clarinet barrel lengths
genericaudioperson
I believe the standard clarinet barrel length is 66mm. Does anyone
know how many cents sharper a 65mm or 64mm barrel is?
Bob Lombard
If there is a 'standard' barrel length I haven't figured out what it is.
I'm interested in the cents question though. My tuner is graduated in
Hz, and I don't know how to translate that into cents.
Bob
genericaudioperson
100 cents is a full 1/2 step (semitone). The frequency doubles every
octave. But in between, it is logarithmic in a 12-tone equal
temperament situation, so the calculations become tedious. Is your
tuner digital and fairly new? Usually there is an option to set it
between hertz and cents. Unless your tuner only tells you A-440 and
not much else. The modern tuners I use will tell you the note you
are playing, and how far off you are in terms of cents. I';m talking
about 12-tone equal temperment, referenced from A-440. You can set
A-442 and things like that if you want. A good cheap tuner is the
Korg CA-30, which is $20. You can spend hundreds for a strobe tuner,
but the CA-30 is fine. As soon as the room temperature heats up in
the auditorium, whatever small gain you got from the strobe will be
far lost. Strobes are great for fine tuning an instrument that has a
degree of tuning permanence to it.
Stephen Howard
It varies for each player - shortening the length of a clarinet will
raise the pitch, but there are other factors that have a bearing on
tuning.
Typically you'd see anything from a rise of 2 to 5 Hz by shaving 2mm
off a barrel.
A novel way of getting around the problem is an adjustable barrel:
http://www.bill-lewington.com/click.htm
Regards,
--
Stephen Howard
Woodwind repairs & period restorations
http://www.shwoodwind.co.uk
Bennett Price
http://www.sengpielaudio.com/calculator-centsratio.htm
chalumeauman
Ok, what's your best recommendation for a headache? ')
carlb
I don't know the cents but it's not constant. For example, when I
start playing I start with my shortest barrels (for both A and Bb)
which are 63 mm. However, as I warm up, I then switch to longer
barrels to stay in tune (65 or 66 for Bb and 64 for A). The other
factor that's come in to play for me is the mouthpiece. When I
switched to a Pomarico crystal mouthpiece, I found that I was
generally flatter, which is why I got barrels as short as 63 mm. I
check my tuning with an electronic tuner while playing and change to
longer barrels as I get sharper.
Carl
Wist
0bfe8c...@i20g2000prf.googlegroups.com:
Calculations are not so difficult :
* First let's calculate the frequency ratio for 1 cent :
10exp((LOG(2)/1200)) = 1.00057779
expressing that 1 cent is the 1200th part of an octave.
* Assume average length of a clarinet os around 665mm
(see http://fr.wikipedia.org/wiki/Clarinette )
* Shaving 2mm from that increases the frequency by a ratio of :
665/663=1.003016561 (frequency is proportional to length)
* Converting this ratio into cents gives :
(Log(1.003016561)/Log(1.00057779)) = 5.21 cents
Christophe
John Aldridge
wi...@nospam.fr says...
> carlb <c.b....@att.net> wrote in news:689a3b90-538a-405a-9c89-
> 0bfe8c...@i20g2000prf.googlegroups.com:
>
> > On Nov 23, 12:52 am, genericaudioperson
> > <genericaudioper...@hotmail.com> wrote:
> >> Hello,
> >>
> >> I believe the standard clarinet barrel length is 66mm. Does anyone
> >> know how many cents sharper a 65mm or 64mm barrel is?
>
>
> * First let's calculate the frequency ratio for 1 cent :
> 10exp((LOG(2)/1200)) = 1.00057779
> expressing that 1 cent is the 1200th part of an octave.
>
> * Assume average length of a clarinet os around 665mm
> (see http://fr.wikipedia.org/wiki/Clarinette )
>
> * Shaving 2mm from that increases the frequency by a ratio of :
> 665/663=1.003016561 (frequency is proportional to length)
>
> * Converting this ratio into cents gives :
> (Log(1.003016561)/Log(1.00057779)) = 5.21 cents
It depends what note you are playing, though: a quick experiment with
the tuner indicates that when I pull my barrel out by 1/8 inch (3.2 mm),
the B just above the break gets about 16 cents lower, but the Bb just
below it more like 50 cents. That seems consistent with the fact that
the resonating length is about 3 times shorter for the Bb.
I also think Christophe's length is little too long, even for the B. At
a sound speed of 330 m/s, that B (= concert A, 440 Hz) has a wavelength
of 0.75 metres. Above the break the clarinet resonates at 3/4
wavelength, which makes an effective resonating length of 563 mm.
However, even with this figures for the length that makes 1/8 inch
increase in length about 10 cents rather than my measured 16. I don't
know why this is -- maybe I'm lipping the note differently, though I'm
trying not to.
--
Cheers,
John
John Aldridge
no....@jjdash.demon.co.uk says...
> I also think Christophe's length is little too long, even for the B. At
> a sound speed of 330 m/s, that B (= concert A, 440 Hz) has a wavelength
> of 0.75 metres. Above the break the clarinet resonates at 3/4
> wavelength, which makes an effective resonating length of 563 mm.
Minor correction, allowing for warm air:
At (say) 30C, speed = 349 m/s, which gives a resonating length of 595 mm
and a cents change (for 1/8 inch increase in length) of 9.2.
--
Cheers,
John
Doctroid
John Aldridge <no....@jjdash.demon.co.uk> wrote:
But the important thing is it's not an across-the-board cents change of
9.2; the effect is (much) larger for notes below the break since the
effective length of the instrument for those notes is much smaller. In
other words a 1-2 mm longer (shorter) barrel can effectively address
sharpness (flatness) in the throat notes while leaving the long notes
relatively unchanged; it isn't appropriate for correcting long notes
problems.
Bob Lombard
>
> But the important thing is it's not an across-the-board cents change of
> 9.2; the effect is (much) larger for notes below the break since the
> effective length of the instrument for those notes is much smaller. In
> other words a 1-2 mm longer (shorter) barrel can effectively address
> sharpness (flatness) in the throat notes while leaving the long notes
> relatively unchanged; it isn't appropriate for correcting long notes
> problems.
There are spacers available, intended to be placed between the joints.
Does the effect you describe mean that such spacers can't do what they
are claimed to do, i.e. flatten notes in the lower joint?
Bob
Lance in AZ
I guess I'd raher have a bunch of engineers playing the clarinet than
a bunch of musicians building a bridge.
Do you guys EVER play any music?
John Aldridge
561517...@n33g2000pri.googlegroups.com>, lan...@gmail.com says...
> I guess I'd raher have a bunch of engineers playing the clarinet than
> a bunch of musicians building a bridge.
>
> Do you guys EVER play any music?
Yes. Doesn't stop me being interested in the engineering aspects too.
--
Cheers,
John
Wist
news:MPG.23ae0c1f...@news.demon.co.uk:
Same goes for me, I play the clarinet in a Symphony Orchestra, and
nevertheless I take interest in understanding the basics of how my
instrument works... Some drivers never open the lid of their car,
some others do. Lance only shows that being narrow minded is also
an option.
Bob Lombard
Well, shucks. I thought the guy was attempting humor. It worked that way
for me, but then I laugh easily.
Bob
Stephen Howard
Worked for me too.
Regards,
--
Stephen Howard
Woodwind repairs & period restorations
sdm_sax
wrote:
> In article <MPG.23a7abc18114e6dc989...@news.demon.co.uk>,
> no.s...@jjdash.demon.co.uk says...
You need to allow for end correction. Also sound travels at 330m/s at
sea level. Altitude plays its part and can impact on pitch. (Another
reason why tuning barrels aren't fixed!)
According to Backus if a clarinet is 67cm long then if you attach a
pipe to the mouthpiece to produce the same lower note you need a pipe
only 60cms long.