Changing Key Heights

We had a customer in the repair shop this week who was interested in changing the key heights on her flute. Specifically, she wanted to lower the height of the French open hole keys.  We can understand how this could be an advantage from the perspective of the player's technique, but unfortunately, there was one reason it was not possible to lower the key heights.  What was it?  Venting.

Powell's Repair Technician, Rachel Baker, explained that keys have to open a specific amount in order to have the correct venting.  If she were to lower the keys, the flute would sound "stuffy," and there would be intonation issues because the keys would not have the proper venting.  Also, if one were to request having the key height increased, the result would be intonation issues as well since the keys would be too open. The venting and intonation problems that come from changing key heights beyond the proper measurement are not only for the keys that remain open on the flute. Rachel mentioned that in the past, she had a request to change the height of the G# key -- specifically, to change its height so that it would move less (of a distance) when pressed. The corresponding key cup (which is on the back of the flute) remains closed when the key is not in use.  However, once again, changing the key height would cause the key cup to not open enough when the key is pressed. So, the result would be venting and intonation problems.

There is one slight change that can be made, though.  Rachel said that for spatula keys, it is normally possible to change the angle slightly so that they are easier to reach.  Aside from this, key height is something that should stay in tact.  The heights are set to specific measurements so as to allow for proper venting and intonation.  With everything set properly, both you and your flute should be very happy!

The G Disc

It has several different names, but it all serves the same purpose -- the G disc, G donut, or high E facilitator.  Some flutes have a G disc, some have a split-E mechanism, and some flutes have neither.  We recently saw two Powell flutes in the repair shop with G discs that had different shapes.  The "donut" shape is an older style, and the "crescent" shape is the design that Powell switched to about 20 years ago.  The G disc helps facilitate the high E by limiting the amount of air that comes out of the tone hole -- because the key cup is open when you are playing the high E.  If you have a split-E mechanism, when it is engaged, the mechanism lowers the key cup slightly to help limit the amount of air coming out of the tone hole.  Reducing the amount of air coming through the tone hole via a G-disc or split-E mechanism is often times referred to as "venting" the high E.

As mentioned above, some flutes do not have any additional type of device or mechanism to facilitate the high E, because it is really a matter of the player's preference.  However, if one is in place, your flute would either have a G disc or a split-E mechanism -- not both.  If your flute does not have any type of high E facilitator and you are interested in getting a G disc put in, that is not a problem at all.  The repair shop at Powell can add one to your flute for roughly $70.  We realize there is debate on the G disc.  Many people find it very helpful in venting a high E.  In the case of intonation, some people find that it is an improvement, and others have the opposite view -- yet there are so many additional variables in what can effect intonation, so it all depends on the player and his/her equipment.  If you are interested in having a G disc installed, or if you have any additional questions, feel free to contact Rachel Baker in our repair shop at rbaker@powellflutes.com, and she'd be happy to help!

Red arrow points to older G disc design, yellow arrow points to current design.

Yellow arrow points to key that has a G disc in the tone hole.

With the G disc in place, the yellow arrow points to the open area of the tone hole.