entschwindet wrote:Means you can play Dowland etc in the right key.
Sorry, but that's not quite the case. We have no idea of the string length Dowland used for any given piece, and therefore we don't know what the pitch was, and therefore we don't know the key. There was a "nominal" pitch of g for the first string, but in reality it could have been a tone higher, or as low as an Eb for the first string. There is nothing in the tablature to indicate pitch or key.
And then there is temperament...
Best abandon any pretence at doing anything historical when it comes to the modern guitar, eight strings or otherwise.
My 8-string guitar video is in a fairly obscure tuning known in the 17th century as Harp Sharp, but I was playing from the lute tabs for that tuning. I only had the guitar for a week before selling it. Nothing can rival a lute for lute music.
On the other hand, I love the compositions for the ten-string guitar, Yepes' tuning. I'm sure they would sound awful on a lute!