Cheh knows the material well. However, it sounds like she is recording these lectures on top a mountain or inside a wind tunnel. She also needs to take a few steps back from the mic, there is too much distortion, its a headache to listen to. The CDs do not contain titles to the lectures, when burned onto my computer they were labeled as (Track 01, 02, 03, etc). This was especially annoying because I had to manually create albums within itunes and create titles to each individual track, otherwise my iphone would play the track 01 (disc 01) then play track 01 (disc 02) and so on and so forth.