I've seen a few photos of this 6 stringer over the years, which is definitely DB scale, but also is 300+ years old: Invalid Link Removed
I haven't seen one this big with seven strings, just the smaller gamba size ones. There are plans available from that museum for a smallish 6 stringer and photos of a seven stringer in the same size category. I'm hoping that band, I can't recall the name, will show up at the 5-Spot again and I can get a look the modern version.
I have to agree with you on the 4-stringer, Ken. People used to ask when I was buying a new bass and my answer would be, "After I learn to play this one." 30 years later, that is still my only electric bass. I still think I haven't exhausted the possibilities on it, but I'm at an age where now, I just want to be more adventurous anyway, the goal of virtuosity having succumbed to the goal of having fun. On the DB side I now have the 5-stringer and have decided more strings isn't so hard to get used to. It is difficult to find exercise material that uses the lower string though so I've been transposing things down a string.
You (Ken S.) built a 6 stringer back in '81 or before that was sort of a ground breaker for EBGs if my memory serves me. I'm just wondering who is building these new 7-string DBs, and what they sound like. I know the theory goes that the more strings, the less projection, etc., but that turned out not to be the case with my fiver, so maybe these new sevens aren't far off the mark on sound either.
I'll see if there's a way to get into the Bass Player back issues and search. Bassteban, if you come up with anything solid (oops, I mean hollow) on that photo, please post a link.