> the reason i think is that the triangle wave is much easier to
> produce than the sine.
>
> correct me if i'm wrong, Dieter.

Whenever one designs an oscillator one has to decide which is the core
oscillator (e.g. sawtooth for A-110, triangle for A-111 and most of the
LFOs, sine for A-143-9). The other waveforms have to be derived by waveform
converters from the core waveform which always leads to imperfections
(except rectangle which is easy to generate by a comparator). The A-143-4
uses a triangle core. A voltage controlled oscillator with a perfect sine is
already available: A-143-9

If we expand the A-143-4 by everything that is available in other
oscillators (additional waveforms, range or octave switches, hard sync, soft
sync, linear FM, additional CV inputs, LED display ...) the front panel
width and the price will increase and the advantage of a compact module with
only the most important functions is lost. The problem is to find the right
compromise between functions and price.

Best wishes
Dieter Doepfer