Lineage: 1st gen cassettes (TDK SA 90) x3 > Nakamichi 670 pitch & azimuth-adjusted playback deck > Nakamichi Outboard Dolby B Unit > Wavelab 96/24 > Izotope 44.1/16 > flac. Info file says, "Alternate set of unmarked tapes for this show transferred with Dolby B on as per Mike's notes on the tape labels using an adjustable outboard Dolby B unit. This is the 1st time (May 2010) these tapes have ever been digitized. The sound is completely unaltered except for pitch correction during playback and fades added for each of the tape flips."