1.The B-1 is the F-1 follow up model?
No, the B-1 is an additional unit in same size as F-1 but with many more functions. Main application is the bass extension and/or low bass filter for every speaker. With activated HIGH CUT it turns into a subwoofer crossover with parametric equalizer.
2.Why is it all in stereo?
To use it for 2 speakers like front left and right simultaniously.
3.How do I connect a mono subwoofer?
You connect INPUT with incoming stereo or mono signal. OUTPUT will be connected onto the subwoofer amplifier / amplifiers in stereo or mono.
4.How many power amplifiers can I connect?
Due to the high output voltage up to 10 volts you can connect 3-10 amplifiers with normal input sensitivity or 2-5 amplifiers with lower sensitivity.