The library for the free and open source VCV Rack has been on fire lately. But this one is a standout: 4ms has a sprawling library of ROMpler modules based on classic drum-machine samples. And don’t let the “ROMpler” part fool you: those samples are ready for full voltage control. Honestly, it almost feels like having circuit-bent versions of these classic machines. They’ve put a bunch in there: Ace Tone Rhythm King, KR55, Casio SK-1, CR-78, TR-727, TR-606, Synsonics, plus a full set of acoustic sampled modules, and Orchestral Hits. (Yeah, let’s rave!) Now, we’ve seen other ROM-based modules and occasionally physical modules — Erica Synths has even done it in pico modules. But before you imagine this is just about dialing up some canned drum sounds, you get CV inputs for length, speed, pitch, and sample select (depending on the module). That allows for some serious patching mayhem.…