The Tonehole as a Two-Port Loaded Junction
It seems reasonable to expect that the tonehole should be
representable as a load along a waveguide bore model, thus
creating a loaded two-port junction with two identical bore ports on
either side of the tonehole. From the relations for the loaded
parallel junction (C.101), in the two-port case
with
, and considering pressure waves rather than force
waves, we have
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(10.63) |
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(10.64) |
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(10.65) |
Thus, the loaded two-port junction can be implemented in ``one-filter form'' as shown in Fig. 9.48 with





Each series impedance in the split-T model of
Fig. 9.43 can be modeled as a series waveguide
junction with a load of
. To see this, set the transmission
matrix parameters in (9.55) to the values
,
, and
from (9.51) to get
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|
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(10.66) |
where






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|
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(10.67) |
Next we convert pressure to velocity using


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|
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(10.68) |
Finally, we toggle the reference direction of port 2 (the ``current'' arrow for


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|
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(10.69) |
where

Next Section:
Bowing as Periodic Plucking
Previous Section:
Tonehole Filter Design