Lorelei

An analogue VCO built on discrete transistor OTAs, with quadrature sine outputs: two sines 90 degrees apart, and a square. One Shape control, a knob and a CV input with its attenuator, reshapes the three outputs together: the square's pulse width moves, the sine turns towards a triangle and the cosine towards a saw, and half-way the perceived pitch of both doubles. The X-mod input works like a sync that sets in gradually above about 3.3 V, so a sine, a ramp or a pulse each give a different result. The sockets light red or blue with the voltage on them.

Key features

• Three outputs: square/pulse, sine/pseudo-triangle, cosine/pseudo-saw
• Eight-position octave switch and a Tune knob of about one octave either way
• 1V/octave, linear FM and exponential FM inputs, the last with an attenuator
• Cross-modulation/sync input
• Sockets lit by their voltage (red positive, blue negative)