Lots of interesting splinter threads could come off here Jacqueline...!

On the "first Austio-Bavarian cradle trek Southwards and/or west" that
is just a supposition, and quite an old one too - some modern scholars
now suggest that there was no "trek" or movement, that these ancient
cultures on the fringe of Europe are the oldest and have developed
right where they are now for the last 7000 years, since the Ice
retreated. Barry Cunliffe's book "Facing the Ocean" is a must-read if
youre interested in these issues.
http://www.oup.co.uk/academic/humanities/classical_studies/viewpoint/
barry_cunliffe/

Keith, there are lots of suppositions in what you say. For a start,
when these first illustrations and words appear in the sources between
say 600 and 1000 AD we are NOT seeing the invention or introduction of
a tradition, merely the first glimpses of it in action. I think that is
the problem with that chapter in "tree of strings" - they confuse
appearance of the evidence with evidence of appearance.

Secondly, I do not think there is a connection between harp and lyre.
They are completely different instruments. I think of a lyre as a
complex developed instrument very similar to a violin, in its use of
bridge, tailpiece, endpiece, peg-holder, flat soundbox etc. My theory
which I have to say comes from the same complete lack of evidence as
yours, is that the metal-strung harp evolved in the North-Western
Seaboard of Europe during the Bronze Age (perhaps 1000BC) - perhaps a
simple angle or arch harp like modern African examples? And gradually
evolved into the solid triangular 30 string monster we know and love.
The lyre meanwhile was a classical Greek/Roman innovation that came
into the North West around 100BC or so, as an exotic, classicising high
status item. Just my speculation though.

Again, to get a real sense of why a lyre is not just a simple type of
harp, but a completely different much more developed instrument, see
Bob Evans's video at
http://www.bragod.com/3nweur.html

So you'll see that any statement about the origin of the harp, or where
it came from, or which string material came first, is complete
conjecture, and tells us much more about the person doing the
conjecture than the historical situation.

Although Curry is useful for presenting these unavailable texts his
translations and interpretations can often be seriously misleading.

Simon