I have seen many lab measurements of D&M and Yamaha AVRs and I believe their specified two channel output ratings are actually quite conservative more often than not. Here's one for the RX-A2010, the 2020 and 2030 will certainly be comparable.
Review: Yamaha Aventage RX-A2010 A/V Receiver Page 3 | Sound & Vision
STEREO PERFORMANCE, DIGITAL INPUT
Reference level is –20 dBFS; all level trims at zero. Volume setting for reference level was –3.
Output at clipping (1 kHz, 8/4 ohms, both channels driven): 161/255 W (22.1 /24.1 dBW)
Distortion at reference level: 0.02%
Obviouisly if the OP pushes more than 2 Soava-1 towers to deafening SPL (volume at +1 could be at such level if the source input signal is high enough) then he needs a higher end AVR or add external amps.