Of course, Teenage Engineering is all about creative fun, so you can also use the rumble module to add haptic "bass" to the OP-Z. That's where Lofelt made its name, with the wearable "subwoofer" Basslet. Haptic "bass" (it's of course, not bass at all, technically) gives the illusion of hearing/feeling low frequencies through the smart conversion of those frequencies into tactile movement.

Originally, Teenage Engineering was going to bake compatibility with the Basslet right into the OP-Z. That feature never materialized, and Lofelt has since moved on to more extensive products (such as its collaboration with Razer). So it's good to see that the idea wasn't totally lost.

Haptics are becoming a popular way of incorporating new feedback into our gadgets. It's more than just having your phone in "vibrate" mode, as anyone who's ever felt the slightly creepy "heartbeat" vibrations from an Apple Watch can tell you. Companies like Lofelt are fine-tuning the experience so that the haptic sensation is nuanced and specific. You won't just feel the bass, you'll sense all its textures, much like standing in front of a speaker, or when that guy drives past with a $4,000 car audio system.

Rumble joins the oplab module (MIDi and CV connectivity) on the Teenage Engineering website today, for the aforementioned $89.