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How to connect a keyboard to miniBRUTE DRSSTC kit?

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LAN_403

nobredab

Sat Mar 31 2007, 10:25AM

Registered Member #620 Joined: Sat Mar 31 2007, 09:55AM
Location: Berlin
Posts: 1

Iâ€™m think about to order the new miniBRUTE DRSSTC Board Kits from EastVoltResearch, but it is very important to me to have a possibility to connect a standart (music) keyboard to this coil. Can somebody tell me how to connect it or maybe a way to modificate the Advanced Modulator Board? Thanks for any helpful posts!

ragnar

Sat Mar 31 2007, 10:48AM

Registered Member #63 Joined: Thu Feb 09 2006, 06:18AM
Location:
Posts: 1425

I would like to help; I've connected my keyboard to a TC (though not with a DRSSTC) -- but I feel, however, that it's a slight infringement of the work of SteveC and FinnH who pioneered the idea.

I think I'll let Steve or Finn offer their advice, if they wish to.

Finn Hammer

Sat Mar 31 2007, 11:23AM

Registered Member #205 Joined: Sat Feb 18 2006, 11:59AM
Location: SkÃ¸rping, Denmark
Posts: 741

BlackPlasma wrote ...

-- but I feel, however, that it's a slight infringement of the work of SteveC and FinnH who pioneered the idea.

I think I'll let Steve or Finn offer their advice, if they wish to.

Thanks, BP.
I will go, and have gone to great lengths to help others in coiling, except when it comes to connecting it to a keyboard.
Do that and you are on your own.
I have 6 DRSSTC`s that connect to a Stephen Conner modified keyboard, and that special gimmick, I`d like to have exclusive rights to as long as I can.

Cheers, Finn Hammer

HV Enthusiast

Sat Mar 31 2007, 03:20PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

wrote ...

Thanks, BP.
I will go, and have gone to great lengths to help others in coiling, except when it comes to connecting it to a keyboard.
Do that and you are on your own.

In all fairness, I believe this individual is only looking for a simple method (not a MIDI based method) of connecting a keyboard to the DRSSTC. I think he is looking into what Steve Ward did way back when by simply outputting a simple sine wave on the keyboard and then using a zero crossing detector to generate a pulse waveform.

So basically thats it. I think the flute sound on a keyboard will give out a sine waveform, and then you can just pass this through a zero crossing detector (or similar) and convert to a pulse which can then trigger the interrupter at the audio frequency. Quite simple and done with a handful of parts.

If you do want to go the MIDI route, someone on the geekgroup has a website showing how he did this complete with schematics.

wrote ...

but I feel, however, that it's a slight infringement of the work of SteveC and FinnH who pioneered the idea.

The infringement would have to be regarding the MIDI implementation of a keyboard controlled DRSSTC. People have hooked up keyboards to SSTCs and DRSSTCs long before their work. (Steve Ward hooked keyboard up to his DRSSTC, and there were others as well)

Again, this guy i believe is looking for a very simple implementation, not a MIDI based implementation.

Steve Ward

Sat Mar 31 2007, 10:08PM

Registered Member #146 Joined: Sun Feb 12 2006, 04:21AM
Location: Austin Tx
Posts: 1055

Yep, there are a few common ways of interfacing a keyboard with a DRSSTC. I certainly cant hold it against Finn for not releasing all the details on his control scheme, though id be curious. Even if i did know, im just too stubborn, and will go with my own method anyway.

My next controller will implement both an analog audio input, as well as a MIDI input. When its all done and working, i will release the details. You will have to be familiar with micro-controllers (AVR in particular) if you want to copy this design. Of course, i might be tempted to sell a few of them, but they wont be cheap.

One of the biggest problems with using the keyboard is that the DRSSTC will put noise back into it. My simple controller had this problem, likely because 1) no isolation between the keyboard and DRSSTC controller (an optocoupler or fiber optic cable would have helped!), and 2) my keyboard was a cheap plastic thing, so it was completely vulnerable to EMI. So my zero cross scheme worked "most" of the time, but would mess up often, many times depending on the location of where i was running the coil.

teravolt

Sun Apr 01 2007, 04:17AM

Registered Member #195 Joined: Fri Feb 17 2006, 08:27PM
Location: Berkeley, ca.
Posts: 1111

A standard wave form such as music has two parts frequency and amplitude that vary. I have thought how to do this and frequency can be controled by squaring the audio and feeding it in to the interuptor in put and amplitude could be controled by varing deadtime. combining this is tricky and I think it is puasible. what do you think

Mike

Wed Apr 04 2007, 06:00PM

Registered Member #58 Joined: Thu Feb 09 2006, 05:40AM
Location: Tri-Cities, Washington, US
Posts: 317

Smlizz showed me the way he has done this quite simply.

The two schems can be found

It is basically as described as above. A audio sine wave is converted to a squarewave, sent to a FOD2200 optoisolater, and then sent to the ucc enable pins.

I have heard that this method, along with some other midi control electronics is how finn's coil works but i may be wrong. guess we'll never know :P

HV Enthusiast

Wed Apr 04 2007, 08:36PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

The MIDI implementation, should you decide to go that route, is quite simple. In fact, if you do a search on GOOGLE, there are tons of websites that are devoted to MIDI decoding and output control and thats probably enough assuming you aren't already familiar with MIDI interfacing.

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