the pro 4 bridges at 4 ohms only..you can run 2 ohm speakers on each individual channel.................Technical Specifications Output Power Rating Mono-Bridged: 1600 Watts RMS @ 4 Ω (1200 Watts continuous), 3% THD Mono-Bridged: 1200 Watts RMS @ 8 Ω (900 Watts continuous), 3% THD 2 x 900 Watts RMS @ 2 Ω (600 Watts continuous), 3% THD 2 x 625 Watts RMS @ 4 Ω (490 Watts continuous), 3% THD 2 x 350 Watts RMS @ 8 Ω (300 Watts continuous), 3% THD ...............this is directly from the manual.............so....on each of two independent channels...you can run either 2..4..or 8 ohm speakers...but you can only use one 4 ohm speakers in the bridged mode according to the manual..the amp will not do 2 ohms "bridged".. but it will let you run 2 ohm cabs on the individual channels at the same time..I have run multiple cabs in a variety of configurations on mine.
Correct. My apologies, its been awhile since I've fired mine up.