This has all the features of a regular DS201, but with the controls nudged up slightly to make room for two more knobs in each channel. These control a new creative feature which started life in the Drawmer MX range — Peak Punch.

The original idea of Peak Punch was to enhance drum sounds by creating a momentary boost in energy as the gate opened. For example, a kick drum exceeding the threshold level would open the gate and, at the same time, have a few dBs of level added over the first few milliseconds to give it more impact. However, in the DS501 this idea has been taken further. While the whole signal can be boosted by a user‑adjustable amount (via the Level control) if desired, a second mode also allows this added energy to be passed through a broad tuneable band‑pass filter. Above the two extra knobs is a three‑way toggle switch which selects between these two modes and a bypass of the Peak Punch facility. The filter's centre frequency is continuously variable from 75Hz to 16kHz using the Tune knob.

All audio connections on the DS501 are via balanced XLRs, though these can be used unbalanced as long as pin three is shorted to ground. The external side‑chain Key Inputs are provided on standard quarter‑inch jacks.