Unlike most other headphone surround sound emulators, Waves NX does a relatively good job at preserving the quality of the original sound while simulating an out-of-your-head soundstage. But let’s see how it actually changes the sound.
I loaded a 192KHz Dirac delta impulse into Adobe Audition and applied Waves NX to it with these settings:
Sending an impulse on the left channel yields this:
Why is there no interaural time difference?
This lack of ITD effectively makes the soundstage more frontal at the cost of width. But that’s not the proper way to do binaural audio, is it?
Here is the frequency response of the left and right channels:
I processed “Hurt” by Johnny Cash (red) and “Hotel California” by the Eagles (green) through Waves NX. Here is the frequency response difference compared to the original track.
There is apparently some comb filtering going on. The frequency responses of the songs and the impulse are all altered very differently. This could indicate that the processing that happens in Waves NX is more complex and dynamic than a simple convolution.