I have three SA-XR55-57 for years. They were so cheap as s/h, 70-80 euros. I used them in active system and as power amps for 4 diy multisubs. Just to mention, one SA-XR55 in dual-amp mode works about ten years without any problem on 1,6Ohms ribbon bass panel. Unbelievable. All works last 15 years without any fault.
Also have Panasonic SA-XR700 which works even in tri-amp mode (in stereo, you have 3 amp for each channel) theoretically, 300W/6Ohms per side.
Also have Panasonic SA-XR700 which works even in tri-amp mode (in stereo, you have 3 amp for each channel) theoretically, 300W/6Ohms per side.