Hi Brian,
I'm using both. Well that is, I have both the F-1X and F-2b as well as the SF-2. On stage I prefer the F-1X with the SF-2 in the effectloop.
I use my Series I in mono. I'm used the a full range sound behind me. I did use it in stereo once but just because a lot of stages are to small to hear a good mix from both cabs, I prefer the full range through both cabinets. Besides that I really do like the XLR out on the F-1X. No external DI boxes, switches, mics, cables or whatever. Just plug it in to the mixer. Easy, silent and always working. It also has a crossover which can be used with two mono or one stereo amp. But you already know that.
This is how it's connected. Bass to DS-5 mono out to F-1X in. Effectloop send to SF-2 channel A in. Channel A patchcable to channel B in. Channel B to effectloop return. SF-2 in mono. Great. The only thing I dislike is the power on/off at the back. But, why use it anyway.
For me, the SF-2 plus F-1X are the right combination. I sold my SF-2 last year but bought one back. Most stupid thing to do is sell that little wonder. I bought it when I was using a signature Alembic EVH bass. i didn't know what to expect when connecting the series I. If you ever meet somebody with a smile from ear to ear (or maybe to the back of his head), it's probably me.
Michael, the deep switch clears your sound. in the one sheet manual it says it clears a muddy bass sound. The bright switch is what is says. Bright. And I mean bright bright.
Paul, try the SF-2 with you SWR first. I had problems with adding the SF-2 to another amp.
My amp was a bit noisy. I never noticed that but when I added the SF-2 I could hear all the noise and hiss that was already in that amp. It all came out. The SF-2 is very silent but if you choose a frequency that's the same as the noise or hiss in your amp you will hear it very loud. It's better to combine with a separate pre-amp and poweramp than a, how do you call these things, everything in one box amp. Or whatever.
Because you live in belgium, have a look at
www.hevos.nl I'm using his cabs but he also builds 800 and 1600 W poweramps. The speakers are great by the way. 400W each. A 4x10 can handle 1600W. You don't need it, but you always have a clean sound. He's located in Limburg near Venlo.
Manfred