I've been listening to the podcast for quite a long time now, and the sound quality is great - even when interviewing many participants from different countries.
How is this done, technically? Obviously, the sound quality is higher than the average Skype call.
Does each participant record its own voice simultaneously, and the different channels are synced later? this seems to be quite difficult.
Update: I would appreciate a practical solution I could suggest to some Podcast I know, which records calls via phone on a mediocre quality.