Tyler,
Here's a public-available link to the User Guide. This may be of use to you.
http://www.waves.com/1lib/pdf/plugins/nx.pdfThe section in the guide relating to "Head Tracker", Chapter 4, is for a hardware device that can be used to help enhance the plugin's interpretation of a specific speaker(s) setup. Since I didn't purchase this to accompany the plugin, I cannot comment on it.
My impressions of the plugin so far...
It is excellent.
I've always found it a little frustrating how the the sound through my speakers and through my headphones disagreed with one another. It's not a major disagreement but it's enough to make mixing a little more challenging. If I mix to my headphones, the sound is slightly unbalanced in my speakers (and vice-versa).
When I tested the plugin, this is the process I followed...
1. I put the Nx Virtual Mix Room as the last plugin in the Master control (in Reaper) and then added settings for speaker angle and my head-size (circumference, ear-to-ear around the back of the head).
2. I then opened a song that I was happy with the way it was mixed.
3. When the song was playing and with headphones on, I toggled between active/non-active for the plugin. There was definitely a difference in sound.
4. With the plugin active, when I removed my headphones and listened to the speakers. The sound that I had been hearing in my headphones was very closely paralleled by what I was now hearing from the speakers. Was it identical? I don't know but it sounded the same. With the plugin non-active, the sound between headphones and speakers was, again, noticeably different.
Lastly, I have to say that Waves installation software called "Waves Central" made installing and activating the two plugins I bought very easy.
All in all, it's thumbs up from me!
Hopes this information helps,
Noel