Negative Feedback

The practice of returning some of an amplifier's, or amplifier stage's, output to its input 180 degrees out of phase. This has a tendency to reduce distortion and make an amplifier more stable. Too much reliance on negative feedback results in very high IM (intermodulation distortion) readings, and poor sonic performance.

Negative Feedback Loop

A comparative circuit used in both audio applications (Sigma Drive, Sigma Servo) and voltage applications to ensure that a given circuit is performing appropriately.

Negative LCD

A liquid crystal display employing a dark backfield with lit elements. This results in a primarily dark display, which improves cosmetic integration with a dark colored headunit.

Negative Lead

The lead or line connected to the negative terminal of a current, voltage, or power source.

Neodymium

A rare earth magnet that is 10 times stronger than standard ferrite magnets.

Neoglass™ Tweeters

This tweeter material is made of woven fiberglass making it extremely durable and able to withstand abuse and higher power. The sonic properties of this material are also excellent delivering smooth high frequency extension clear out to 22kHz.

No

The reference efficiency of a driver with a half-space acoustical load.

Noise

Perceived sounds not in the original soundtrack. Such things as hiss, crackle, pops, hum, and buzz, are typical of the types of extraneous signals described as noise. Inherent noise in the electronic processing in any sytem is measured in decibels relative to the amplitude of the original signal.
Sounds perceived as noise are heard in contrast to the sound that is the object of attention. Thus, a noise signal measured at 15 deciBels below the output of Tchaikovski's 1812 Overture finale would probably not even be heard; while a slight hiss at 55 dB below the level of a soft piano passage would be annoyingly obvious.

Generally, any piece of equipment which generates ambient noise of more than 90 dB below the level of a typical audio signal is noise free as far as most human perception is concerned

Nominal Impedance

The minimum impedance a loudspeaker presents to an amplifier, directly related to the power the speaker can extract from the amplifier. This is used by a manufacturer to represent the load the speaker will provide to an amplifier.

Non-Delay Play

A disc changer feature with significantly reduced silence between the time one disc is finished, and the next disc is loaded and cued.

Normally Closed

Refers to the electrical state in which a switch may rest. Its contacts are held together or closed so that current is allowed to flow through its contacts.

Normally Open

Refers to the electrical state in which a switch may rest. Its contacts are held apart or open so that no current flows through its contacts.

NTSC

National Television System Committee - Refers to the standards used for video broadcast and playback signal parameters.