The “Pocket Operator” family of mini synthesizers by Teenage Engineering are a bunch of small, ultra-portable gizmos you can use to create studio-quality music on the go.

Each one offers a unique set of sounds and capabilities — ranging from drums to basslines to keys to chiptune sounds to vocal sampling — and they can either be used separately or connected together to create your own little pocket band. You can listen to sounds straight from their onboard speakers, connect some headphones, or hook any/all of them into a sound system for live performances.

Here's the list of models:

• PO-12 / “Rhythm” ($59) — 16-sound drum machine and sequencer, perfect for making beats.
• PO-14 / “Sub” ($49) — Deep bassline synthesizer.
• PO-16 / “Factory” ($59) — Lead synthesizer for keys melodies.
• PO-20 / “Arcade” ($59) — Arcade sound/chiptune synthesizer and sequencer.
• PO-24 / “Office” (unavailable on Amazon as of writing) — Noise percussion drum machine and sequencer.
• PO-28 / “Robot” ($89) — Real 8-bit synthesizer engines for making live and sequenced melodies and leads.
• PO-32 / “Tonic” ($89) — Drum and percussion synthesizer and sequencer.
• PO-33 / “K.O.!” ($89) — Micro sampler with 40 seconds sample memory and a built-in recording microphone.
• PO-35 / “Speak” ($89) — Vocal synthesizer and sequencer with built-in microphone for sampling 8 different voice characters.

Every unit features 16 patterns, a 16-step sequencer, a built-in speaker, a fun animated LCD display (the graphics vary by model), a folding stand, 3.5mm audio I/O, a month of battery life and two years of standby time (on two AAAs), and more.

The models are caseless by nature, which is fine since all the sensitive stuff is hidden under the display. However, they do offer a silicone case if you feel like you need one.