Bass Head tube (12AX7 preamp - Power ECLL800) dating from 60.
Ad power but delivers 10W 100 (the magic of Swedish Watts?)
2 settings: volume and filter (tone) ample.
2 input jacks for instruments.
1 output jack to the speakers: it is the only inconvenience, it delivers only of 16 ohms and no less
What configuration?: 2 buttons, 1 volume and the filter will be set once never changed.
What manual: it's all in Swedish!
Sound: I thought my old Bassman rehear 135! It's hot, it's good, it's lights.
It's vintage and it does not like active basses but otherwise, everything is possible (even metal minimalist, given its 10W!).
Besides the active basses, all low (even a cake server) without sound problem but it has its own personality. This is not Markbass or EAR Super Straight.
I put a little time to find a lamp-type power ECLL800 in good condition but it is yet.
Since then, I sold my Hartke, H & K, Ampeg and uses only repeating and components.
I would not use it in concert (and no exit 10W toward mixing desk or other), but with its look of toaster 50 years, he will stay with me.
Good luck finding another one elsewhere than in Sweden (and again) but the miracle of flea markets is still operating. That's where I found it.