16tone's Vogue Quattro is a free standalone four-voice synth for Intel Macs . It has microtonal capabilities and it comes with a library of 3,000+ tuning files.
The direct download link is here Specifications:

• four-voice polyphonic PCM synthesizer
• three oscillators per voice, each endowed with square wave sub-oscillator (1 or 2 octaves lower)
• true monophonic mode (plays three voices at unison, nine oscillators in total)
• 88 raw waveforms including white noise
• single LFO with 6 waveforms
• ring modulator
• easy-access modulation matrix
• scale-relative pitch-bend (self-adapting to tuning scale steps with microtonal precision)
• 64 factory preset programs
• receives MIDI tuning standard SysEx messages
• compatible with Max Magic Microtuner mtx - tuning files
• includes library of 3,000+ tuning files

This is a standalone synth so you'll need Cycling '74 (free) Soundflower to re-route its output and be able to record it .
Pricing and Availability:
Free download More information:

• 16tone

< More From: 16TONE

• Vogue Updated 29-Mar-11
• Free Mac Synth Updated 19-Oct-10
• Microtonal Mac Synth updated 31-Aug-10

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