Accessories Tuner Screw Neck

[Ivan]

Prompted by Ad's thread about C Melody saxes with a link to a Thomann C Melody that has a tuner screw neck my question is:

Why?

Wot's wrong with moving the mouthpiece over the cork?

 

[jbtsax]

My understanding of the theory behind this is that once the mouthpiece is set in the optimum position on the cork to have its "effective volume" match that of the missing cone, then the "micro tuner" can be adjusted to bring the pitch of the instrument to A=440 by changing its length without upsetting the mouthpiece volume.

 

[Ivan]

My understanding of the theory behind this is that once the mouthpiece is set in the optimum position on the cork to have its "effective volume" match that of the missing cone, then the "micro tuner" can be adjusted to bring the pitch of the instrument to A=440 by changing its length without upsetting the mouthpiece volume.

But does it work I wonder?

 

[kevgermany]

But does it work I wonder?

Me too. What, acoustically, determines mouthpiece volume? Where does the neck end and the chamber start?

My guess is that apart from being a sales gimmick, it may help to make tuning easier/quicker as you can tune while you're playing.

 

[jonf]

Whatever the theory (and I think jbtsax is right on the theory) the fact that none of the major manufacturers use it makes it pretty clear it's not needed. I think the Thomann branded Chinese C Mel only uses it as they have copied faithfully the original 1920s Conn design, from which it came.

 

[jbtsax]

Me too. What, acoustically, determines mouthpiece volume? Where does the neck end and the chamber start? My guess is that apart from being a sales gimmick, it may help to make tuning easier/quicker as you can tune while you're playing.

The neck ends at its opening and that is where the mouthpiece chamber begins. It's that simple.

If you put tape over the lay of the mouthpiece and fill it with water which you then measure with a graduated cylinder, you can effectively determine the "geometric volume" of the inside of the mouthpiece. The "effective volume" of the mouthpiece when it is actually being played is the sum of the "geometric volume" plus the volume added by the elasticity of the reed, and the contributions to the volume by the "oscillatory effect" discovered by Helmholtz (something I don't yet understand). This "effective volume" can also be changed to some extent by the player by tightening and loosening the embouchure and I believe by changing the "voicing" inside the oral cavity---although I have nothing to back up this last assumption.

In Fundamentals of Musical Acoustics p. 466 Benade shows a chart comparing the "geometric volume" of a soprano sax mouthpiece to its "equivalent volume". On an average the "effective volume" was found to be approximately 33% larger than the "geometric volume". Doing a measurement using the same techniques as Benade and Gebler on my Rousseau alto mouthpiece, I obtained a similar result. It is this "effective volume" that must closely match the volume of the missing cone in order for the instrument to play its best.

I was hoping that the original patent for the "microtuner neck" would have a reference to the advantage of not changing the volume of the chamber of the mouthpiece, but it makes no mention of such.

Patent US 1308903

I believe the reason the microtuner was dropped, was because of the expense, not because it was not useful. If I ever get a Conn with a microtuner it would be easy to test the intonation of different registers by tuning the sax both ways and comparing the results.

 

[kevgermany]

I've always found this bit of theory dodgy/simplistic. To me part of the shank/neck form part of the chamber. But it's moot. What we have is good enough.

 

[jbtsax]

I also think that the area inside the shank of the mouthpiece that extends beyond the end of the neck is part of the "chamber". In any event it contributes to the "geometric volume" inside the mouthpiece.

 

[altissimo]

here's a bit more info on Conn microtuners - http://cderksen.home.xs4all.nl/images/Art50-ConnSaxophoneMicrotuner.pdf
http://www.shwoodwind.co.uk/HandyHints/ConnMicrotuner.htm

unless the theory of 'effective volume' of the mouthpiece was around in 1919 when the Conn microtuner was patented, it would seem unlikely that the purpose of the device was as suggested by jbt.
Arthur Benade wasn't born until 1925, so it's unlikely his research could've had any influence on Conn's engineers

 

[Ivan]

here's a bit more info on Conn microtuners -
http://www.shwoodwind.co.uk/HandyHints/ConnMicrotuner.htm

That article by Steve Howard certainly illustrates the problems of maintenance that can occur and doesn't exactly endorse the technology

Also the microtuner's sliding tube within a tube, both of which are presumably cylindrical, are not the usual continuous cone that is a sax neck in direct contravention of many firmly held beliefs expressed on this site about sax acoustics

 

[altissimo]

That article by Steve Howard certainly illustrates the problems of maintenance that can occur and doesn't exactly endorse the technology

Also the microtuner's sliding tube within a tube, both of which are presumably cylindrical, are not the usual continuous cone that is a sax neck in direct contravention of many firmly held beliefs expressed on this site about sax acoustics

if you read the other link - "First is a thin-walled cylindrical brass tube which telescopes snugly into the bore of the receiver, Second is an annular flange with a larger external diameter than the receiver. Third is a conical (tapered) tube (referred to as the mouthpipe) which is covered with a thin layer of cork to accept the mouthpiece"

I've got a Conn alto and a C melody with microtuners and I never use that part of the mechanism. I can see no reason why this chinese company are making C Melody saxes with microtuners, it's just a waste of effort..
If there's any demand for microtuner equipped instruments, it's only vintage Conn's and even then microtuners (and rolled tone holes) are more an indicator of a particular era when Conn craftsmanship may have been at it's height more than them having any practical value - It's only a coincidence that the most desirable Conn altos have the microtuner. Conn discontinued these features in the late 40's/early 50's as a cost cutting measure.
As far as I can tell, Conn never fitting this device to tenor saxes, only alto and C melody.

 

[jbtsax]

unless the theory of 'effective volume' of the mouthpiece was around in 1919 when the Conn microtuner was patented, it would seem unlikely that the purpose of the device was as suggested by jbt. Arthur Benade wasn't born until 1925, so it's unlikely his research could've had any influence on Conn's engineers

You are correct in the times and dates. However, I strongly suspect Antoine (Adolph) Sax was aware of the importance of the mouthpiece having the correct interior volume in order for his "conical brass woodwind" to play in tune with itself. The mouthpieces he created were shorter and had much larger chambers than modern mouthpieces---something Sigurd Rascher tried to imitate with the Caravan pieces he played.

Also the microtuner's sliding tube within a tube, both of which are presumably cylindrical, are not the usual continuous cone that is a sax neck in direct contravention of many firmly held beliefs expressed on this site about sax acoustics

In reality most saxophone necks are very nearly cylindrical the last 50 millimeters where the neck cork goes, and of course the neck tenon is perfectly cylindrical except in a few rare cases. On the necks I have measured the taper in between those two sections is fairly consistent. It is open to debate which taper to use to calculate the length and volume of the "missing cone"---the average taper of the neck, or the taper of the body. I have had good results in using the taper of the neck as described in the book "The Saxophone is my Voice" by Ernest Ferron.

 

[Ivan]

In reality most saxophone necks are very nearly cylindrical the last 50 millimeters where the neck cork goes, and of course the neck tenon is perfectly cylindrical except in a few rare cases.

Thanks as ever jstsax for your expert view

Out of interest does using millimeters cause you physical pain seeing as you're located in the land of US weights and measures

 

[jbtsax]

Since I have a "scientific" mind, I would love it if the U.S. would go to the far superior metric system---at least for linear measurements. Liters still throw me off since I grew up using cups, quarts, and gallons.