Chapter 3: Glossary of Terms | 31 |
the amplifi er that allows a single input to feed two combined output channels in order to provide a single output with twice the current of an individual channel in Stereo or Dual mode.
Peak
On a graph of a sound wave or signal, the highest point in the waveform. The point of greatest voltage or sound pressure in a cycle.
Phase Response
The measure of displacement of a
Phone Plug
A cylindrical plug, usually
Phono Plug
A coaxial plug with a central pin for the hot signal and a ring of
PIP™
PIP stands for Programmable Input Processor. These are optional modules that can be plugged into any
PIP2™
The PIP2 standard, announced in 1998, upgraded the PIP feature set and requires both 18- and
Polarity
In electronics, the relationship between two points that have opposite electric potentials (one is positive, the other nega- tive) irrespective of time. This is not the same as being 180 degrees out of phase (although the results can be similar).
Phase implies a relationship with time, polarity does not.
Potentiometer (Pot)
An electronic component that is used to provide variable control over an electronic circuit. It is usually controlled by a rotary knob which can be turned by hand; a volume control is a good example of this.
Power
Literally, the rate at which energy is consumed. Power is expressed in Watts, abbreviated W. In electrical circuits, power is determined by the amount of resistance (R) times the amount of current squared with the following expression: P=I2R.
Power Amplifier
In audio, an electronic device that amplifi es or increases the
power level fed into it to a level suffi cient to drive a loud- speaker.
Radio Frequency Interference (RFI)
Removable Terminal Block (Buchanan®, Phoenix)
A series of screw terminal connections arranged in a line on a removable connector. Often found in
Resistance
The opposition of a circuit to a fl ow of direct current. Resis- tance is measured in ohms. The symbol Ω (omega) is often used to represent resistance. Ohms law defi nes resistance as voltage (V) divided by current (I) with the following expression: R=V/I.
Resistor
An electronic component that opposes current fl ow.
Sensitivity
In audio terms, sensitivity is the minimum amount of input signal required to drive a device to its rated output level. Normally, this specifi cation is associated with amplifi ers and microphones, but FM tuners, phono cartridges, and most other types of gear have a sensitivity rating as well.
Shield
In electronic terms, a shield is a conductive enclosure, protecting its contents from magnetic and electrostatic fi elds. Since audio conductors and circuits tend to be extremely sensitive to such fi elds, shields are very important. In cabling, shields often consist of braided copper strands wrapped around the signal conductors. The amount of coverage the shield provides is directly related to the noise and hum per- formance of the cable. Some cables offer a shield consisting of a thin wrap of metallic sheeting, which can offer complete coverage of the encased signal conductors.
The ratio in decibels between signal voltage and noise volt- age. An audio component with a high S/N has little back- ground noise accompanying the signal; a component with a low S/N is noisy.
Sine Wave
A wave following the equation y = sin x, where x is degrees and y is voltage or sound pressure level. The waveform of a single frequency. The waveform of a pure tone without harmonics.
An unbalanced line (see Unbalanced).
Slew Rate
Slew rate is the ability of a piece of audio equipment to reproduce fast changes in amplitude. Measured in volts per microsecond, this spec is most commonly associated with amplifi ers, but in fact applies to most types of gear. Since high frequencies change in amplitude the fastest, this is where slew rate is most critical. An amp with a higher slew rate will sound “tighter” and more dynamic to our ears. Slew rates in amplifi ers are often limited to useful levels to provide protec- tion to the amplifi er from
English
Amplifier Application Guide
