| Term | Definition |
|---|---|
| Satellite | A satellite speaker is usually fairly small, and does not reproduce the lowest frequencies. Usually meant to be used with a woofer or subwoofer. |
| Sd | The effective piston area of a driver. |
| Sealed Enclosure | An air tight enclosure that completely isolates the back wave of the driver from the front. Very tight, defined sound (with Qtc = 0.707) with very good transient response and power handling. |
| Sensitivity | A measurement of how much power is required for a loudspeaker to achieve a certain output level. The general standard used is on-axis SPL (Sound Pressure Level) at 1-watt input, 1-meter distance. |
| Signal-to-Noise Ratio (SN) | The range or distance between the noise floor (the noise level of the equipment itself) and the music signal. |
| Sine Wave | The waveform of a pure alternating current or voltage. It deviates about a zero point to a positive value and a negative value. Audio signals are sine waves or combinations of sine waves. The waveform of a pure alternating current or voltage. It deviates about a zero point to a... Read More |
| Single-Ended | Type of amplification often, (but not always), using vacuum tubes. Typically low power output, low damping factor and relatively high distortion. Single-ended enthusiasts claim that the sound quality is more "real". We highly endorse this type of amplifier if done properly. |
| Sound Pressure Level (Spl) | Given in decibels (DB) is an expression of loudness or volume. A 10db increase in SPL represents a doubling in volume. Live orchestral music reaches brief peaks in the 105db range and live rock easily goes over 120db. |
| Sound Waves | Sound waves can be thought of like the waves in water. Frequency determines the length of the waves; amplitude or volume determines the height of the waves. At 20Hz, the wavelength is 56 feet long! These long waves give bass its penetrating ability (why you can hear car boomers... Read More |
| Soundstage | A listening term the refers to the placement of a stereo image in a fashion that replicates the original performance. A realistic soundstage has proportional width, depth and height. |
| Speaker Level | Taken from the speaker terminals. This signal has already been amplified. |
| Spider | The flexible material that supports the former, voice coil, and inside portion of the cone within the speaker frame. |
| Standing Wave | A buildup of sound level at a particular frequency that is dependent upon the dimensions of a resonant room, car interior, or enclosure. It occurs when the rate of energy loss equals the rate of energy input into the system. This is what you hear when you listen into... Read More |
| Stereo | From the Greek meaning solid. The purpose of stereo is not to give you separate right and left channels, but to provide the illusion of a three-dimensional, holographic image between the speakers. |
| Subwoofer | A speaker designed exclusively for low-frequency reproduction. A true subwoofer should be able to at least reach into the bottom octave (20-40Hz). There are many "subwoofers" on the market that would be more accurately termed "woofers". |
| Super-aural | Perhaps, one of the largest category of headphones, although they were more commonly sold with personal stereos in the 1980s. Super-aural headphones have pads that sit on top of the ears, but do not completely enclose them. Models such as the Grado SR60, Koss Porta Pro, and... Read More |
| Surround (Suspension) | The outer suspension of a speaker cone; holds the diaphragm in place but allows it to move when activated. Usually made of foam or rubber. |
| Surround Sound | Sound extracted from the stereo signal sent to smaller rear or side speakers used in a home theater. |
