Flute/Audio Geek Question

So, looking through spectral analysis of my different flutes, I notice a strange dip around 10K on my alto flute. It’s as if someone ran a notch filter right at that frequency. (It’s an alto with a straight headjoint, not a curved one.) Here are the examples. They are raw, not processed, all recorded on the same microphone and digital recorder.

This shows an example of my alto flute playing in a small room. It looks like a notch filter around 10K:

The next shows the same the alto flute, same music, same equipment, in a different room. The same dip around 10K and here the bulge just under it is more visible. (This one has the view up to 20K.)

For comparison, here is an example of my bass flute playing, same equipment, same room as the previous example:

And for another comparison, here is my C flute sound, same equipment, same room as the previous 2 examples:

Does anybody know what is going on? Any alto flute makers of headjoints know if this is something typical? Any alto flute players want to compare?

[Edit: I received an answer on Facebook from Dave Gedosh suggesting that it has to do with the construction of the flute. Then I received an email from a reliable source that gave this explanation:

I have a theory that the notch you see may be due to the natural resonance of the flute type you are playing due to diameter of the flute.

Not knowing room temp nor altitude I predicted various notches for various flutes in a linear fashion based on your observed notch .

Alto flute length 34”, 1” diameter, wavelength 13khz @ 20 deg c, sea level Seen at At 10 kHz

C flute length 26 1/2” ,3/4” diameter 18khz @ 20 deg c , sea level Predict 14 kHz

To check this, I take the same C flute example as above, but shown up to 20K and with one channel zoomed in. There are dips around 12K and 9K. Maybe because of the B foot? Cologne is about 37 Meters above sea level, and it was about 20°C.

Bass flute length 52” ,1 3/4” diameter 7.72 kHz Predict 6 kHz  Note bass flute notch is lower (allowing a lower range ? 🙂 ) {edit: is the curvature of the headjoint taken into account here?}

Maybe I am wrong but the coincidence of the wavelength and the flute diameter seems too much to ignore.]



“Music is Love” – Anthony Braxton

Lately I have been more interested in creating and producing sounds than words. It has been difficult to distill my experiences of the last season in to words, so I have not been blogging. Over this blastedly hot summer “vacation”, I decided to take only Anthony Braxton’s Composition no. 133 with me to practice. Having re-visited Stockhausen’s PARADIES in May, I was eager to work on a piece that has a similar concept, that of given material in strophes where the performer has a certain amount of freedom to shape the material. Braxton’s piece allows for much more freedom than Stockhausen’s, but does not include an electronic track. But then I thought, why should it not include an electronic backing? And the thought snowballed.

There are not enough really excellent pieces for flute and fixed media, in my opinion, and even fewer that include improvisation or some sort of freedom for the performer. It seems that a lot of really experiment-oriented composers are writing for live electronics and processing. Which is really cool! But for those of us performers who want an easy set-up of solo work, some speakers and a microphone that we can play in simple venues such as clubs or art galleries where there are no technicians and only a small budget, I for one would welcome some really good new works for fixed media that include some sort of side-stepping from the fixed-composed tradition.

I’ll tell you why I think this departure from fixed composition is important at this point in time. Almost every piece that I hear for flute and fixed media is using the same flute sounds (and in some cases, electronic sounds) that have been around since the 1980s! It is time to find some different sounds. No wonder composers seem more interested in live processing flute sounds. But I don’t want the world to give up on fixed media yet because of the practicalities mentioned above, and its potential awesomeness!

I have several unhatched plans to remedy this situation which include collaboration with several artists willing to include improvisation or elements thereof in their pieces. I have been working on creating compositions of my own (not for Braxton’s piece though, I have decided to leave that alone). The learning curve has been quite steep but I am loving delving in to the world of sampling, granulation, processing, etc. So back to creating sounds instead of words 🙂

Photo credit: Hans Peter Schaefer


Some Practice Ideas

A few thoughts after some days of intensive practice. My focus has been awareness of tension, since I have a few sore points on my hands due to an old injury. One concept from yoga has helped me. According to what I have learned, the arm structure is considered an open system, whereas the legs are a closed system due to the fact that they end with the feet on the ground (at least when standing). In flute playing, the arms are also sort of closed system; they end with the fingers on the flute. But I like to imagine that in spite of that, they are open systems. Just that feeling that they could continue to extend if they wanted. Same with the legs while performing, even though they are grounded, I like the idea of them being an entire structure that could extend if needed.

It is very important for me to think of extension not only as motion away, but with a twist. Pretend you have a knob that’s straight in front of you and just beyond your reach. Bring your right arm out to reach for the knob. Bring your shoulder blade from the back with you while reaching out, but make sure the shoulders are not raised. Rotate the entire arm outwards (as if you want to turn the knob to the right with your whole arm).  Then, leaving your upper arm (the part nearest the shoulder above the elbow) as is, rotate only the lower arm and your palms in (as if turning that knob back to the left). Then bring the arm into playing position (let the shoulder blade come back with the arm). When I do this, I have a better feeling of security and freedom. Repeat with the left arm, first turning the knob to the left with the entire arm, then back to the right with only the lower arm.

The other thing I have to tell myself is not to get tense about tension. If at the end of a phrase I notice my leg is stiff, so what? Just unstiffen it and get on with it. The point is, I noticed it. I have to remind myself this is a process. If there is time, repeat the passage with better awareness, to find out which action made me try to support with my leg. And then hopefully laugh at my ridiculous notion that a locked knee can help with my high note. Better than beating yourself up.

And Mula bandha really helps! (It is NOT the squeezing of those other cheeks that some refer to.) Awareness of the pelvic floor is a positive way to exercise awareness, to get away from being too vigilant about the negative or unproductive things. I once had a male flutist tell me “but I don’t have a pelvic floor” and I was gullible enough for a microsecond to actually look down to see if his insides had spilled out onto the ground from between his legs. Guys, you do have pelvic floors. It is part of the blueprint for human anatomy.