Two sites that I find immensely rewarding are:
1) Spanish television RTVE ŕ la carte:
http://www.rtve.es/alacarta/videos/los-conciertos-de-la-2/Currently five hundred and seventeen videos are available. Scroll down to the blue lines headed "Los últimos 517 programas de Los conciertos de La 2," and to start the videos, click on the links in the left-most column, entitled "Titulo." Many rare items are discoverable, dating from ancient madrigals to the most avant-garde.
This Spanish site was originally drawn to my attention by a contributor to UC, to whom I am very grateful indeed.
and
2) ARTE Concert (recently revamped and arranged more logically):
http://concert.arte.tv/fr/videos/musique-classiqueCurrently seventy-nine videos are available. Click on "VOIR LES CONCERTS SUIVANTS" to display subsequent pages. To start the video, click on the picture you desire.
Many thanks to Mr. McGowan for first drawing my attention to the ARTE.
From both of these sites it is a simple matter to download the items using
Firefox version 27 with the extension
Flash Video Downloader version 5.3.2. Start playing the video, then pause it, and click the blue arrow of Flash Video Downloader to select the file you want. When something is being downloaded, progress can be monitored in Firefox's usual download panel.