The other day, whilst going through old PC hardware, I found my old ISA SoundBlaster 16, with the Yamaha DB50XG daughter board stuck to it.
Now the SoundBlaster 16 is useless in this day and age - you can’t even rip an FM chip off it - but the DB50XG is an interesting little sound generator. Which made me wonder, how difficult would it be to make a small box with a small PCB and some MIDIbox components?
There are several resources on the internet about either the Waveblaster or the DB50XG (like this one, this one and this schematic), but these deal with building a board that converts the TTL signals of the board to MIDI, via an opto-coupler and buffers for the MIDI Thru (the interface does not have a MIDI Out; at least, the DB50XG doesn’t).
Since the MIDIbox hardware also works on TTL level (right?), what would be needed, apart from a Core module and something like an AIN (for knobs), DIN (for buttons and data wheels) and/or DOUT (for LEDs) modules?
The MIDIbox boards would need to be able to handle MIDI In and Out (for proper MIDI ports), and an extra MIDI Out (on TTL level) to control the daughter board.
Software… that’s another issue, but it should be feasible enough.
I had a 1U DB50XG some years ago.. I didn’t convert any TTL signals (afaik), If I remember correctly, I just created a plexiglass case and powered it up. I had a reset switch, audio,midi and power connection.
Used it a couple of years.
Maby I was lucky… have you tried (without TTL conversion)?
Well, finding the DB50XG is not the problem; I bought it at a musical instruments shop way back, which has since long gone. The problem is that I’m not very familiar with the electrical properties of electronics: logically I understand everything; it’s when it gets to complex figures, capacitors and resistors that my mind draws a blank.
And, of course, I wouldn’t want to risk damaging the DB50XG. But it seems such an excellent project to convert it into a MIDIbox XG or something like that.
I think I will use searching for those posts as my wiki search-engine-how-to document. They’re there, but it took some trickery to find them. Hope they help
Get a midi spec for the thing and then build an MB64 around that.
Well, my EX5S is a rompler too, among other things, but you can control quite a few parameters. It’s been a long time since I last looked at the manual of the DB50XG (which comes with the complete MIDI specification) but you can control quite a few parameters, from what I remember. It’s not unlike the CS1x keyboard, and identical to the MU-10 module in regards to sound capabilities.
Admittedly, that’s not a lot of controls.
So on the one hand it’s a simple General MIDI device, but this being Yamaha, you have three effects processors as well, plus set of resonant filters. More info can be found at Sonic State. (Karaoke chip? Oh dear.)
This is the reason that I had this idea, because it’s such a lovely little board.
So… I had a look. My question about the two MIDI Outs may not have been entirely clear. What I meant is that there should be the usual MIDI In and Out, to communicate with the box. The In, well, that should be pretty clear, and the Out would do things like patch dumps.
However, apart from reacting to the messages coming from the MIDI In, the DB50XG would have to react to the signals coming from the Core module (turning knobs, pushing buttons, etc.), and these would be different from those going to the MIDI Out.
Unless it’s too much of a hassle, and not worth it, in which case the MIDI Out could be sacrificed.
But I think the second MIDI Out, at TTL level, might be connected to J11. However, this is the point where my understanding of the MIDIbox platform hopelessly falls short. Any hints in this regard would help me a great deal, because it looks like a Core (which I have one spare), a DIN and a DOUT (both of which still have to built into a SEQ box), an AIN (for the knobs or sliders) plus a small custom PCB would do the trick.
regarding db50xg, i know that somewhere, on internet, there are schematics to make a PCB to connect the db50xg via midi to a PC (for exampel), making it a standalone synth.
i had downloaded the files once, and i have to find it if you are interested.
moreover, there is a shareware editor for the db50xg (somewhere in the net…) which permit to use the daughterboard to its extreme (as for example making using 4 oscillator all together to make 1 voice).
Check this site - http://www.midiweb.de/ - there is a program called ‘XG-Gold’ - IMHO best editor for db50xg.
As You can see on the screens, there is a lot of things, which can be controlled real-time (4 parts, each with independent LP filter with envelope etc…).
In fact i was thinking about building dedicated midibox surface for db50xg in QS300 mode, but I didn’t realized this plan so far…
Just for the record, so I will need an extra module to extra the second MIDI out at TTL level from the core? Is there no way to extract it one way or another from J11, like the LTC board gets it from there?
Good luck man!
