These are the Fourth Doctor Adventures, season 1. Big Finish got the big man and they are doing a great job of keeping him! Rock on, BF.
1.01 - Destination Nerva 
1.02 - The Renaissance Man
1.03 - The Wrath of the Iceni
1.04 - Energy of the Daleks
1.05 - Trail of the White Worm
1.06 - The Oseiden Adventure