Sound Module Version of the D-70
There is no sound module version of the D-70.
The closest relatives are the U-20, U-220 and the MV-30.
The U-20, U-220 and MV-30 also used RS-PCM technology and were compatible with the SN series PCM ROM card library (although not the accompanying parameter data cards).
The MV-30 even had the TVFs (Time Variant Filters) that are found in the D-70, but did not have patches or performances so it could not do splits or layers.
The U-20 and U-220 did have patches so they could do splits and layers but they lacked the TVFs so were not as versatile for synthesis or sound design.