Sounds like the bass is coming along; I'm looking forward to seeing it completed.
I missed the initial discussion, but on the subject of the D vs. Eb neck - personally I can go either way; I think that because of the "standardness" and construction aspects the "D" neck is understandable. But - in terms of which one I'd rather play, aside from the fact that I find it annoying switching between the two, I'd rather play the Eb neck and were I to have a bass made (that was to be my primary instrument) I'd want it made that way.
That said, I also have no objection to a longer string length; granted, I'm a fairly large guy with bigger hands and a flexible technique, but I really feel that the shorter string lengths we shoot for today are often a crutch (among several) keeping players from developing technique that would allow them to play a longer length without trouble. Sure, a shorter string length is functional and feels "easier" to play, but I don't think that in terms of tonal precision they stand up and that given the same bass and same player, assuming good technique, there is more potential for a tonally "clear" performance with a longer string length.
There's a reason there is only one row of guys playing bass in the orchestra - not everybody is able or willing to do it - we don't need to compromise the instrument so everyone can play it...
(yes, I know there are other reasons too.
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