Wow are you sure there isn't something wrong with your Zeppelin catalog? I consider Zeppelin's collection to be quite possibly the best sounding records of the 70s, due in part to the masterful production of a Mr. Jimmy Page. Clean and succinct, with studio precision, but always retaining a volatile, live feel and a raw rock n roll flavor.
But hey maybe you'll disagree with my choice and we can be even, lol. :-D
My pick is NEVERMIND. Great songs. Absolutely awful, awful tinny, stale, unlistenable production. And I don't even understand why the production sucks so much because that same guy did good with L7 in that same year. Maybe the new remaster will be good.