Well, maybe but the difference is so small that it isn’t worth worrying about. If you have a local one to try then try it and see if you feel and hear a difference. Let’s say you hear a very small difference but that sax will cost you $14,000 and you can only get $8,000 for yours. is it worth this much more? Probably not, and you can improve your sound more with a high quality mouthpiece for under $1000!
all 6’s are better than most other horns so be glad that you have one, no matter what the serial # is. It’s true than some serial numbers will bring a higher price for different reasons but you’d have to be a long time and seasoned pro who is very fussy (and rich) to go around and do that.
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