This was a weird time for Art Pepper, it was 1964 and he had just come out from a long stretch in San Quentin prison for drugs related offences. He had gone in just after making some great recordings. He was worried about his "old" style, so he was listening heavily to Coltrane while inside. He also changed his tone, IMHO overblowing here, and losing his "pretty" sound.
This is an extract from the Ralph Gleason show, I have the full show on DVD. There is also an interview which kinds of skirts aroud Art's recent past, typical of the time.
Some of the tunes he writes around this time, like "The Trip" are recorded later (1976) with his old tone back, and are very good. On the DVD he finishes off with a great hard driving blues.
An interesting clip, he is playing with Frank Strazzeri on piano, Hersh Hamel on Bass and Bill Goodwin on Drums
Thanks for posting this link, very interesting, but not typical Pepper by any means!
Look out for "Notes from a Jazz Survivor" made shortly before he died, available on DVD, this shows him playing with great tone and power, at his best I would say.