Bass designs keep changing over time, so some signature models (like the Geddy Lee Jazz) are more about capturing the particular bass in that moment. I don't believe that he modified it too much other than a BA bridge. Yes, it's tied to an iconic player, but it's more or less a reissue.
Others are based on specifically modified basses played by a famous artist. I have owned the Tony Franklin fretless, and while I admire him as a player, I was mostly taken with how well designed and made the bass was. I still believe that the TF may be the best 4 string fretless out there.
Lastly, there are some basses that the manufacturer specifically creates for an artist. Lemmy's signature Ric looks like no other Ric I've ever seen. Similarly, I think that Tom Petersson and Adam Clayton must have created dozens of signatures basses with different manufacturers. Having an artist specifically tied to a special creation bass may help it to sell more. In the end, I tend to judge them on their own merits.
In the end, James Jamerson was the bass player who was arguably the best and definitely the most influential, and he just played a stock P bass with flats. Further, he preferred to have his action so high that it's unlikely anyone would want an exact replica. So, yeah, it's probably the player that's most important.
Others are based on specifically modified basses played by a famous artist. I have owned the Tony Franklin fretless, and while I admire him as a player, I was mostly taken with how well designed and made the bass was. I still believe that the TF may be the best 4 string fretless out there.
Lastly, there are some basses that the manufacturer specifically creates for an artist. Lemmy's signature Ric looks like no other Ric I've ever seen. Similarly, I think that Tom Petersson and Adam Clayton must have created dozens of signatures basses with different manufacturers. Having an artist specifically tied to a special creation bass may help it to sell more. In the end, I tend to judge them on their own merits.
In the end, James Jamerson was the bass player who was arguably the best and definitely the most influential, and he just played a stock P bass with flats. Further, he preferred to have his action so high that it's unlikely anyone would want an exact replica. So, yeah, it's probably the player that's most important.
