JamEngine vs Music Box Retro Go

JamEngine is a real-time music generation app that puts a full backing band in your pocket. Choose from 15 musical styles, pick your key and tempo, and JamEngine instantly creates authentic, genre-appropriate arrangements, complete with MIDI drums, bass, guitar, piano, brass, and woodwind instruments. Whether you're a guitarist looking for a rhythm section to practice over, a songwriter sketching out chord progressions, a jazz player working on improvisation, or a producer hunting for inspiration, JamEngine gives you a responsive, endlessly variable musical companion. 15 STYLES TO CHOOSE FROM Rock · Hard Rock · Classic Rock · Metal · Pop · Ballad · Blues · Slow Blues · Jazz Swing · Jazz Ballad · Funk · Bossa Nova · Reggae · Country · Lo-fi Each style comes with genre-authentic drum patterns, bass lines, guitar voicings, keyboard parts, and horn arrangements. 12 INSTRUMENTS Build your arrangement from a roster of 12 instruments, each with realistic General MIDI sounds: • Drums · Bass · Electric Guitar · Acoustic Guitar • Piano · Organ · Strings • Trumpet · Trombone · Alto Sax · Tenor Sax · Clarinet Mix and match any combination. Each instrument has independent volume, mute, solo, pan, density and 11 variation levels to control the complexity and character of its part. SMART CHORD PROGRESSIONS Build chord progressions using the grid editor or the interactive Circle of Fifths, a visual tool that highlights diatonic chords in your selected key, so you can see at a glance which chords belong together. Start from scratch, or load one of the built-in templates: I-IV-V, I-V-vi-IV, ii-V-I, 12-Bar Blues, Jazz Turnaround, and more. Choose from 18 chord types including major, minor, seventh, diminished, augmented, sus, and extended chords. FLEXIBLE TIME & KEY Play in any of 7 time signatures, 2/4, 3/4, 4/4, 5/4, 6/8, 7/8, and 12/8, with BPM from 40 to 300. Tap tempo to match a song. Select any of the 12 keys in major or minor. Change key mid-session and your chord progression transposes automatically to preserve harmonic relationships. VARIATION RANDOMIZER Enable the variation randomizer and JamEngine will shuffle instrument variations at musically appropriate boundaries, every 4 or 8 bars, keeping your practice sessions fresh and unpredictable without you lifting a finger. EXPORT YOUR SESSIONS Capture your jam as a WAV, M4A, or multitrack MIDI file. Use export to bring your arrangements into your DAW for further production. SONGBOOK Save your favorite sessions, style, key, tempo, chord progression, and instrument setup to your personal Songbook. Load them instantly to pick up where you left off. CUSTOM SOUNDFONTS Import your own SF2 SoundFont files to customize the sound of every instrument. FREE TO START, PRO TO UNLOCK EVERYTHING JamEngine is free with 4 styles (Rock, Metal, Jazz Swing, Lo-fi), 3 song saves, and all playback features. Upgrade to JamEngine Pro for a one-time purchase to unlock all 15 styles, unlimited song saves, and full export capabilities.

Music Box Retro is a precision-crafted virtual music box built with AVAudioEngine bell-tone synthesis, delivering authentic plucked-string timbre for 6 classic melodies. TECHNICAL HIGHLIGHTS - Custom AVAudioSourceNode renders each note as a sine wave with harmonic overtone (12% third harmonic) and exponential amplitude decay — matching the acoustic signature of a real music box - 6 MIDI-encoded melodies: Twinkle Twinkle, Ode to Joy, Brahms Lullaby, Canon in D motif, Fur Elise motif, Sakura - Progressive unlock system: melodies unlock at 3, 8, 15, 25, and 40 total play counts - Playback speed: 0.5x to 2.0x in 0.1x increments - UIFeedbackGenerator haptics synchronized per-note - AppStorage-backed persistence for play count and selected melody - Portrait orientation only - Forced dark color scheme PRIVACY AND DATA Music Box Retro operates entirely on-device. No network requests, no analytics, no crash reporting, no third-party SDKs. Zero data collected or transmitted.