The GM Voice

Thomas Henry · Posted: Wed Nov 14, 2007 9:23 pm Post subject:

I've attached the front panel design I used, in case anyone wants to duplicate or modify it. It's in MS Word format. I printed it in color on full sheet sticky-back material, laminated with a full sheet clear sticky-back, and slapped it on to the aluminum panel which fits on the front of a plastic box.

I'm continuing to find new things in this project; it really is one of the more rewarding things I've ever built for the studio. Tomorrow a full 88 key, velocity sending, semi-weighted keyboard arrives and then I'll go to town! Total cost is:

$10 for the daughterboard
$15 for auxiliary parts
$200 for full 88 key MIDI keyboard

For a total of $225 I will have a complete 24 note polyphonic synth with over 200 patches!

Wow! Why did I wait so long?

Thomas Henry

GM Voice Panel.doc

Description:

Color, front panel design, in MS Word format.

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GM Voice Panel.doc

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Thomas Henry · Posted: Thu Nov 15, 2007 10:37 pm Post subject:

Wow! Am I sailing now!

My new keyboard arrived today. It's a full-sized M-Audio, 88 key, semi-weighted, velocity sending unit, with all sorts of MIDI buttons and wheel controls. I only paid $200 postpaid for the thing, new.

I immediately patched it to the GM Voice and have been in seventh heaven all night.

I'm quite sure my inadequate words haven't conveyed what this project represents. So, you'll just have to take it from me that is the acme of any synth project I've ever been involved in. I wish I had done it ten years ago when Antman first proposed it---my recordings would have been far more advanced early on.

By the way, I haven't been able to get reverb or chorus either, and for that matter portamento hasn't appeared either.

But I can do pan, vibrato and volume okay.

More to come, later---this project just keeps a-growing...

Thomas Henry

Scott Stites · Posted: Fri Nov 16, 2007 4:11 pm Post subject:

So, you can access all of the voices from the keyboard, then?
How many notes polyphony can you get?

My, my....

Thomas Henry · Posted: Fri Nov 16, 2007 4:35 pm Post subject:

Scott Stites · Posted: Fri Nov 16, 2007 7:40 pm Post subject:

I dunno, ten bucks...that's a lot of dosh Very Happy

I've been dreaming of buying an inexpensive digital synth to use as a MIDI controller, and give me some built-in polyphony, too. One of those mini Korg thingies with the tiny keys (tiny keys don't bother me, after what I'm using now, Schroeder's piano would be like playing a Steinway). They're, what, $300 or $400 bucks or something like that. Or, a little more money would get one of those Roland SH-201s. Can you tell I'm really up on commericial synths? Laughing

My DW6000 has MIDI, and I've controlled the Roland Sound Canvas with it before, but the DW6K didn't seem to have any way to access all of the voices on the SC.

Thomas Henry · Posted: Sun Nov 25, 2007 9:18 pm Post subject:

Well, I've spent the past couple of weeks recording a new song with the GM Voice, and let me tell you, this has really changed how I approach things now. Hands-down, this is the most useful music circuit in my system.

I thought I would mention that the reset button is actually pretty handy. The GM Voice so far has worked flawlessly. But user error (me) occasionally will interrupt the Cakewalk sequencer at an awkward moment. This might leave the GM Voice wondering what volume it should be at. (Last night, for example, I interrupted Cakewalk after it had turned the bass guitar volume down---of course, when I resumed, no bass could be heard).

Anyway, a quick punch of the button and we're back in business. It makes an excellent "get back to normal" feature, requiring no thought.

Thomas Henry

fonik · Posted: Mon Nov 26, 2007 5:53 am Post subject:

i just got a db50XG so i will join the club soon. i wonder how to add an mono output: just mixing both channels? or should i add some phaseshifting to one channel before mixing to eliminate possible cancelation of the signals?

Thomas Henry · Posted: Mon Nov 26, 2007 5:58 pm Post subject:

Good job, Fonik. I think you'll get a real kick out of this circuit.

Actually, the circuit already has two mono outputs (and one stereo output if you'd prefer to use it instead), so you won't have to change anything. Just send a MIDI controller pan to the GM Voice.

For example, if you want a mono trumpet output, just send the MIDI message to pan it all the way to the left and use that output jack.

As a bonus, you can MIDI pan another sound (a saxophone, say) all the way to the right, thus getting two independent voices on separate outputs, perfect for shooting straight to a mixer.

Anyway, you shouldn't have to change anything. And if it isn't clear, you can just leave the stereo jack out if you never do stereo things. A person would never use the two mono outputs and the stereo output at the same time, anyway.

Now, as promised, attached is an instrument definition file that will save everyone some typing. You use this with MIDI-Ox, a superior piece of free software, to easily control the GM Voice from a computer. It gives you easy access to the two-hundred some sounds inside the unit.

I adapted this file from one used with old versions of Cakewalk. It's an ordinary text file, so you can feel free to load it up in a text editor and modify it as desired (like I did). When you're ready to use it with MIDI-Ox, rename it with a .ins extension. This stands for instrument definition file, obviously. Store it in the INS directory within MIDI-Ox.

That's it for the downloads. Everything should be in place for anyone desiring to build this creature: schems, PCB artwork, front panel graphics, pics and the instrument definition file.

Thomas Henry

Instruments.txt

Description:

Instrument Definition File for the GM Voice.
This is an ordinary text file. Rename it to "Instruments.ins" before using with MIDI-Ox.

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Instruments.txt

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Thomas Henry · Posted: Thu Nov 29, 2007 9:41 pm Post subject:

I'm currently dinking around with another daughterboard, trying to make it do some neat stuff in an old, unused 486 machine. I ran across this great article tonight which shows some mods that might be useful to anyone playing with daughterboards.

http://www.soundonsound.com/sos/1997_articles/feb97/soundcards.html

One of the fun aspects of playing with these is searching for Easter eggs...you never know what you're going to find. So it's back to the basement to look for more myself...

Thomas Henry

Dan Lavin · Posted: Fri Dec 14, 2007 9:33 pm Post subject:

If anyone is interested in a db50XG Yamaha board, and are willing to risk an ebay sale from Shanghai (please spare me the jokes), you can try:

link

A little rich for me after shipping, but I'm not exactly known as someone who's loose with their cash!

[Blue Hell: shortened the link]

State Machine · Posted: Sat Dec 15, 2007 11:26 am Post subject:

For anyone interested, here is a link for the Yamaha DB50XG manual. This is the unit being sold on Ebay that Antman is talking about.

http://www.usersmanualguide.com/yamaha_audio/computer_peripheral_devices/db50xg

Bill

fonik · Posted: Sat Dec 15, 2007 12:55 pm Post subject:

i bought one 2 weeks ago. the specs are impressive. i just etched me a motherboard with thomas' circuit to carry the db50xg and to add it to my modular...

BTW did anyone measure the current the GM needs?

Thomas Henry · Posted: Sat Dec 15, 2007 2:07 pm Post subject:

On my unit +12V was at about 80mA (of which around half is due to the +5V regulator it drives). -12V was at virtually nothing.

One could use a 79L12 for the negative regulator, but the others should probably be 7812 and 7805 to avoid the need for heat sinks.

Thomas Henry

Scott Stites · Posted: Sat Dec 15, 2007 2:34 pm Post subject:

Antman Dan just enabled me to go down this road. This looks like a lotta fun!

fonik · Posted: Sat Dec 15, 2007 3:34 pm Post subject:

RF · Posted: Sat Dec 15, 2007 3:57 pm Post subject:

Thanks for this Thomas and Antman -
I'm still trying to locate a daughterboard that's appropriately cheap - but it looks like a project that would make my wife really pleased. And that's rare. Wink

bruce

Thomas Henry · Posted: Sat Dec 15, 2007 5:31 pm Post subject:

Hey RF,

I hope you find a board, for this is truly one of the sleeper projects of the decade. I suppose pleasing a wife can be seen as the sweetener, but for my part it's being able to do large, orchestral recording now. I still can't believe I ignored Antman for so long; this is the project that changed the way I do music.

And by the way, how far north are you? I keep hoping for some of that -60 degrees that hit Tower a while back. It aids our reputation, don't you think?

Happy GM-ing,

Thomas Henry

Thomas Henry · Posted: Sat Dec 15, 2007 5:35 pm Post subject:

RF · Posted: Sat Dec 15, 2007 9:16 pm Post subject:

State Machine · Posted: Sun Dec 16, 2007 7:51 am Post subject:

Thomas Henry · Posted: Sun Dec 16, 2007 12:55 pm Post subject:

A little more detail on the power supply:

Since the drain is so low, a person could use the smaller 78Lxx/79xx series for all three regulators. However, the +12V side is pushing 80mA, which really should call for a heatsink with this smaller regulator. (I believe the part is rated at 100mA). Rather than do that, I simply used the larger 78xx/79xx units which have more surface area. Heat sinks are not required, and indeed the chips run dead cool. I sort of felt things would be simpler and take less room in the long run if I did it that way.

Thomas Henry

Dan Lavin · Posted: Sun Dec 16, 2007 5:48 pm Post subject:

Just to second Thomas' recommendation on power supply voltage regulators, I've used the 7805, 7812 and 7912 regulators without heatsinks on the Yamaha db50XG board, (which is the largest daughterboard I've used to date), with the same results: they all run cool.

Thomas Henry · Posted: Sat Dec 29, 2007 7:02 pm Post subject:

Okay, attached is an .mp3 file of a song which illustrates just a fraction of what the GM-Voice is capable of (and I mean that...this thing's got features that just go on and on).

In the tune you'll hear the GM-Voice doing:

tenor sax
English horn
bassoon
harpsichord
brass section
tubular bells
reed organ
bottle blow
acoustic bass
violin
vibraphone

Other instruments include a Casio CZ-1000 doing the harmonic lead, sfz (free software synth on laptop) doing tympani, triangle and assorted percussion, and a Les Paul guitar. The song was recorded on a Boss BR-600, using a DOS Cakewalk sequencer running on an old 486 machine.

Please note that all of this is going on real time---there was no multitracking or bouncing! The GM-Voice is capable of doing a minimum of 24 simultaneous voices. As I've mentioned before, this is the best 25 bucks I've ever spent and I regret not listening to Antman some ten years ago when he first proposed the project.

I've just scratched the surface of what thing's capable of, but perhaps this song will give you a feel even if you don't like the tune.

Play it loud!

Thomas Henry

Saucy Jack.mp3

Description:

"Saucy Jack," (c) 2007 Thomas Henry. For personal use only; please don't copy.
Illustrating just a few of things the GM-Voice can do...

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Saucy Jack.mp3

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Scott Stites · Posted: Sat Dec 29, 2007 11:04 pm Post subject:

Frikkin awesome Cool

State Machine · Posted: Sun Dec 30, 2007 9:57 pm Post subject:

Wow, fantastically composed !!! I am impressed most by the drum tracks composition and the sounds this thing can create ! Cool

Bravo !

Bill