TC Works' Mercury-1 ($199) is a multitimbral analog-modeling software synthesizer that provides up to four independent monophonic voices at once.

A single Mercury-1 voice has dual oscillators, a noise generator (oscillator 1 only), and an additional suboscillator. The oscillator section offers a choice of sine, sawtooth, triangle, square, or pulse waveforms with pulse-width modulation. You can use oscillator sync or add ring modulation, both of which can be modulated by the LFO and the envelope generator. Many additional parameters, including Pulse-Width Modulation, Wave Selection, Sync, Mix, Filter Cutoff Frequency, and Oscillator Detuning, can be modulated with assignable MIDI commands.

The single LFO offers a choice of sine, sawtooth, square, and sample-and-hold waveforms, and you can modulate LFO frequency with MIDI Clock as well as define the number of LFO cycles per beat. When the LFO is synchronized to MIDI Clock, the LFO Rate parameter automatically displays the tempo base.

The 24 dB-per-octave resonant lowpass filter has a programmable LFO amount, and you can modulate the filter's cutoff frequency by keyboard position. (Modulation amount is scalable.) Either of the two envelope generators is assignable to the filter, and you can invert the filter's envelope.

You have a choice of triggering the amp section with an envelope generator or with a simple gate. If gating is used, the second envelope generator is free to modulate another parameter. The amp's Drive parameter engages TC Works' SoftSat algorithm for simulated analog distortion effects.

Mac users need at least a G3, 64 MB of RAM (128 MB with Mac OS 9.0), and Mac OS 8.6. Windows users can use a Pentium ll or better with 64 MB of RAM and Windows 95/98 or NT 4. VST-compatible sequencing software is required for both platforms.