ARPJAM Studio vs 1981 FM

No sequences. No loops. A generative synth that plays on by your rules. And you can play right along. Key, scale, density, complexity — just set the rules, and five machines (arpeggios, bass, drums and a sampler) keep playing, with a different phrase every time. What you shape is not a song — it is a way of sounding. No AI picks the notes: your rules and probability do. Move a slider and the sound changes shape without ever stopping. Density, contour, filter, tape movement. It is built so that nothing you touch can break it. Then play right along with your own fingers. The on-screen key pad holds only the notes of the current scale, so nothing goes off-key. Play ARP A, ARP B, BASS or DRUMS, or connect a MIDI keyboard. What you play can be captured into the looper. ■ Five machines • ARP A / ARP B — two independent arpeggio engines. Ten arpeggio types, including Phrase (builds melodies) and Fingerpick (fingerstyle guitar) • BASS — a dedicated bass engine (STEP / COMPLEXITY / OMIT / PATTERN) • DRUMS — a drum machine built from probabilities (KICK / SNARE / HIHAT / NOISE) • SAMPLE — record one bar, slice it, rearrange it • Chord progressions (presets / automatic / 16 custom slots), ten time signatures, six LFOs ■ Slice (SAMPLE) • Record one bar from a mic or line input, with count-in and click • Record the app itself (ARP A / ARP B / drums), and overdub onto it • Load audio files — and the audio from a video file • Up to 64 slices, ordered by the same rules as the arps: direction, reverse, octave, probability, groove • STRETCH (on by default) — change tempo without changing pitch • Its own filter, envelope and delay / reverb sends ■ Play • On-screen key pad — always in scale; play ARP A, ARP B, BASS or DRUMS • PEDAL (sustain) and a one-bar looper that records how hard you played and transposes with the chords • MIDI keyboard input (ARP A / ARP B / BASS; damper pedal, pitch bend, standard control changes) • XY pad and performance FX that work only while held ■ Sound (11 voices) • Piano — three velocity layers, stereo, damper release • Electric piano — harmonics shift with how hard you strike • Nylon-string guitar — synthesised with a physical string model • Marimba, kalimba, handpan and chime — struck instruments, measured from the real ones and synthesised • Waveforms (sine / triangle / saw / square) plus an acid filter • Filter, ADSR, five drive types, tremolo — shaped per voice • Delay, reverb, Glitch, Granular • DRIFT / FLUTTER — tape movement on the synth voices and the live input alike • Concert pitch A=415–444 Hz ■ Connect • AUv3 plug-in — as an instrument, as an effect, and as a MIDI effect • Ableton Link, MIDI Clock, MIDI out (ARP A / ARP B / BASS / DRUMS), LFOs and XY as MIDI CC • External audio input (line / microphone) • Background playback — keeps playing when you switch to another app (iPhone / iPad) • WAV recording and export One-time purchase. No subscription.

1981 FM writes complete tracks. Press generate and you get 64 bars with an intro, verses, choruses, a break and an outro, played by a four-operator FM synth. Lead, bass, arp, pad and a drum machine, through chorus, delay and reverb. Nothing is sampled. Every note is made on the fly and no two tracks come out the same. The music comes from chaos maths. A Lorenz attractor shapes the melody, rhythm and mood. A Hénon map keeps the arpeggio moving. A logistic map handles the drum fills: turn it down and they repeat every bar, turn it up and they never do. Chaos on its own is noise, so a small model filters it. It gets rewarded for consonant intervals and practises over the chord changes before it writes anything. The CHAOS / POLICY slider decides how much say each one gets. Ten styles, and they are properly different. Funk plays a 16th-note slap line with ghost notes between the backbeats. Bebop walks the bass and puts the ride in charge of the time. Bossa runs a clave. Space strips the kit back to a pulse. Every track is built from its seed. Write the seed down and you can have that exact track again, note for note, whenever you want it. You can play over it, too. The pads are the notes of the song's key rather than a piano keyboard, so nothing you touch is wrong, and the sixteen-step lane runs in time with the song and follows your host. Both play any part you like: lead, bass, arp or pad, through that part's sound and out on its MIDI channel. Choose which sections the lane plays in - just the choruses, say - and preview it on its own without starting the song. Turn on RADIO and it keeps playing, picking a new key, mode, style and tempo for each track. You also get: • 10 styles, 6 modes, 12 keys, tempo and density • Four-operator FM engine, 6 algorithms, 11 presets, random patch • Five-part mixer, chorus, delay, plate reverb and filter • A PLAY panel: pads in the song's own key, and a 16-step lane running in time with the song and only in the sections you pick • MIDI in, so your keyboard plays whichever part you have selected • MIDI export: five tracks, one per part • Live spectrum, waveform and a view of the chaos engine at work Two Audio Units, an instrument and a MIDI processor. Each part sends on its own MIDI channel, drums on 10, so one instance can drive five instruments. The MIDI version passes your keyboard through instead of swallowing it. Both follow your host's tempo and transport. One install registers both. The app is free and nothing in it is held back. Using the Audio Units inside other apps is a one-time purchase, and each AUv3 session plays for two minutes first so you can try them properly. No account, no ads, no subscription. Works offline.