This is music archaeology of the first half of the 20th century, preserved by Hermann May and presented to us by Koch Schwann. Don’t ask me about the sound. It is the artistic value that matters here.
The series has 24 volumes of double CDs. Furtwängler’s can be found in six volumes: Vols 2, 4, 6, 10, 11 and 20.
Wilhelm Furtwängler Journal 