Recorded Sound Information (from Stereo Exchange employee, Greg Marston)

AIR PRESSURE CHANGES ARE SOUND Stereo Repair Technician 29 East 31st Street, 2nd Floor, between Madison and Park, NY NY 10016 212-725-8778 Glenn Marston said Electromagnetic impulses vibrate coil and magnet in the speaker. Optical Sound (off of film) through a 4 ohm rated speaker needs more resistence (more power from the amplifyer) than an 8 ohm speaker (Bose are usually 6 ohm). There is a sound acadamy curve. For de-emphasized bass, RIAA curve, a slant. For a magnetic representation of sound a bias signal is applied. Germany (Nazi era) produced Magnetic Tape Ampex is Bing Crosby's tape company Magnetic charges also stored on Mylar and Acetate 2 coils exciting the gap. A bias signal is applied, shaking up the magnetic particles, making it linear. The speaker transforms the electric current back into sound. Not only does each live performance of a song add another compositional layer to an already composed piece... Each play back of a recording is its own a unique performance of the recording, sent to our ears by the equipment that generates it. The sound travels as an electric current through wire and the speaker (which modulates air pressure) transfers it back into sound.