Quote:
Originally Posted by Chrisk-K  Deadspots occur because resonant frequencies of neck wood are close to a few notes on the bass. |
That makes sense; having owned several basses of varying pedigree, as it were, I'm not sure that a $3,000 bass is necessarily less prone to dead spots than is a $400 bass. The resonance of the neck is affected by headstock mass and the ratio of neck to body mass, as well as other factors, such as truss rod adjustments.
Rick 4001/4003s are prone to a dead spot on the 9th-10th fret on the D string. Fender basses (perhaps P's more than J's, although my reasearch sample isn't big enough to state that conclusively) are prone to dead spots on the G string between the 4th and 8th frets). My Warwick has a dead spot on the 7th fret E on the G string.
Dead spots do not manifest themselves as a lack of volume; they manifest themselves in a noticeable lack of sustain; much like a noise gate cutting in early.
I was able to almost completely remove the deadspot on my Rick 4003 by chanding over to lightweight tuners. Others have been able to remove or greatly reduce the dead spot(s) by tweaking the dual rods to move the resonance spot to a position unaffected by the fingering position relative to the frets.
My Warwick is not dead spot-free because I switched to 'cello tuning and it just went away.
So, to answer the OP's question, if a high-end builder takes into account relative mass of the headstock to the body and takes steps to reduce the dead spot, then yes, it makes a difference. Oddly, it strikes me that a more mass-produced manufacturer would have the liquid cash to resort to that sort of research project on a build design.
But, in the end, it seems that few builders, large or small, have advertised this sort of research to combat what is a certain problem with many basses.
/end ramble.
Handmade = no deadspots? 
