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Bluetooth device? Answered

Hi, I have a device connected to my guitar that sends information to another device by a 13 separate PINS cable, I would like them to comunicate with Bluetooth or any other wireless device, arduito etc. how can I do that?  where should I begin my research?

thank you!

Daniel Cuartas


what kind of data is it?  Digital? Analog?  how much data is it?  If it's too much, then typical wireless solutions might not be able to handle it.

A good keyterm is "module"
like bluetooth module
or wireless module
or rf module
also, if the guitar is only sending data, you should just get a transmitter for it, not a transiever (transmitter and reciever) to save money.

I don't know what kind of data is, I think is analog, don't think it would be a lot of data. and it would have to be a transiever.

this is the device:

it's a special pick-up that converts the strings sound to a midi sound, and besides that, it takes the normal signal of the guitar and two buttons and one knob placed in the device.

I don't know if this could be useful:

Roland 13 pin system:

This carries six individual signals from the hex transducer AND a single audio feed from the guitar's normal electrics.

If you add a GK pickup there is a flying lead which plugs into your normal guitar jack.

Pinouts & wiring colours, 13 pin DIN cable

Pinouts for the 13 pin DIN connector used with the Roland VG8, VG-88, GR1, GR9, GR20, GR30, GR33, GR50, GI10, GI20, GKP-4, Boss DC-20G, WP-20G, Roland Ready Strat, Axon AX100, Yamaha G50, G1-D, Ibanez RG470GK, Brian Moore Guitars + lots of others.

The Roland cables are good quality 13 core, with a braided copper screen

The pins, signals and wire colours are as follows:

1 -   String 1 - Brown
2 -   String 2 - Blue
3 -   String 3 - Grey
4 -   String 4 - Orange
5 -   String 5 - Pink
6 -   String 6 - Purple
7 -   Normal pickups - Green
8 -   MIDI volume - Yellow / Stripe
9 -   Unused - Yellow
10 -  Switch 1 - Red
11 -  Switch 2 - White / Stripe
12 -  +ve supply - White
13 -  -ve supply - Black

These were taken from a Roland cable manufactured in 1998.


Since the advent of MIDI (Musical Instrument Digital Interface) us guitarists have wanted to be in on the act. Why should keyboard players have all the fun?

The main obstacle to MIDI on guitar has been the way the MIDI signal is generated. On a keyboard it is simple, you press the key, you generate a "note on" signal, you release the key and you generate a "note off" signal.

What a MIDI generator for guitar has to do is quite complex, first it has to detect that a note is being played, then convert the pitch of the note so this information can be sent as a "note on" signal. As the note decays there is a point where the MIDI generator has to decide to send a "note off" signal. In addition, if the guitarist bends a note, the appropriate MIDI pitch bend signal has to be sent.

Now if this process didn't seem quite complex already, there is a hitch. You can only do this with one note at a time, more than one note would totally confuse the pitch to MIDI convertor. So the solution is simple, use a MIDI convertor for each individual string. At this point conventional guitar pickups go out of the window, they do six strings at a time. What you need is a pickup with six individual outputs, one for each string, what we call in the trade a "hex" pickup. (I think hex is Latin for six)

The output from commercially available hex pickups is quite low, so they all have a small pre-amp circuit located close to the pickup. In the case of the Roland hex pickup this is either a GK2A or GK3A, and for RMC equipped guitars (Godin, Brian Moore etc.) it is a small pre-amp board located inside the guitar.

What most of these controllers offer via a single 13 pin connector is six individual string outputs, a master output - either a mix of the six strings or a through signal from the guitars normal electronics, a MIDI volume signal - via a volume control, and two control switches - usually up/down patch selection.

Even though these hex style pickups are intended for MIDI implementation, there are now products that use the six individual string outputs to implement guitar modelling and the individual processing of single strings for effects such as harmonists and instant alternate tuning. The Roland VG88 and its predecessor the VG8 being the best known.

What has actually been handed to us guitarists is very interesting, yes we have MIDI, yes we have modelling, but we also have a system giving us signals from each string individually. Imagine taking each string through a different effects box, or sending alternate strings to different sides of the stage. Or setting up drone strings to improvise over?

There are two ways of doing this, you can purchase the RMC fanout box a fine unit but priced at $395 US. That's quite hefty if you have to pay post, packing and duty to Europe. Second method is you can build your own. Not too difficult as we will be building one ourselves over the next few days. Check out Unfretted's hexaphonic break out box and keep coming back for sporadic updates. We will be including all the info to build a custom job to your own specification.