[sdiy] Legal issues of cloning

[Florian Anwander]

Hello Bob

Am 08.10.2013 14:18, schrieb Bob Weigel:
>> In 1974 came the SH-3 still with the diode ladder filter,
>
> Maybe I've been told wrong.  I haven't actually verified what my 3a has
> in it but I think it's another Roland design and the 3 had the moog
> filter from what i've been seen in all references so far.

You simply may have a look at the service manuals:
http://www.synfo.nl/servicemanuals/Roland/SH-3_SERVICE_NOTES.pdf pg.14
http://www.synfo.nl/servicemanuals/Roland/SH-3A_SERVICE_NOTES_5th.pdf pg-22
http://www.synfo.nl/servicemanuals/Roland/SH-2000_SERVICE_NOTES.pdf pg.13

SH-3 -> diode filter (from the beginning)
SH-2000 -> first Moog, later transistor-diode-ladder
SH-3a -> Moog filter

According to Peter Forrests A-Z the SH-3a was sold until 1981 (so lets 
assume produced maybe until early 1980), and there never was a change of 
the filter Design. So if there would have been any serious legal issues 
between Roland and Moog, Roland would have switched back to the diode 
ladder.

Florian