E to Echo return.

E : Symbol for EMF. "E" value. The radial distance by which the edge of the reel flang~ extends beyond the outside layer of tape. .
e.m.f. (Elec.) The force which starts and maintains a current of electric­ity through a conductor; it is com­monly measured in terms of volt.
Ear. (Furn.) An upholstery term.re­ferring to the frame which forms the wings of a wing chair. Also a term used to refer to the projecting toprail ends of a fan back.

Eardrum. A thin sheet of tissue stretched across the end of the au­ditory passage which vibrates when sound waves hit it. .
Earmark. To place an identifying mark on a piece to indicate that it is to be set aside or used for some­particular purpose.
Earpiece. (Elec.) That part of a tel­ephone receiver which rests against the ear of the listener.
Earth. Thepartofacircuitorsystemof interconnections used as 'zero' ref­erence for signals; normally com­mon to chassis or screening elements in audio equipment. Sometimes connected to a genuine external. earth point or earth pin of mains socket.
Earthed. Connected to earth.
Earth indictor compaSs. (Aero.) A compass, the indications of which depend on the current generated in a coil revolving in the earth's magnetic field.
Earth loop. Arrangement of inter­connections between circuit units and/or input sources resulting in more than one path for the 'earth' side of signaVcarrying cables. See Hum-loop.
Earth station. A dish for reception of satellite communication.
Easel. (Furn.) Frame made to stand on the floor and support a picture.
Easement. (Arch.) The curved part of a handrail or baseboard. (Bldg.) In stair construction, an ease-off or triangular piece to match the inside string and the wall base where these join at the bottom of the stair.
Eaves. (Arch.) The projecting edges of a roof.
Eaves trough. (Arch.) A channel or trough at the eaves of a roof for carrying off rain water.
Ebonite. Black vuIcanite; or hard rubber.
Ebonize: (Cabwk. and Furn.) To stain or finish in imitation of ebony.
Ebony. A hard, heavy, durable, very dark tropical wood used in carv­ing the cabinetwork.

Ebullition. The bubbling of a liquid; boiling. .
Eccentric. (Engin.) A device used on engines for changing t~e rotary motion of the crankshaft mto a re­ciprocating motion of the slide valve.
Eccentric adjustment. (Auto.) The bringing of related parts into proper adjustment by turning an eccentri­cally bored bushing.
Eccentric clamp. (Metalwk.) A quick­acting clamping device which works on the principle of the ec­centric.
Eccentric fitting. (Plumb.) A fitting in which the center line is offset in the fitting.
Eccentric fluted reamer. (Mach.) A reamer so milled that the concave channels are unevenly spaced to obviate chattering, but placed ex­actly opposite to permit diameter measurement with a micrometer.
Eccentricity. The deviation Gf the center of two circles from one an­other.
Eccentric rod. (Engin.) The rod which connects the eccentric with the valve mechanism.
Eccentric strap. (Engin.) The metal ring or container which encircles the eccentric sheave and transmits its motion to the rods and valve gearing in a steam engine.
Eccentric turning. (Mech.) Lathe turning work which is not concen­tric with the axis. (Woodwkg. and Mach.) turned work not concentric with the axis of the main turned shaft. A mandrel is used with two sets of centers that offset tlie amount required for the eccentricity needed.

Echinus. (Arch.) An ornamental molding, sometime'S spoken of as egg-and-dart molding.
Echo-. The single repetition of a sound after that sound has taken place: hello-hello; an audio effect in which a tape loop, echo cham­ber, or other device causes a sound to be repeated a short period of time after it has been made; not to be confused with reverberation.
Echo bus. In a mixing console, the bus or channel which is used in feed a programme to the echo chamber, reverberation or echo device. Also known as the echo send bus.
Echo chamber room. Many of the older, larger studios still have echo chambers. This is (in its most sim­ple arrangement) a room contain­ing a microphone an speaker(s). The desired signals are fed to the chamber speaker (s) and the rever­berated, echoing sound picked up at the other end of the room by the microphone (s). A similar sys­ tem can be recreated at home in the bathroom. However, because of the sophisticated. DDL and dig­ital reverbs now on the market, new studios are opening without the need for an echo chamber.
Echolocation. A way of finding ob­jects by sending out ultra-sounds and listening for the echo from the object.
Echo return. A mixing console in­put that receives the signal from a reverberation chamber or device.Many mixing consoles have a.

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