RMIF TI-3 AMPHITON

More actual pix - here

A true 8-voice analog polyphonic with KP580BM80A based controller, 16 digitally synced analog oscillators, 8 MOOG-like discrete ladder filters, 1 SAW_UP/SAW_DOWN/TRIANG/SQUARE LFO, 1 noise source, 256 memory presets in four banks (192 ROM, 64 RAM), sequencer and UP/DOWN/UP_AND_DOWN arpeggiator. Four AA type batteries are used for memory back_up. Modulation of pitch, VCA, VCF and waveform is possible. Polyphonic and monophonic modes are provided.

Monophonic mode is quite complex and unusual. Some of these sounds resemble ready chords sampled and played back at a different pitch. Monophonic portamento may be used in auto and antiauto modes (in terms of Roland SH101). Polyphonic portamento action sounds a little bit similar to JUPITER 8. The weight of this device is about 17-18 kilograms. Designed approx. 1985, assembled in CCCP Latvia.

It has two powerful features. The first one is that the waveform of each of the oscillators is programmable, i.e. rise time, pulse width and fall time (per cycle) can be adjusted . In other words if you, say, set the maximal rise time, pulse width to zero and fall time to zero too, you will get a nice SAW, if the rise time is equal to the fall time and the pulse width is zero, this will be a good TRIANGLE. If the former two are zeros and the latter (I mean pulse width) is somewhere between MIN and MAX the signal waveform will be PULSE. If the parameter settings are not so extreme and some modulation is applied this will be a ...e-eeh..uu-uhm.. VARIABLE GEOMETRY WAVEFORM !!!

Another one (powerful feature) is a 6-parameter VCF EG . Three knobs are levels and the rest three are durations. This is something like ADSR with a phase reverse switch, but these levels can be set without any limitations. During the attack phase the control voltage varies from LEVEL 3 to LEVEL 1, then from LEVEL 1 to LEVEL 2 (decay-like) and then from LEVEL 2 to LEVEL 3 (release). Mention should be made that LEVEL 1 can be lower than LEVEL 3 meanwhile LEVEL 2 can be higher than LEVEL 3!

Filter is 24dB/Oct lowpass transistor ladder type built of discrete transistors and KP198HT1 transistor array chips (CA3046-friendly, not pin to pin compatible according to reference book). Filter cutoff frequency is defined by EG, control pedal, pitch bend wheel (a bit like in JUPITERS), LFO and keyboard. Keyboard tracking is OFF or FULL .
VCA EG is a 5 parameter ADSR - like conditional only (in terms of memorymoog). MIDI was not installed in early versions, although the circuit board layout includes all connections for the UART, optocoupler etc.

Manual - here  
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