henrik: My three bl1000s - all bought new from B&O
between 1997 and 2000 - all look like a mk1 on the flipside. Strange!
That's
odd since you bought them new - but the mechanical parts are all
interchangeable to my knowledge, so you really can't tell much for
certain from the rear shell if the remote is secondhand, and may have
been fixed / cosmetically improved via parts swapping.
The functional difference that divides between 1/2 and 3/4 (isn't there a Mk.5 as well?) is obvious from the button side:
- 1,2: RESET button, no up/down arrows
- 3->: up/down arrows and MENU, but no RESET
Internally, there are at least two types:
- contacts implemented with brass domes on a film
- contacts implemented with carbon contacts on a dome foil
I'm not sure where the divide is here - or if it even coincides with
the external differences - but I've seen both 1+2 with brass contacts,
later marks only with plastic dome foil.
Cosmetically, the later models have a semi-shiny top plate instead of dull gray.
To keep things interesting, the Mk.4 I have on the desk now only says
"Bang & Olufsen" on the front, while the others have "Beolink 1000"
as well.
There must also be some minor functional differences
with the seldom used commands... why would they have changed the rear
shell if everything else was the same otherwise.