Roland Clan Forums

Could someone please explain what DLM ("Differential Loop Modulation") is?

Thanks.

Try this thread: software upgrades (ideas)

Beyond what is in the D-70 manual, I really don't know.

Regards
Andy

Its some kind of weird looping of waveforms that creates extra harmonics (usually buzzy sounds) or edgy sounds from any waveform in the D-70. Never heard of again after the D-70 as far as I know.

Leh173 is correct. Basically you can take a smaller chunk of any of the waveforms and loop it to make a different wave. It was an idea to stretch the usefulness of the sounds in a time where memory was limited, but because the entry and exit points of the created loop were pretty much arbitrary and the resulting sounds were so similar even when using different waveforms, the idea never took off and it was abandoned after the D-70.

Would have been awesome if you could have fine tuned the loop points.

From the elegant full colour 10-page brochure from May '92:

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.