lengthening an instrument a tiny bit changes the scale

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ttf_timothy42b
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lengthening an instrument a tiny bit changes the scale

Post by ttf_timothy42b » Thu Jan 18, 2018 1:25 pm

I was playing an alto recorder along with a youtube video (I play for the Christmas pageant every year, so I get it out and practice a bit).

The video pitch was a tiny bit lower.  So I pulled the alto apart just slightly at the headjoint.  Maybe an eighth inch - certainly less than 1/4. 

This dramatically affected the pitch of most of the notes in the scale.  I actually could no longer play it.  It did not move them uniformly up or down, but spread them out so they sounded like wrong fingerings.

Has anybody else noticed that?
ttf_Andrew Meronek
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lengthening an instrument a tiny bit changes the scale

Post by ttf_Andrew Meronek » Thu Jan 18, 2018 2:10 pm

Makes sense, especially on a shorter instrument like a recorder. It wouldn't take much to change the relative position of the finger holes compared to the length of the instrument, and that's not even considering antinodes.
ttf_watermailonman
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lengthening an instrument a tiny bit changes the scale

Post by ttf_watermailonman » Thu Jan 18, 2018 2:16 pm

Quote from: timothy42b on Jan 18, 2018, 01:25PMI was playing an alto recorder along with a youtube video (I play for the Christmas pageant every year, so I get it out and practice a bit).

The video pitch was a tiny bit lower.  So I pulled the alto apart just slightly at the headjoint.  Maybe an eighth inch - certainly less than 1/4. 

This dramatically affected the pitch of most of the notes in the scale.  I actually could no longer play it.  It did not move them uniformly up or down, but spread them out so they sounded like wrong fingerings.

Has anybody else noticed that?

Sure. I had my Boosey & Hawkes tuba shortened because it was low pitch. We cut the tube where it was most cylindrical (the only place to do it is on the back bow). We also shortened the tuningslide.  All in all 6,8 cm. The tuba is now playable in a=442 with enough tuningslide to put it in a=440. To make it perfect the tubing between valves should also be shortened  Image But since the soft parts (my lips) can bend the notes I can still play it in tune. A tuba is probably much easier to bend compared to a recorder.

If you have a f-valve on your trombone the slide positions are not equal to the straight horn. They are further apart on the f-valve. Since we have a slide system instead of fixed holes we can use the same system. We just streach the positions. On a fixed system with holes the adjustment is not possible so it becomes unplayable.

/Tom
ttf_robcat2075
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lengthening an instrument a tiny bit changes the scale

Post by ttf_robcat2075 » Thu Jan 18, 2018 3:04 pm

This is a classic problem with all woodwinds.

Aside from the problem of the holes no longer being in the same relationship to the length (were they really all that perfect to begin with?) there is a possible problem with the internal gap that is created by pulling out the head joint.

Clarinet player are big on things called tuning rings that are inserted in the gap between the barrel and the body so that the internal bore may be a truer cylinder.

Image


That said... I've never heard of recorder players using tuning rings. (I've never heard of recorder players tuning.)

But, by Google... they do exist.

I bet you could do a cheap experiment with some rubber washers found at the hardware store.


QuoteI was playing an alto recorder along with a youtube video (I play for the Christmas pageant every year, so I get it out and practice a bit).

The video pitch was a tiny bit lower.
Easier solution... strip out the audio and correct the pitch in Audacity.




ttf_Doug Elliott
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lengthening an instrument a tiny bit changes the scale

Post by ttf_Doug Elliott » Thu Jan 18, 2018 6:26 pm

Play a slide whistle instead of recorder?
ttf_Exzaclee
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lengthening an instrument a tiny bit changes the scale

Post by ttf_Exzaclee » Fri Jan 19, 2018 8:59 am

I've had a couple of my 2Bs cut down at the tuning slide, and this usually effects where the notes line up... most noticeable is the D above middle C, which when I cut about 1/2" off the tuning slide legs (1" total) went from being a flat note in the overtone series (1st position about 1/2" to 3/4" above the Bb) to being sharp (about 1/2" below the Bb.)

Has anyone else who cut their 2Bs notice this? Maybe it's just me?
ttf_Le.Tromboniste
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lengthening an instrument a tiny bit changes the scale

Post by ttf_Le.Tromboniste » Fri Jan 19, 2018 10:00 am

Quote from: timothy42b on Jan 18, 2018, 01:25PMI was playing an alto recorder along with a youtube video (I play for the Christmas pageant every year, so I get it out and practice a bit).

The video pitch was a tiny bit lower.  So I pulled the alto apart just slightly at the headjoint.  Maybe an eighth inch - certainly less than 1/4. 

This dramatically affected the pitch of most of the notes in the scale.  I actually could no longer play it.  It did not move them uniformly up or down, but spread them out so they sounded like wrong fingerings.

Has anybody else noticed that?

Yes. The problem is universal to all instruments, even strings. A violinist using the same instrument to play at A=415, A=430, A=440 and A=466 will have four slightly different versions of the fingerings, because everything except the open strings will line up differently. They will occasionally restring the instrument with thinner gauge strings (so they can achieve the same tuning with less tension), or move the bridge (same effect, except you can only do it so much without drastically changing the sound), which minimizes the problem but doesn't eliminate it completely. Fretted instrument players hate to change tuning pitch drastically, because it usually means having to change or at least adjust all the frets. When I play my ophicleide at A=430, I have to bend every note even more than usual because the keyholes are no longer in the optimal position. If I put an Eb crook in the bass sackbut in F,  I have 6 positions instead of 7. Of course with a trombone you have a slide to adjust, and other brass can bend while still playing with relative stability. Bending every single note on a recorder would be a real pain, especially given how you have to get used to a very steady airflow to avoid unvoluntary bending usually!
ttf_davdud101
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lengthening an instrument a tiny bit changes the scale

Post by ttf_davdud101 » Tue Jan 23, 2018 1:24 pm

Does this mean that drastic changes of the tuning slide on a trombone SHOULD also affect the distances between slide positions? We have good ears so we can usually adjust, but if the same slide positions (1-7) relative were measured to being in tune, and then the slide was pulled to tune the instrument way down and then the same distances were used between positions, would those positions be out of tune in comparison to the first tuning??
ttf_watermailonman
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lengthening an instrument a tiny bit changes the scale

Post by ttf_watermailonman » Tue Jan 23, 2018 2:19 pm

Quote from: davdud101 on Jan 23, 2018, 01:24PMDoes this mean that drastic changes of the tuning slide on a trombone SHOULD also affect the distances between slide positions? We have good ears so we can usually adjust, but if the same slide positions (1-7) relative were measured to being in tune, and then the slide was pulled to tune the instrument way down and then the same distances were used between positions, would those positions be out of tune in comparison to the first tuning??

Yes, distances are not the same when tuning A=440 and A=442 but you will probably not think of it. Just listen and adjust accordingly.

/Tom
ttf_robcat2075
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lengthening an instrument a tiny bit changes the scale

Post by ttf_robcat2075 » Tue Jan 23, 2018 3:21 pm

If we presume that 1st position is tuned to a proper Bb for each pitch then the difference in placement at 6th position is about 4mm

Sixth position would be 4mm shorter at A442 than at A440
ttf_timothy42b
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lengthening an instrument a tiny bit changes the scale

Post by ttf_timothy42b » Wed Jan 24, 2018 5:04 am

Quote from: davdud101 on Jan 23, 2018, 01:24PMDoes this mean that drastic changes of the tuning slide on a trombone SHOULD also affect the distances between slide positions?
Yes.

To move between notes - say move from a Bb to an A - requires one to lengthen the air column by a percentage. 

To move the next half step - say from A to Ab - is a move of the same percentage of the air column.  But the air column is now a couple inches longer.  So the same percentage is a different number of inches, by a very small amount. 

The distance between 6 and 7 is therefore larger than between 1 and 2.

With the tuning slide all the way in the trombone is somewhere around 9 feet long.  All the way out, maybe 9 feet 3 inches or so. 
ttf_robcat2075
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lengthening an instrument a tiny bit changes the scale

Post by ttf_robcat2075 » Wed Jan 24, 2018 7:24 am

Lessee... 9 ft trombone, 12ft in 6th position

If the tuning slide adds 3 in. then the total 6th position length will need to be 12 ft + 4 in to maintain proportions with the 9' 3" first position

However, three of those inches are already in the tuning slide so the new sixth position need to be 1/2 inch farther out on the slide.

In reality, the trombone is probably built so that the target 9 ft length happens near the middle of the tuning slide rather than all the way in so you'll never have a 9' 3" trombone. What you have is a range of about 8' 10.5" to 9' 1.5"


ttf_greenbean
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lengthening an instrument a tiny bit changes the scale

Post by ttf_greenbean » Wed Jan 24, 2018 8:23 am

Guys, there is a reason we play trombone with our ear and not a yardstick! 
ttf_timothy42b
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lengthening an instrument a tiny bit changes the scale

Post by ttf_timothy42b » Wed Jan 24, 2018 8:34 am

Quote from: greenbean on Jan 24, 2018, 08:23AMGuys, there is a reason we play trombone with our ear and not a yardstick! 

Yes, and it works for trombone.

It doesn't work well for recorder, which cannot alter the distance between finger holes when you lengthen or shorten the overall length of the instrument.

That's why I brought the topic up.  I was surprised at the magnitude of the effect, though I knew theoretically it should occur. 
ttf_BGuttman
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lengthening an instrument a tiny bit changes the scale

Post by ttf_BGuttman » Wed Jan 24, 2018 8:41 am

The "tuning rings" that Rob shows are quite thin.  If you watch saxophone players tuning their instruments by adjusting mouthpiece position you will note that they make VERY small adjustments.  Same goes for something like a recorder.  Pulling the mouthpiece out 1/8" is almost like making a C recorder in B.
ttf_timothy42b
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lengthening an instrument a tiny bit changes the scale

Post by ttf_timothy42b » Wed Jan 24, 2018 8:44 am

I play recorder in 2 octaves and work a little bit in the 3rd, because it tends to increase stability in the upper part of the 2cnd.

Pulling the head joint has slightly different effects in the upper octave.

Pulling the foot joint as well slightly reduces the effect, but makes the tone more harsh.

Experienced players have told me they do a lot with breath pressure to stay in tune.  I'm not at that level but I guess I need to pay more attention. 
ttf_robcat2075
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lengthening an instrument a tiny bit changes the scale

Post by ttf_robcat2075 » Wed Jan 24, 2018 8:52 am

That's a reason the flute superseded the recorder. A flute can tune most notes on-the-fly at any dynamic level but a recorder can't.
ttf_robcat2075
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lengthening an instrument a tiny bit changes the scale

Post by ttf_robcat2075 » Wed Jan 24, 2018 8:52 am

That's a reason the flute superseded the recorder. A flute can tune most notes on-the-fly at any dynamic level but a recorder can't.
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