Alpha Angle?

[B. Scriver]

I get many e-mails asking what an alpha angle is so here goes.

The alpha angle is basically the first angle (alpha being the first letter of the Greek alphabet) of the mouthpiece wall as it falls into the cup. Some manufacturers call this "relief" or "undercut" but without defining the actual angle, this information is not really helpful.

To describe what an alpha angle is and does, I like to compare it to double doors that swing into a building. Open both doors the same amount but open them very little. You have to squeeze through to get into the building. This is a high alpha angle.
Swing those doors all the way open and 10 people can run through. This is a low alpha angle. What does this mean to trumpet players?

The correct alpha angle for you can support your chops in your natural playing position. It will assist in holding the chops in a natural equilibrium for you. Attacks will be crisp, sound will be full and fluid, range will not be hindered.
This is critical depending upon the amount of lip engagement you have into the cup. Alpha angle is player specific!

If that alpha angle is too high for you, then you may bottom out, blow resistance will be too high as the chops are help too tightly closed, attacks will be hindered, sound will be scratchy.
If the alpha angle is too low, the chops will be allowed to protrude too far into the cup in too opened a position. Attacks will be blatty and sluggish, sound will suffer, range and endurance will be hindered.

We have some playing tests to help determine correct alpha angle. E-mail me if you need some assistance in this area. We have been working on a new GR website and alpha angle info will be on it with some diagrams as well.

Every mouthpiece has an alpha angle. GR is just the first to define it in terms of degrees. This will help in finding the correct mouthpiece for you.

Please feel free to contact me if you have any questions or if I have left anything out. You may also feel free to contact Bruce Lee at http://www.northernbrass.com

Thanks! Bri

Brian Scriver
http://www.brianscriver.com
http://www.grmouthpieces.com

[2LIP]

Bri:

I have heard this refered to as "bite" by other MP guys. Is that the same thing?

The LIP

[drunkiq]

also i see some refer to the top cup as being part of the bite/alpha angle - this has always really sounded like three diffferent parts to me and I think you above post is telling me this but i have to ask a littlle more -

Alll I know is that when I have a mpc made, I call Schilke - tell them to grab a 13a4a, then use the same bite (actually mine is modified, so they have to copy mine), then to keep the same TOP cup, so it all fells the same to me on te front end...

Then they can do what ever to the bottom cup... I usually end up picking the backbore - depending on the use and resistance/horn it will be used on, but have never messed with the throat of he 13a4a...

comments? I am getting this right from your prespective?

Thanks!!!!
_________________
-Marc
A Schilke Loyalist
drunkiq@hotmail.com

My Schilke X3Lb in Satin Gold
[img]http://us.f2.yahoofs.com/users/3f4577e3_1283/bc/X/__hr_x.jpg?BCoZaR_ARis3g4PD[/img]

[Castle Bravo]

At the very top, you will see the "a" angle....

[GR Tech]

Thank you Mr. Wilder for posting the drawing of the GR Parameters. I will attempt to explain the Alpha angle in technical terms most people should be able to understand.

The "Alpha Angle" is not the bite (Rb), although, it can affect how the bite is perceived by the player. I will attempt to define this below.

The "Alpha Angle" is the "First Angle" in the mouthpiece. It may also be called the "Rim Angle". This angle defines the relationship of the "Bite Radius" (Rb) to the "1st Cup Radius" (R1). The "Alpha Angle" is a line that is tangent from the "Bite Radius" (Rb) to the "1st Cup Radius" (L1).

To find the alpha angle start at the top parameter (ro or highpoint) and follow the dark curved arc to the left. Follow the dark curved arc until you reach point (r1). At (r1) the "Bite Radius" (Rb) begins. Follow the dark curved arc until you reach point (r2). At (r2) the "Bite Radius" (Rb) ends and intersects the "Alpha Angle". Now follow the "Alpha Angle" to point (r5). Points (r2) to (r5) is a line ("Alpha Angle") that represents the relationship of the "Bite Radius" (Rb) to the "1st Cup Radius" (R1) in degrees. This line ("Alpha Angle") is tangent to the two arcs (Rb & R1). The length of the "Alpha Angle" is a parameter called the "Relief" (L1) and is given a length. The length of (L1) may be zero, then points (r2) and (r5) would be the same. Continue to follow the dark curve at point (r5) the "1st Cup Radius (R1) begins and ends at point (r6). The "Beta Angle" (L2) begins at (r6) and ends at (r7).

We have digitized 1000's of mouthpieces and assigned parameters to them. The lowest alpha angles are about 5 degrees (Monette B 1-1) and highest about 40 degrees (an old Maynard Mouthpiece). Most people can not play on the extremes with success. This is due to statistics and the population curve. Most people will be closer to the middle of the Bell Curve. While these extremes work for some they will not work for most. From our experience 9 degrees is about the lowest practical alpha angle, although, a few people can tolerate lower. On the high side 20 degrees is about the limit, although, people using embouchures that feature the upper register have been able to tolerate angles to 30 degrees and more. Here are a few common "Alpha Angles" of common mouthpieces. Due to manufacturing consistency these may vary a degree or two with certain manufactures. Just to give you an idea here are a few common mouthpieces 3C 15 to 16 degrees, 1X between 9 and 10, 1C 13 to 14, 1 1/4C 16 to 17, 6A4a 24 to 25, 13A4a 24 to 25, and DT-10 27 to 29. Please don't contact us and ask for these numbers, we do not give them out as it took over 10 years to accumulate, data base, and define them.
_________________
GR Tech