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copied!<p>I can't believe it... I went back to System.Media.SoundPlayer and got it to do just what I want... no giant dependency library with 95% unused code and/or quirks waiting to be discovered :-). <strike>Furthermore, it runs on MacOSX under Mono (2.6)!!!</strike> <em>[wrong - no sound, will ask separate question]</em></p> <p>I used a MemoryStream and BinaryWriter to crib a WAV file, complete with the RIFF header and chunking. No "fact" chunk needed, this is 16-bit samples at 44100Hz. So now I have a MemoryStream with 1000ms of samples in it, and wrapped by a BinaryReader. </p> <p>In a RIFF file there are two 4-byte/32-bit lengths, the "overall" length which is 4 bytes into the stream (right after "RIFF" in ASCII), and a "data" length just before the sample data bytes. My strategy was to seek in the stream and use the BinaryWriter to alter the two lengths to fool the SoundPlayer into thinking the audio stream is just the length/duration I want, then Play() it. Next time, the duration is different, so once again overwrite the lengths in the MemoryStream with the BinaryWriter, Flush() it and once again call Play().</p> <p>When I tried this, I couldn't get the SoundPlayer to see the changes to the stream, even if I set its Stream property. I was forced to create a new SoundPlayer... every 40 milliseconds??? No.</p> <p>Well I want back to that code today and started looking at the SoundPlayer members. I saw "SoundLocation" and read it. There it said that a side effect of setting SoundLocation would be to null the Stream property, and vice versa for Stream. So I added a line of code to set the SOundLocation property to something bogus, "x", then set the Stream property to my (just modified) MemoryStream. Damn if it didn't pick that up and play a tone precisely as long as I asked for. There don't seem to be any crazy side effects like dead time afterward or increasing memory, or ??? It does take 1-2 milliseconds to do that tweaking of the WAV stream and then load/start the player, but it's very small and the price is right!</p> <p>I also implemented a Frequency property which re-generates the samples and uses the Seek/BinaryWriter trick to overlay the old data in the RIFF/WAV MemoryStream with the same number of samples but for a different frequency, and again did the same thing for an Amplitude property.</p> <p><a href="http://sourceforge.net/projects/morse-rss-news" rel="nofollow noreferrer">This project is on SourceForge</a>. You can get to the C# code for this hack in SPTones.CS from <a href="http://morse-rss-news.svn.sourceforge.net/viewvc/morse-rss-news/trunk/locrss/" rel="nofollow noreferrer">this page in the SVN browser</a>. Thanks to everyone who provided info on this, including @arke whose thinking was close to mine. I do appreciate it. </p>

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