Оформил: DeeCo
Автор: http://www.swissdelphicenter.ch

procedure GetMIDIOutDevices(Devices: TStrings);
 var
   i, DNum: Integer;
   Caps: TMIDIOUTCAPSA;
 begin
   DNum := MIDIOutGetNumDevs;  // Number of Devices 
  for i := 0 to DNum - 1 do     // Query Devicenames 
  begin
     MIDIOutGetDevCaps(i, @Caps, SizeOf(TMIDIOutCapsA));
     Devices.Add(string(Caps.szPname));
   end;
 end;

 // Usage: 

var
   MIDIDevices: TStringList;

 begin
   MIDIDevices := TStringList.Create;
   try
     GetMIDIOutDevices(MIDIDevices);
     // Do anything with the device name list 
  finally
     MIDIDevices.Free;
   end;
 end;