OAudio subwoofer amplifiers
As well as the SGR amps, Audiomarketplace are also selling the somwhat more affordable OAudio 500w amp.
500 watt : OAudio
500W RMS into 4ohms @ 0.3% THD
420W RMS into 4ohms @ 0.05% THD
325W RMS into 8ohms @ 0.01% THD
S/N (A-weighted): 105dB
Lowpass Crossover: 40Hz to 120Hz, 4th order
Parametric EQ: 20Hz to 80Hz, 0 to -12dB, variable Q
Continuous Phase Adjustment
OAudio 500w amp at Audiomarketplace $495 AUD incl GST (29th June 2009)
The Manual and User Guide (links courtesy of pochoboy at AVS Forum)
http://www.oaudio.com/docs/subamp_variouseqsettings.pdf
This is straight off Collo's web site, and is the OAudio amp available in Australia.