If sound data resulting from a recording session has been stored in memory, this method will return the size in bytes of the buffer. Note that, during the recording session, you can obtain the growing buffer's size in real time through the RecordingSize event.
The buffer's address in memory can be retrieved through the RecordedSound.GetMemoryPtr method.
For further details about recorded sound methods refer to the RecordedSound class section.
For further details see the How to perform a recording session section.