For about three years, now, I've routinely used these size large
disposable, elasticized, ear pad covers on all of my fullsize headphones:
http://www.amazon.com/Large-Stretchable-Headphone-Covers-Earmuff-style/dp/B009CDXPCG
They're great for protecting velour and leather.
I've found them to be sonically transparent, but surely they have some impact - I'm just saying that if it were measured, it's got to be a fraction of a dB of attenuation. Best of all, they make the ear pads more comfortable in warm weather - especially leather pads, as with the LCD-2.
They're large enough to fit my HD800, but not large enough for the AKG K550 for example.
You can just make out the covers in this photo of the HD800, on the side table at my recliner:
iPad 3 streaming TIDAL 44/16 > Pure i-20 Coaxial Out > Metrum Octave MkII > NuForce HA-200 > HD800
The Pure i-20 is rubber-banded to the marble slab of cheese slicer for ballast.
A smaller size of disposable cover works well with the DT1350 or Amperior, for example:
http://www.amazon.com/Small-Stretchable-Headphone-Covers-standard-size/dp/B009CF1NM8
Everyone who has ever bought used headphones from me can attest that the pads were in like-new condition. The foam inside some pads might break down over a sufficient time frame, but at least I'm not accelerating their demise by having to wash the pads.
Mike