Do not try this at home!
Unless you are technically adept and knowledgeable. This is a totally necessary disclaimer!
Ever since I had a WW repair class at Northern Michigan University, my undergrad school, I have tinkered with my flutes. That includes repadding, reshimming, adjusting the height of the keys, undercutting and overcutting the blow hole, and fraizing the tone holes. I am now also revoicing my baroque flute.
Based upon my experience, once you have a new flute and you want it to play as well as possible, there are a few things you can check to make sure that it plays at an optimal level.
One of the most important elements to consider is the height of the keys above the tone holes. Having the keys too high can make the sound too resonant all the time without the ability to change tone colors. It can also make the upper register notes too sharp in relation to the lower registers forcing the flutist to pull the head joint out too far. Pulling the head joint out too far dulls the sound and makes it difficult for the flutist to play with an open throat. It also causes decreased agility in the upper register.
Some experts believe that lowering the keys is detrimental to the sound and intonation of the flute. However, it is easy enough to add additional thicknesses of paper to the felts to lower the keys to gauge the effect. If the keys are too low, the sound of the flute is noticeable stuffy and a general lowering of the pitch can occur.
Once the keys are at an optimal height, there should be a feeling of increased resistance to the air stream. Especially in the upper register – which should be lower pitch-wise with relation to the lower octaves and should be generally more stable. After the keys are at an optimal height, the flute can be re-felted or re-corked. A decent repair person should be able to do this without difficulty, although some repair people are reluctant to do it.
Often, the flutist whose flute has overly high keys will experience a loss of support while playing – essentially the flutist’s body will collapse around the air making thoraco-abdominal support difficult, if not impossible, to achieve. Once the position of the keys is corrected, the flutist should be able to support correctly after a fairly short amount of time – one to two weeks, typically.
I had one student whose repair person refused to lower the keys after I had diagnosed that the student was having sound production problems as a result of the keys being too high. I went ahead and lowered them myself, and within a week or so, my student was back up to snuff.
Even the best flutes can have this problem. One of my students recently purchased a really great Nagahara flute – the 95% silver, 5% platinum alloy. It is truly a work of art! However, the keys were a bit too high. My student’s 14K gold Brannen flute had lower keys and, partially as a result of having lower keys heights, played better. The key height on the Brannen matched the adjusted key heights on my Jupiter 1011. The flute was sent back to Nagahara, who gladly fixed the problem after which the flute played better.
Another consideration on a new flute is the spring tension. A relaxed tension makes life a lot easier, especially with difficult passage work. The spring tension on the aforementioned Nagahara was a bit stiff, but the factory adjusted it upon request and, boy, is that a nice flute! Especially with a less muscular action. 🙂
Finally, we get to the dreaded Powell Pop.
What, the dreaded Powell Pop? Never heard of it? That’s the moniker that I’ve given to the phenomenon whereby notes in legato passages have a distinguishing starting accent. In extreme cases this sounds like each note pops out. This effect can usually be alleviated somewhat through proper support, but there is a mechanical basis for this peculiarity that sometimes cannot be overcome.
So what causes the Powell Pop? Oddly enough, this phenomenon is caused simply by having sharp edges on the tone holes in the tube of the flute! This is especially true of flutes with soldered tone holes – such as the traditional hand-made Powell. Emma, one of my great students, was working up a piece for flute and organ for a concert. One of the few recordings of the piece was a performance on a vintage Powell flute from the 20’s or 30’s, I believe. The legato passages were all marked by the signature “popping” quality. Perhaps endearing to some, this sound can verge on the extra-musical to the point of being a tad bit obnoxious.
The means to alleviate this is simply through fraizing or undercutting the tone holes. A well qualified repair person can do this for you, if you can convince him or her of the necessity of doing it. 🙂 As this is a destructive process, you may want to find the most qualified repair person to do this.
The benefits of tone hole fraizing are an increased smoothness going from note to note in legato passages and also increased smoothness in making skips and leaps, especially in the upper register.
Now here’s the part where I have to repeat the disclaimer – DO NOT TRY THIS AT HOME!
I was once told by a flute repair person that instead of more destructive filing, one can fraize the underside of tone holes with just a silver polishing cloth on the flute cleaning rod (for the larger holes). Also, this unnamed source told me that just the leading and trailing edges need to be smoothed to achieve the desired effect.
Tinker that I am, I tried this method of tone hole fraizing and found that it works quite well and is not terribly destructive.
But, unless you are technically adept and knowledgeable, DO NOT TRY THIS AT HOME!
A further caveat would be to try any possibly destructive operations on a junker flute first.