Tape character

The parts of a Space Echo that are about the machine rather than the memory. All are off by default.

Control	What it does
Wow	Slow, drifting speed wobble (about 0.5 Hz, up to 6 ms).
Flutter	Fast speed wobble (about 7 Hz, up to 0.5 ms).
Tape Drive	Soft saturation of the echo, transparent for quiet signals; it also shapes what feeds back.
Hiss	Tape noise on the echo; with feedback it gets recorded along with the repeats.
Feedback Bass / Feedback Treble	±12 dB shelves (250 Hz / 3 kHz) inside the feedback path: each repeat gets thinner or darker, as on the RE-201.
Spring Level / Spring Decay / Spring On Dry	A spring reverb (dispersive allpass chain in a damped loop) on the echo, and optionally on the dry signal as in the RE-201’s reverb modes.

All of these glide when you move them, so they can be automated without clicks.

Changing the repeat rate

On a tape echo, changing the tape speed changes the pitch of what’s on the tape. Here, each trace remembers the trace length it was recorded at. When you change the trace length (or the tempo), Length Mismatch decides what old traces do:

Mode	Old traces…
Varispeed	…play faster or slower to fit, so their pitch shifts like tape. Halving the repeat rate plays them an octave up.
Cut	…play as recorded.
Loop	…repeat if shorter than the new length.
Stretch	…are time-stretched to fit, keeping their pitch (a phase vocoder; see Spectral).

Try it with Freeze Memory on: store a few bars, then change Trace Length (Sync).