The 285e frequency shifter shifts all harmonics by a fixed Hz amount, destroying harmonic relationships and creating inharmonic sidebands

Unlike a pitch shifter that multiplies all frequencies by a constant ratio (preserving harmonic intervals), the 285e’s frequency shifter adds or subtracts a fixed number of Hz from every partial. A 50 Hz shift on a 100 Hz fundamental produces 150 Hz, but its second harmonic (200 Hz) becomes 250 Hz — now at a 5:3 ratio rather than 2:1. Small shifts (a few Hz) create a slow beating effect with a sense of depth; larger shifts produce characteristically metallic, inharmonic textures. The internal reference is voltage-controllable from 1 to 1 kHz. The 285e also includes a balanced ring modulator on the same panel.

Examples

Set shift to 2 Hz and route to a stereo pair — left gets +2 Hz, right gets −2 Hz — for a subtle stereo widening and depth illusion. Increase shift to 200 Hz for metallic, inharmonic timbres.

Assessment

Explain why a 50 Hz upward frequency shift applied to a note with fundamentals at 100 Hz and 200 Hz yields inharmonic results. Contrast this with a pitch-shifting operation that preserves the harmonic ratios.