37 performing what’s the feet – Roland FP-7 User Manual
Page 37
37
Performing
What’s the feet?
“Feet” is a term that began as a measurement of the length of the pipes in a pipe organ.
The pipes that produce the basic pitch (fundamental) for each note are considered to be
“8 feet” in length.
Therefore, a pipe producing a pitch one octave below that of the reference of 8' (eight
feet) would be 16'; for one octave above the reference, the pipe would be 4', and to take
the pitch up yet another octave it would be shortened to 2'.
The pitches of the harmonic bars are related as follows.
On tonewheel organs, the high-pitched footage for a portion of the high range, and the
low-pitched footage for a portion of the low range are “folded-back” in units of one
octave.
Folding back the high-frequency portion prevents the high-frequency sounds from being
unpleasantly shrill, and folding back the low-frequency portion prevents the sound from
becoming “muddy.”
On the FP-7 faithfully simulates this characteristic.
16'
8'
4'
2'
1'
5
1
/
3
'
2
2
/
3
'
1
3
/
5
'
1
1
/
3
'
one octave
below
5th
root
8th
12th
15th
17th
19th
22nd
8' =
When the middle C (C4) note is pressed, each
harmonic bar will sound the following notes.
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