Recently conducted subjective test results are presented here. The result compares two different modes of ISR against MP3 Surround and mpeg surround. ISR uses Teslapro as its core codec. An elaborate discussion on this was presented in NY 2007 AES convention. The same is available here.

Table shows the mean score of 12 expert listeners on 6 critical surround audio samples

In the second test ISR shows significant gains in terms of quality compared to recently standardized MPEG Surround. In these tests core codec for ISR and MPEG Surround was replaced with original audio as input. The below figure shows the subjective score:

Table shows the mean score of 12 expert listeners on 6 critical surround audio samples