Echobode is a delay effect with a frequency shifter placed inside the feedback loop. The frequency shifter algorithm is inspired by the classic Bode Frequency Shifter (named after its inventor Harald Bode). The difference between a frequency shifter and a pitch shifter is that it shifts the audio spectrum linearly. E.g. an overtone series of 100, 200, 300 Hz can be shifted by 50 Hz to 150, 250, 350 Hz, making the overtones inharmonic. This effect in itself is great for creating metallic bell timbres, but putting it inside a delayed feedback loop opens up many other possibilities.
When a frequency shifter processes audio, two "sidebands" are generated, one that is shifted upwards and one that is shifted downwards. The challenge in creating a good frequency shifter lies in suppressing one of these sidebands (otherwise the effect sounds like a regular amplitude modulator). We are proud to say that Echobode features excellent suppression over the range of 40 Hz to 20 kHz. If you want less suppression there is a "sideband mix" parameter that you can adjust, allowing you to create amplitude and ring modulation effects.
Echobode features a unique "anti-reflection" stage that removes "negative" frequencies (frequencies that are shifted down beyond 0 Hz and would otherwise bounce back into the audible spectrum). This stage also eliminates frequencies that are shifted up over half the sample-rate ("nyquist").
Mixing a slightly shifted signal with the source signal creates phaser-like "beatings" and applying feedback (with a very short delay time) emphasizes this sound. The sideband suppression technology introduces additional "phase shifting" that adds further to this effect.
The delay time can be synchronized to tempo and it can be modulated to create chorus type effects. The delay uses an "all-pass interpolation" technique that is low on aliasing and will preserve all the high-frequency energy of your source signal (even when time is being modulated). Even with no frequency shifting taking place, Echobode is useful as a high quality echo effect with subtle phase smearing properties on the feedback.
A built-in sine LFO can be routed to modulate the frequency shifting amount, the phase shift or the delay time. The LFO can be tempo synchronized and put into stereo mode to generate inverse modulation for the right audio channel. Even in synchronized mode, rate changes are smooth and will not cause sudden jumps. Echobode has no latency and has a consistent sound on all supported sample rates. It is CPU friendly and automatically "suspends" itself, taking 0% CPU when its inputs and outputs are silent. You will find lots of CV inputs on the backside and separate outputs for the two sidebands. Bundled with the product are many patches, combinators and song files that will demonstrate the many different identities that this deceivingly simple looking effect can assume.