The circuit schematic below represents one method for the design on an audio mixer. The active component is an LM318, although basically any operational amplifier would work in its place. The circuit is the classic design for an Op Amp summing amplifier. Four individual audio channels are shown and may be mixed together. Channel D is really intend
Click here to download the full size of the above Circuit.
ed to show the addition of more channels and not used in the equation to calculate gain. The capacitors [C] are not used in the mixing function, but are there to DC block one channel from effecting another channel. The value of the capacitor should be selected so that it passes the signal of interest will little or no attenuation. In the case of an audio mixer the value should be selected so that it passes the audio frequency range. The value of each capacitor should be identical for each channel, otherwise an off-set in gain will occur between the channels. A common value found in one data sheet indicates a 1uF capacitor would work. Refer to Companies making Capacitors. A 0. 01uF capacitor is connected between the minus input and ground. The value of the potentiometer or adjustable resistor depends on the range of mixing desired and the values used for the other resistors in the circuit. Common potentiometer values include 100k and 500k ohms. A data sheet used 500k ohm values for each potentiometer. A decision also has to made regarding the style of tapper; a linear tapper or audio tapper. Refer to the Audio Amplifier topic for more information of using an audio tapper. The value and style of potentiometer should be same for each channel. Refer to Companies making Potentiometers. Note that most commercial mixing boards use a linear potentiometer which moves back and worth in a straight line, which is not the same thing as...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
characters left: