Как вывести звук через звуковую карту?

uses
 MMSystem;
type
 TVolumeLevel = 0..127;
procedure MakeSound(Frequency{Hz}, Duration{mSec}: Integer; Volume: TVolumeLevel);
 {writes tone to memory and plays it}
var
 WaveFormatEx: TWaveFormatEx;
 MS: TMemoryStream;
 i, TempInt, DataCount, RiffCount: integer;
 SoundValue: byte;
 w: double; // omega ( 2 * pi * frequency)
const
 Mono: Word = $0001;
 SampleRate: Integer = 11025; // 8000, 11025, 22050, or 44100
 RiffId: string = 'RIFF';
 WaveId: string = 'WAVE';
 FmtId: string = 'fmt ';
 DataId: string = 'data';
begin
 if Frequency > (0.6 * SampleRate) then
 begin
  ShowMessage(Format('Sample rate of %d is too Low to play a tone of %dHz',
  [SampleRate, Frequency]));
  Exit;
 end;
 with WaveFormatEx do
 begin
  wFormatTag := WAVE_FORMAT_PCM;
  nChannels := Mono;
  nSamplesPerSec := SampleRate;
  wBitsPerSample := $0008;
  nBlockAlign := (nChannels * wBitsPerSample) div 8;
  nAvgBytesPerSec := nSamplesPerSec * nBlockAlign;
  cbSize := 0;
 end;
 MS := TMemoryStream.Create;
 with MS do
 begin
  {Calculate length of sound data and of file data}
  DataCount := (Duration * SampleRate) div 1000; // sound data
  RiffCount := Length(WaveId) + Length(FmtId) + SizeOf(DWORD) +
  SizeOf(TWaveFormatEx) + Length(DataId) + SizeOf(DWORD) + DataCount; // file data
  {write out the wave header}
  Write(RiffId[1], 4); // 'RIFF'
  Write(RiffCount, SizeOf(DWORD)); // file data size
  Write(WaveId[1], Length(WaveId)); // 'WAVE'
  Write(FmtId[1], Length(FmtId)); // 'fmt '
  TempInt := SizeOf(TWaveFormatEx);
  Write(TempInt, SizeOf(DWORD)); // TWaveFormat data size
  Write(WaveFormatEx, SizeOf(TWaveFormatEx)); // WaveFormatEx record
  Write(DataId[1], Length(DataId)); // 'data'
  Write(DataCount, SizeOf(DWORD)); // sound data size
  {calculate and write out the tone signal} // now the data values
  w := 2 * Pi * Frequency; // omega
  for i := 0 to DataCount - 1 do
  begin
  SoundValue := 127 + trunc(Volume * sin(i * w / SampleRate)); // wt = w * i / SampleRate
  Write(SoundValue, SizeOf(Byte));
  end;
  {now play the sound}
  sndPlaySound(MS.Memory, SND_MEMORY or SND_SYNC);
  MS.Free;
 end;
end;
// How to call the function:
procedure TForm1.Button1Click(Sender: TObject);
begin
 MakeSound(1200, 1000, 60);
end;

Взято с сайта http://www.swissdelphicenter.ch/en/tipsindex.php

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