barmodel — Creates a tone similar to a struck metal bar.
Audio output is a tone similar to a struck metal bar, using a physical model developed from solving the partial differential equation. There are controls over the boundary conditions as well as the bar characteristics.
iK -- dimensionless stiffness parameter. If this parameter is negative then the initialisation is skipped and the previous state of the bar is continued.
ib -- high-frequency loss parameter (keep this small).
iT30 -- 30 db decay time in seconds.
ipos -- position along the bar that the strike occurs.
ivel -- normalized strike velocity.
iwid -- spatial width of strike.
A note is played on a metalic bar, with the arguments as below.
kbcL -- Boundary condition at left end of bar (1 is clamped, 2 pivoting and 3 free).
kbcR -- Boundary condition at right end of bar (1 is clamped, 2 pivoting and 3 free).
kscan -- Speed of scanning the output location.
Note that changing the boundary conditions during playing may lead to glitches and is made available as an experiment. The use of a non-zero kscan can give apparent re-introduction of sound due to modulation.
Here is an example of the barmodel opcode. It uses the file barmodel.csd.
Example 78. Example of the barmodel opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in No messages -odac -iadc -d ;;;RT audio I/O ; For Non-realtime ouput leave only the line below: ; -o barmodel.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; Initialize the global variables. sr = 44100 kr = 4410 ksmps = 10 nchnls = 1 ; Instrument #1. instr 1 aq barmodel 1, 1, p4, 0.001, 0.23, 5, p5, p6, p7 out aq endin </CsInstruments> <CsScore> i1 0.0 0.5 3 0.2 500 0.05 i1 0.5 0.5 -3 0.3 1000 0.05 i1 1.0 0.5 -3 0.4 1000 0.1 i1 1.5 4.0 -3 0.5 800 0.05 e /* barmodel */ </CsScore> </CsoundSynthesizer>