Conclusion

I believe I'm right in the case of the Musketeer 3: leave the tubes in the 50's where they can't hurt anyone.  Introducing a device in the audio chain that intentionally adds distortion, however unobtrusive, is still nonsense.  Done right I believe tubes can sound very, very good.  But done-right will cost you much more than a Musketeer 3, and probably won't fit into your computer case.

The big problem here is that the Musketeer 3 is too sensitive to your source material.  If your MP3's are loud, chances are the Musketeer 3 will overload and create even more distortion.  The second problem is related to the first, in that it will reduce the volume.  This will make you turn it up, which will cause more distortion.  A revision to increase the volume without distortion would be great.

Another little problem is that it doesn't provide more than 2-channel stereo sound.  For a full 7.1 system, that's 4 Musketeer 3's.  It's a bit overboard, but even my transistorized heart is telling me, "wouldn't that be cool?"

Now beyond me being far too serious, the Musketeer 3 is indeed a cool bit of kit.  It just looks cool and oozes class, which overcome its shortfalls.  CoolerMaster didn't cut too many corners on it and it's engineered very well.  If you are shooting for an analog look for your rig, then this thing is for you.  The fact that the Musketeer 3 measurably changes the sound probably won't make a difference to people who want to have a unique look in their computers.  The Musketeer 3 will certainly provide that.  The Musketeer 3 is probably the best and most economical way to go if you want to play with tubes in your computer.

Recommended.