Pity the iPad. Unlike the Commodore 64, Apple’s wundertablet doesn’t come with a state-of-the-art SID synthesizer chip inside. Well, now emulation solves that problem.

SidTracker 64 is both an emulation of the SID sound chip on the Commodore computer line, plus a workstation for arranging your own songs. And it’s already got some songs to get you started, like the classic “Commando” by Rob Hubbard, which you can play or remix.

It’s loaded with all the usual production extras. And don’t let the “tracker” name put you off: you can play in real time, which naturally works well on the iPad:

The app emulates the later 8580 chip. That may displease purists who seek the original, but apart from some very specific glitches on the original 6581, the two are capable of producing basically the same sounds. And while the SID is associated with feel-good 80s video game lore, it’s really a beautiful and versatile synthesizer, in no way restricted to that particular genre. The work of Bob Yannes (who went on to found Ensoniq), it fits well into synth history.

SidTracker 64 adds a lot of powerful features – you can even play the output on a real Commodore computer if you’ve got one:

  • Audiobus 2, Inter App Audio, audio/.sid/prg export (email/Dropbox)
  • MIDI input (with key and controller mappings
  • MIDI clock input
  • Patterns with three voices, mute, per-step instrument changes
  • Per-step effects (volume, filter, speed)
  • (Glide/sustain/vibrato/filter & pulse reset/tie)
  • Loops, songs
  • Live and step recording


And of course, you have all the features of the SID itself:

SID synthesizer engine specs:
· Fully emulated SID 8580 R5 chip.
· 3 separate voices
· 8 waveforms – tri, saw, pulse with pwm, noise, trisaw, tripulse, sawpulse, nowave
· Wavetable editing
· 3 volume envelopes
· Dedicated vibrato controls
· 1 multimode filter LP/BP/HP (12/6/12db) with sweep envelope
· Filter table editing. Change filter cutoff and modes up to 1/240
· Hard sync and Ringmod per voice
· PWM sweep envelop
· PWM table editing
· Hard restart
· Variable emulation speed from 25-240hz (standard 50)
· 32 instruments per song (copy/paste/rename)

The developer has also done a comparison with the Waldorf Attack drum synth app. Fair points here, though I think they’re each great apps – you can just grab both of them:

Find it on the App Store. Going to give this one a try; I haven’t yet.

Congrats to Fredrik Segerfalk for this one. More: