I've had mine since 1977.. bought when I was in Germany.. still sound precise and reveal every detail in any source you throw at them. They are not bass heavy, but they are extremely accurate when used to mix etc. Although most HD414SL are rated at 600 Ohms, I was able to choose between 600 or 50 Ohms as the store had two version. I have never seen the 50 Ohm model since. I recently had the impedance checked and they are measuring 47 Ohms.. Not bad after 41 years eh ! :)

I can't find anything negative to say other than if your a bass head look elsewhere.. they are not for you.

The find of the decade: NOS Sennheiser HD 414SL from up in the attic at a store in San Francisco. I already own a pair of 414s and Sony MDRV6 cans. The 414SL is so superior, I don't know where to start. The most liquid, smooth, detailed presentation yet. It makes CDs sound like analog. Comfortable.