The dimensions and taper of the neck are essential, model specific design parameters for any saxophone, just as tone hole size and tone hole placement are, the primary concern of which is to insure harmonicity of the tube resonances - to keep the harmonics in tune in order to obtain all of the following:I actually play tested the neck for 2 hours then purchased it. I was very impressed with the sound & feel of the product. The issue I had was that I could not keep it in tune. The intonation would change + & - on any give note, at any given time.
1. optimal tone quality at all dynamic levels
2. optimal dynamic range and response,
3. optimal intonation and stability at all dynamic levels
It's just a fact of wind instrument acoustics - The better the resonances are aligned, the better everything will be.
Throughout the history of the development of our conical wind instruments, various alterations to the basic conical bore (multiple tapers, sudden diameter changes) have been introduced. The applications of these bore irregularities which are still with us today, are all model/design specific and their primary purpose is to improve intonation.
Unquestionably, altering the diameter, shape, and taper of the first 1.5" of the neck is an extremely effective way to alter the tone quality and response characteristics of any horn. Unfortunately, it is equally effective at increasing the inharmonicity (the degree of harmonic misalignment) of it's overall acoustic design. If the horn specific, initial design parameters (volume/Frs) are not somehow restored by compensating changes in mouthpiece chamber size and design, then one can only expect the intonation to become unstable and uneven to some degree, as in the above case. Is the gain worth the pain?
Acousticians like Arthur Benade, would advise leaving the original neck design unaltered and exploring the other, less alignment altering means of tone/response shaping - mouthpiece design. For the player though, I think it can only be determined on an individual player/horn/mouthpiece basis.