I'll resurrect this thread rather than start a new one. I got an Elf as a backup amp, but thought I would test it at a rehearsal. We play at pretty much gig volumes. I used it though a GR bass AT212 slim. I had to turn it down a bit, ended up about 2 o'clock gain, 9 o'clock master volume. All tone knobs about 1 o'clock Turned up to 3 o'clock it was very loud, enough for any gig I've done, louder and it started to distort unpleasantly. Definitely much louder than my Laney 150W, but not as loud as the Bass Terror.
Very happy with it, but the cheap Stagg jack to speakon lead turns out to have a jack plug 2mm too short that vibrated out of the socket if the amp was on the speaker.