UniMatrix TVS Include The Digital Keyboard
Product Information
Specifications:
- Compatible with digital keyboard TVS models
- Requires intermediate level of electronics knowledge for
installation - Power: +10V and ground
- Midi In: Connects to rear I/O plate
- Data Signals: Available on large molex header connecting
keyboard to logic PCB - Stimulus Pins: Requires 5 wires for I/O 9-16 header
Product Usage Instructions
Installation:
- Ensure your TVS model has a digital keyboard compatible with
this modification. - Have a good understanding of electronics and access to the
unit’s PCB. - Connect power wires to CMOS IC pins 14 (+10V) and 7
(ground). - Solder midi wires to available pads on the UniMatrix PCB.
- Wire in data signals according to the provided wiring
instructions.
Configuration:
- Download the TVS file provided or use the Tubbutec
configurator. - Input specific information such as Midi Base Note,
Stimulus/Input Count, and Number of notes to populate. - Press the rotate button after inputting the required info.
- Check that the Note/CC Column descends in order: 7, 15, 23, 31,
39. - Export sysex or send directly from the webapp to complete the
UniMatrix install.
Midi Clock Output:
UniMatrix includes a midi clock output. Connector H on the mini
sequencer allows external clock input, but the pulse must be above
12V, requiring signal conversion with transistor logic.
Frequently Asked Questions (FAQ)
Q: Can this kit work with TVS models that have an analog
keyboard?
A: No, this kit is only compatible with TVS models that include
a digital keyboard.
Q: What level of electronics knowledge is required for
installation?
A: Installation requires a more than intermediate level of
electronics knowledge.
UniMatrix Oberheim TVS Installation By Rob Rosen
Note: Most TVS include the digital keyboard, aka diode matrix keyboard which this modification is compatible with. Some early TVS have an analog keyboard like an ARP 2600, and that can be easily identified by a transposition rotary switch rather than a transposition slide switch. If you have the earlier analog keyboard, this kit will not work at all.
This install guide assumes you are familiar with electronics to a more than intermediate degree. It also assumes you don’t need us to explain how to open the unit and access the
underside of the left hand controller where the PCB lives.
Here is a photo of the finished installation. Note another diode matrix product was installed previously and the solder work isn’t beautiful in this photo.
Mounting: The holes on UniMatrix are not big enough for american hardware. However, a 6/32 screw will fit with some encouragement. We removed 1 nut and replaced it with a ¼” standoff. We then affixed the unimatrix to this standoff with a nylon spacer between the PCB and the standoff. You may consider a 6/32 – M3 converting standoff.
Power: +10V and ground can be had from most CMOS IC’s on pin 14 and 7 respectively. Use a meter to confirm. The power wire in our kit came with 3 wires, the third unused, which we cut off.
Midi In: We mounted the midi jack on the rear I/O plate and ran wires to the Unimatrix. Since we did not want to splice wires, we soldered the wires to the available pads on the bottom of the UniMatrix PCB for midi.
Wiring In Data Signals: All needed signals are available on the large molex header that connects the keyboard to the logic PCB. NOTE: The header is a 15 pin header with 2 keying positions. The 9th pin has a physical plug for keying but is still counted in the pin count. This is especially important for the stimulus pins. The 2nd keying position is pin 15, which is unused.
Starting from the left, here is how to connect the first set of wires for I/O 1-8 on UniMatrix:
UniMatrix
Wire Header
1 Purple
E4
2 Blue
E7
3 Green
E5
4 Orange
E8
5 Yellow
E6
6 White
E2
7 Red
E1
8 Black
E3
For the “Stimulus Pins”, I/O 9-16 header, you only need 5 wires. The remaining 3 can be tied off or trimmed.
UniMatrix
Wire Header
1 Purple
E14
2 Blue
E13
3 Green
E12
4 Orange
E11
5 Yellow
E10
6 White
Unused
7 Red
Unused
8 Black
Unused
Once you have completed all wiring, it’s time to configure the UniMatrix.
If available, download the TVS file we made for Tubbutec. It should be all you need. In case it’s not, here is some specific bits of info for the configurator in the order they appear if they differ from the default values or values you can change to your liking (midi channel etc)
Midi Base Note: We recommend +12 or +24. No need to change this if you don’t want to. Stimulus/Input Count: 5 Number of notes to populate: 37
– Once you input this info, press the “rotated” button. – Go to the OUT 8 tab and ensure the Note/CC Column descends in this order: 7, 15, 23,
31, 39,
Go to the top of page and export sysex or send directly from the webapp. This completes the UniMatrix install
Optional: Tubbutec adds 2 midi-cv controller opportunities with UniMatrix. We have only tried using this to control the SEM filter. To add filter control by midi, do the following: In the configurator, go to the bottom and change CV1 mapping to Controller. Under Note/CC, change to 74 which is the standard “brightness” control in midi land. On either the bottom of UniMatrix or using the extra set of wires included, attach a wire to I/O pin 23. On the other end of the wire, you need to add a resistor and connect it to the filter summing node on the SEM. The filter summing node op amp is right above the filter molex header which is connector H. Since the UniMatrix only supplies CV from 0-5 volt, we need to double the power of the summing node which is typically supplied with 100k summing resistors as the SEM filter needs 0-10V to fully sweep the filter. Solder one leg of a 50K resistor to pin 2 of A19 (741 op amp). Solder the other end to the wire from UniMatrix. To add control of both filters, simply run a second wire before it hits the resistor to go to SEM 2 with another 50K resistor in the same manner. Tip: For true duophonic SEM fun with CC control, you can assign CV 2 to a different CC number and run pin 24 from UniMatrix just like above to the second SEM. Then you can control them individually! Or, you can use velocity instead to get more dynamics from your TVS via midi.
Another hint: UniMatrix includes a midi clock output. Connector H on the mini sequencer allows external clock, however the pulse must be above 12V, so you would need to convert the signal with transistor logic.
Documents / Resources
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Oberheim UniMatrix TVS Include The Digital Keyboard [pdf] Installation Guide UniMatrix, UniMatrix TVS Include The Digital Keyboard, UniMatrix TVS, Include The Digital Keyboard, Digital Keyboard, Keyboard |