at all.

I am certainly not claiming an invention! But was curious really to see who first had come up with what seemed like an obvious idea. Gibson have a patent from 1990 that refers to hexaphonic pickups for synth guitars, so it was established technology by then.

I imagine that Fender, Rickenbacher and Gibson must all have experimented with these things in the early days of their pickup winding.

Am amazed that people are claiming to have invented similar things in recent years!

No, I have no intention of applying for a patent, for this or anything else. When I worked at a university research group we used to patent things and it always meant death for the idea. A smart company with money can usually just fine a way around it.
 
And this one is a lot of fun....

http://www.myrareguitars.com/1968-sekova-grecian-electric-guitar

1968-sekova-grecian-electric-guitar-01.jpg


:eek:
 
Check this out. Here are the specs on the Peavey Brian Bromberg signiture model bass. Has pan pots and all kinds of stereo goodies. Who needs them on a bass though? I guess the way he plays yeah you would.

Bass type 4 string fretted
Neck join Bolt-On
Neck construction Modulus Graphite
Fingerboard Phenolic, 24 frets, 34' scale
Body Solid flame maple body
Finish High gloss polyester finish
Pickups Peavey/Bartolini VFL active humbucking PU's
Hardware Wilkinson bridge, Fishman Piezos, Graphlon topnut, Dunlop Straploks
Electronics active 18 volts. Controls front: Master volume, Individual magnetic PU volume, tone network, piezo volume, piezo tone, stereo/mono switch. Controls back: individual piezo level controls, individual piezo pan controls


If you ask me, too many knobs.
 

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pucho812 said:
Check this out. Here are the specs on the Peavey Brian Bromberg signiture model bass. Has pan pots and all kinds of stereo goodies........

............................................
If you ask me, too many knobs.

Agree.

By the time you set your levels the damn gig is finished.

 
Brian,

The 8068 is currently in use at Apogee. They have a studio room where they record, test, etc, etc using the 8068. I tracked on that board last year with a project. nice console in a good sounding room that is very lively.
 
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