barmodel
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## barmodel

barmodel — Creates a tone similar to a struck metal bar.

## Description

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.

## Syntax

    ares barmodel kbcL, kbcR, iK, ib, kscan, iT30, ipos, ivel, iwid

## Initialization

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.

## Performance

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.

## Examples

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>

## Credits

Author: Stefan Bilbao
University of Edinburgh, UK
Author: John ffitch
University of Bath, Codemist Ltd.
Bath, UK

New in Csound version 5.01

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