Circuits & Schematics Audio

A question that arises frequently in audio and signal processing applications is this: How can I control gain on dual channel (e.g., stereo) inputs simultaneously with only a single knob? Of course, an obvious solution would be to simply use a dual ...

Low-frequency filters, particularly at audio frequencies, usually take the form of active filters. These filters eliminate expensive inductors with windings of many turns. Both analog and digital active filters are most compatible with large-scale ...

The sample and hold circuit (Figure 3) is considerably more complex than the oscillator. This is unfortunate but unavoidable. It's the S/H that gives this design its speed (fast settling time) and very low distortion, and it's very unlikely ...

Introduction As discussed in the article [ 1 ], although a sinewave is the simplest possible waveform, it is also one of the hardest to generate in pure form. Any impurity represents distortion, and that means added harmonics that make very low ...

Many amplifiers, including integrated devices, are afflicted with undesired, implicit input terminals in their power connections. Due to less than perfect power-supply rejection, these implicit terminals admit noise into the signal that the ...

An audio volume-unit meter displays peak-related audio amplitudes to aid in accurately setting recording levels or for displaying an amplifier's operating conditions. A simple diode and capacitor network provides a classic volume-unit ...

Amplifying the human voice presents some tough challenges. One of the toughest of these is providing enough amplification to make sure a soft-spoken person can be heard while allowing sufficient headroom for people who speak loudly. If the ...

Class AB amplifiers have been the workhorses of the audio world, thanks to their simplicity, and their ability to deliver high power levels with low distortion. But there are also a number of gremlins that lurk within the AB architecture, mostly in ...

Class D audio amplifiers provide a dual benefit for battery-powered portable devices (Figure 1). They enhance battery life, and they produce much less power dissipation than do their linear cousins. Those features make Class D amplifiers ideal ...

The simple peak detector in Figure 1 is the result of a need for a single-5V-supply, level/clipping indicator for a multimedia-PC sound system. The design is unique in that it detects both stereo channels on a single peak-hold capacitor. All the ...