Recording studios could get a good sound back then, just witness the prog rock offerings and the ability to quite accurately get an orchestra balanced. I was playing with 48 track in the late '70s and the equipment was far from new. AKG mic references take me back too!

That said, folk acts weren't in the megabuck category and the quality of recordings reflected the budgets somewhat. True, a good sound engineer and producer could compensate somewhat but missing highs and lows are a feature of the equipment being used and the treatment of the master cut.

I suppose it is part of the folk tradition that Nic Jones didn't have access to the same gear as Rick Waleman. Live with it.

If you can't live with it, the Cheapest audio cleaning software, even shareware could rack it up a notch or two.