From JWB:
This box set contains select material available to collectors that has not yet been given an official release. This set was compiled from the best sounding and lowest available gen sources (unlike the official box!). EQ was properly adjusted for every track. Mono material was reduced to true mono. Most, if not all, of the tracks have been speed corrected somewhere along the line. There was no hiss/noise reduction used on any material! Put away your "Outcesticides" and enjoy the ultimate Nirvana bootleg experience!