Roland D-70 DLM "wavetable" synthesis 

Quote from the original Roland D-70 brochure, May 1992:
DLM (Differential Loop Modulation) lets you create your own customized waveforms for synthesis. DLM's start point and loop length parameters allow you to specify the part of a waveform you want to use. Then complex looping functions using advanced interpolation technology truncate and modulate the part you select to create a new waveform. The resulting waveform includes many inharmonic partials, ideal for TVF processing or producing unique sounds such as a ring modulation effect. DLM features two modes, each with definable Start Point (0-127) and Length (o-128), giving you 32,768 different combinations of DLM parameters from a single waveform to make your sound creation possibilities practically limitless.
You can use DLM to modify any of the D-70's internal and external sounds, and by processing DLM-modified sounds with the TVF you can produce extreme tonal changes. For instance, you can turn an acoustic piano into a synthesized brass sound, or even a crash cymbal into a distorted guitar! Because DLM is an intuitive and simple process, it's easy to experiment and explore the wide variety of new sounds you can create.