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
;

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