I was pleased to read the "Why do you need a headphone amp?" boxout in the current issue's Headphone Amplifier Test Express, as I've often wondered the same thing. But, please tell me: Assuming you already have a source connected to a stereo amplifier, and want to continue listening through speakers as well as headphones, then how do you link in a headphone amp to such a system? Oh, and in respect to the Lehmann Rhinelander review: What an earth is a "front-mounted metal selector"? Do you hit this when you listen to Metallica?!!?