I wonder if those editing sound on the computer are aware that some of the new energy saving light bulbs produce an electronic hum which can show up on the soundfiles - as I learned to my cost some time ago.
As an electrician with something like half a century's experience in the trade, I view the forcible introduction of energy-saving bulbs (here in Ireland at least), as little more than a money-spinning gimmick.
It is a fact that much of what is gained by the lower consumption of energy is lost in the manufacture of the new bulbs.
Were the people who introduced the law phasing out the manufacture of the old GLS bulbs,serious about energy saving, they would also have made it compulsary to fit the highly overpowered halogen exterior lights (all unnecessarily fitted with 500 watt tubes at the point of purchase) with sensors and sold with lower wattage bulbs.
It is still possible to drive around here at any hour of night and find houses permenantly lit up like Christmas trees from dusk till dawn.
Jim Carroll