Sound of Shadows


Call (415-554-1977) or email for availability.

Flight of Harmony's Sound of Shadows (SoS) is a voltage-controlled (VC) digital delay module based around the PT2399 echo IC1 from Princeton Technology – which was, by the way, originally designed for Karaoke equipment.

The SoS is essentially two separate modules: a delay and a voltage-controlled amplifier (VCA). The focus of the SoS was the delay while the VCA was thrown in because half of an LM13700 IC was unused, so the VCA is very basic.

As with all f(h) products, the SoS was engineered towards maximizing functionality while keeping cost as low as possible. If some aspects of the unit seem awkward, it is most likely due to this. The goal is to make unique, useful, enjoyable, and affordable instruments, not just hoover2 out your bank account.

And remember: every instrument has its quirks and unexpected aspects, so RTFM3! All the way through! Specific quirks are mentioned in the description of the particular feature they apply to, so please read this through before emailing!


Assembled Sound of Shadows digital delay module DC power cable – 9” Ribbon cable (Doepfer standard) M3x0.5x5mm Stainless-Steel machine screws M3 Nylon washers

  • Module width: 12hp
  • Supply Voltage: ±12VDC
  • Supply Current (max draw @ ±12V): +12V:51mA -12V:-21mA
  • Max. Input Voltage (@ ±12V): 10Vp-p
  • Max. Output Voltage: 6Vp-p
  • Input & Ouput (I/O) coupling: Direct*
  • Output Impedance: 1kO
  • Control Voltage (CV) inputs: ±Vsupply
  • CV input coupling: Direct
  • CV input impedance: 100kO
  • Mounting Depth: 50mm (~2″)
  • Delay Length: Min: ~31.3ms Max: ~342ms

For more details Download the Manual

Flight Of Harmony Plague Bearer + Sound Of Shadows from Paul Durso on Vimeo.