Shell

Audio Waveshaper for Unique Harmonic Mixes

Exploring how to make a waveshape of the harmonics of the Fibonacci series, we designed a module with unbelievable variation of the first five harmonics. Dark, dramatic and fuzzy.
While Blip! is all about keeping the low harmonics empty, Shell is all about playing with the balance between them.

Why would you want to do that? Because in nature waves with the harmonic relationships of the classic synth waveshapes (where each harmonic is softer than the previous) are rare and unappealing: if you look at the spectra of most notes on most classes of instruments, the fundamental rarely is the usual dominant harmonic. Even the flute: we often think it is pretty much just a sine (the first harmonic only), but as the player plays louder or changes angle of the jet, the dominant harmonic can be the the second or third harmonic! The fundamental waveshapes of classical synths make it harder not easier to get sounds with that kind of characteristic!

Modulation by external CV is quite gentle, not dramatic. This is a good module for knob-twiddlers. So the main way to get strong modulation effects is to vary the incoming amplitude.

Caveat: Shell works best with VCO signals that are close to the Eurorack standard of 5V PP (i.e +/-2.5V). Many VCOs do not comply with the Eurorack “typical” values and produce much less. If you have such a VCO, you should boost the signal through some amplifier before feeding it into Shell. (We may have another solution to this next month.)

Audio Example:

SawDrone: Drone with three saw VCOs and three Shells going through the different settings.
(WAV file access also at http://electro-music.com/forum/topic-71087.html)

Elergy: Violin-ish patch, using Shell, Rasp, Splice and a digital Hi-Q EQ bank.

Power (Current): +12V: 10-30mA (depending on op-amp), -12V: 10-15mA, +5V NA.

Physical: 4HP (aluminium black writing on white) or 6HP wide, 60 mm deep, 16 pin power socket (10 pin can be used).

Status: RELEASED – IN STOCK (Rev 2)

EU and UK customers: ROHS PCBs (Rev 3) awaiting re-order, please enquire

More Info:

• Shell Waveshaper: the Backstory
• Panel
• Theory of operation
• Pricing and Purchasing
• fricko General Building Guide
• Rev 3 PCB:
  • Bill of Materials (BoM) (Rev 2 & 3 PCB)
  • Interactive Component Placement
  • Release Notes (Rev 3 PCB)
• Rev 2 PCB:
  • Bill of Materials (BoM) (Rev 2 & 3 PCB)
  • Release Notes (Rev 2 PCB)