Back in the early '80s, that Tandberg was
legit. 100 wpc and retail approaching 2000 DM around these parts, definitely no joke. (It might appreciate a minor overhaul to clean contacts and replace the odd capacitor, but that's about it.) The speakers are nothing to sneeze at either:
...although from a modern perspective, I can see some potential issues:
1. Nobody would be placing the midrange and tweeter horizontally next to each other any more - horizontal dispersion irregularities are a good bit more critical than vertical ones, and while driver spacing seems decently low and crossover at 3 kHz isn't overly high, I'm still not convinced. First order of business for me would be
pulling a monitor and rotating them by +/-90°, using stands of sorts for the proper height if necessary. I would say tweeters facing out, even if that means one side has the tweeter up and the other down - things will never be 100% symmetrical. This'll take some experimentation.
2. Speakers like this have
very wide dispersion. I hope your listening room exudes all the plush charm of the time, with plenty of carpets, curtains / drapes, sofas and other furniture. A modern "architect's dream" hellscape with hard flooring, empty walls and tons of window area would be the worst kind of place to put these into.
3. Also, I wonder what kind of level handling a 2" dome crossed over at 500 Hz has.
Instead of looking at
vacuum bulb nonsense, I'd be putting my hard-earned pennies towards things that make a
real, tangible improvement. For example, that Tandberg no doubt has a tape loop - why not use it to include a DSP unit for room correction, like a miniDSP Flex or at least a 2x4HD (as a modern take on the classic equalizer)? And a measurement microphone (either as USB or XLR with an audio interface)? Any room screws up the bass to some degree, which should be just as obvious to old ears as to younger ones. We have the tools to do something about it now.
Some details on room, listening position, source devices in use and the like would definitely be useful. You can do "hi-fi" in totally different ways nowadays. Some folks have their music on a NAS and are using a streamer... combine one of those with active speakers, and there's precious little left of the classic device stack. You can have nice sound on the computer or a nice headphone setup on the bedside table.
Also, I hope you aren't listening to all the same music you did 30-40 years ago... and a collection that isn't well in the hundreds if not the thousands probably has room for expansion left. This is what we're doing all this for, right?
this phenomenon is called genericization. 
