By SimonInAustralia
Tue Nov 06, 2012 6:20 pm
I mentioned this in the MPC3000LE Roll Call thread, but have had a couple of people ask me for some more info, what parts were used, etc. Will add some more info on what parts I used, how it was wired up, and some photos, when I get around to it.
If you incorporate this into your MPC3000, please put some video/photos/info/etc. on what you did in here as well.
AKAI MPC3000 IB-CRT-RGB CONTROLLER VGA cable/box:
From the YouTube video description...
If you look at the IB-CRT manual, you can see that out of a standard red/green/blue VGA output signal which is normally sent into a VGA monitor, only the green signal is used/connected, which is why the MPC3000 VGA display is normally green...
As you can also see, the green signal is a separate signal to the horizontal and vertical sync signals, which shows that it has a separate sync signal, rather than a sync-on-green signal, as is often incorrectly stated in relation to the IB-CRT and compatible VGA monitors.
The AKAI MPC3000 IB-CRT-RGB CONTROLLER box goes into the middle of a VGA cable that has been cut in half, all pins/connections in the VGA cable pass straight through the box, except for the green signal.
Inside the box, the single green output signal from the IB-CRT is fed to the centre pins of the three red/green/blue switches.
This allows the green output signal (pin 2) from the MPC3000 IB-CRT VGA output to be sent to any combination of the red/green/blue signal inputs (red=pin 1, green=pin 2, blue=pin 3) of the VGA monitor.
When selected, the "on-full" position of each 3 position IB-CRT-RGB red/green/blue switch routes the green IB-CRT output signal directly to each of the red/green/blue inputs of the VGA monitor, the "on-variable" position of each switch routes the green IB-CRT output signal through a potentiometer each before going to the red/green/blue inputs of the VGA monitor, the third "off" position of each switch sends none of the green IB-CRT output signal to that respective colour input of the VGA monitor, thereby allowing varying amounts (or none) of each colour to me mixed in, giving a wider range of colours.
It is a very simple circuit, the potentiometer values could be better chosen for a wider range of attenuation of each colour signal.
It could also be installed internally to the MPC, but I didn't want to drill any holes in my MPC for access to the switches/pots, so I inserted it inline, within a project box, in the middle of a VGA cable.
If you didn't want the control, you could probably reroute the green signal internally inside the MPC3000 on the VGA connector daughter-board, to either the red or blue pins, as well as, or instead of, the normal green pin connection, to hard wire in an alternative VGA output colour to the standard green.
If you wanted more control, you could probably wire up and program a circuit/microprocessor to output the signal as a particular colour based on incoming MIDI CC/note/etc. messages. Then you could have it change colour from the MPC sequencer, changing colours within beat/songs, or have colours set and changed for/between each song, for example.
If you incorporate this into your MPC3000, please put some video/photos/info/etc. on what you did in here as well.
AKAI MPC3000 IB-CRT-RGB CONTROLLER VGA cable/box:
From the YouTube video description...
Akai MPC3000LE, with homemade VGA cable/box to enable switching the normal green only VGA output signal from the Akai MPC3000 IB-CRT VGA option to any combination of the red/green/blue signal lines into the VGA monitor.
Each of the sends to the red/green/blue lines of the monitor can be switched between off/on-full/on-variable.
It is just a simple homemade prototype idea with 3 switches, 3 potentiometers, a project box, a VGA cable, and a laser printed label.
If anyone makes one with a nicer engraved, or similar, metal faceplate, please make me one as well
If you look at the IB-CRT manual, you can see that out of a standard red/green/blue VGA output signal which is normally sent into a VGA monitor, only the green signal is used/connected, which is why the MPC3000 VGA display is normally green...
As you can also see, the green signal is a separate signal to the horizontal and vertical sync signals, which shows that it has a separate sync signal, rather than a sync-on-green signal, as is often incorrectly stated in relation to the IB-CRT and compatible VGA monitors.
The AKAI MPC3000 IB-CRT-RGB CONTROLLER box goes into the middle of a VGA cable that has been cut in half, all pins/connections in the VGA cable pass straight through the box, except for the green signal.
Inside the box, the single green output signal from the IB-CRT is fed to the centre pins of the three red/green/blue switches.
This allows the green output signal (pin 2) from the MPC3000 IB-CRT VGA output to be sent to any combination of the red/green/blue signal inputs (red=pin 1, green=pin 2, blue=pin 3) of the VGA monitor.
When selected, the "on-full" position of each 3 position IB-CRT-RGB red/green/blue switch routes the green IB-CRT output signal directly to each of the red/green/blue inputs of the VGA monitor, the "on-variable" position of each switch routes the green IB-CRT output signal through a potentiometer each before going to the red/green/blue inputs of the VGA monitor, the third "off" position of each switch sends none of the green IB-CRT output signal to that respective colour input of the VGA monitor, thereby allowing varying amounts (or none) of each colour to me mixed in, giving a wider range of colours.
It is a very simple circuit, the potentiometer values could be better chosen for a wider range of attenuation of each colour signal.
It could also be installed internally to the MPC, but I didn't want to drill any holes in my MPC for access to the switches/pots, so I inserted it inline, within a project box, in the middle of a VGA cable.
If you didn't want the control, you could probably reroute the green signal internally inside the MPC3000 on the VGA connector daughter-board, to either the red or blue pins, as well as, or instead of, the normal green pin connection, to hard wire in an alternative VGA output colour to the standard green.
If you wanted more control, you could probably wire up and program a circuit/microprocessor to output the signal as a particular colour based on incoming MIDI CC/note/etc. messages. Then you could have it change colour from the MPC sequencer, changing colours within beat/songs, or have colours set and changed for/between each song, for example.