Audio Mixer | Electronic Project Circuits

Posts Tagged ‘audio mixer’

Bass Boost section + Output Driver With IC

The Bass Boost section provides two switchable levels of Bass enhancement. The input audio is first low-pass filtered by a second-order LPF, whose cutoff frequency is 100Hz. The LPF is built around IC2C and IC2DThe output of the LPF is given to a MUX based on a CD4052. This mux can choose between ground, an attenuated version of the LPF, and the full LPF output. The selected MUX output is summed with the original audio, yeilding a Bass Boosted signal. The outputs of this section are fed to the final power stage.
The trimpots R21 and R25 are used to set the bass level for the low-bass mode. This is usually not just the midpoint (50%) level, it’s somewhere like 70%. It can be adjusted to personal taste. IC2A and IC2B act as the summing amplifier and output stage driver. 100Î© resistors R11 and R16 are used to prevent the load capacitance from causing instability in IC2A and IC2B. 2Î¼F coupling capacitance is provided.

Source:http://wiredworld.tripod.com/tronics/mosfet_amp.html
thank you.

Be the first to comment - What do you think? Posted by admin - September 13, 2007 at 5:18 pm

Categories: Pre Amplifier, Tone control Tags: audio mixer, bass boost circuit

6 Input Mixer by IC 741 , LF351 ,TL071

Description:
A simple mixer with 3 line inputs and 3 mic inputs using commonly available parts.

Notes:
The mixer circuit below has 3 line inputs and 3 mic inputs. The mic inputs are suitable for low impedance 200-1000R dynamic microphones. An ECM or condenser mic can also be used, but must have bias applied via a series resistor. As with any mixer circuit, a slight loss is always introduced. The final summing amplifier has a gain of 2 or 6dB to overcome this. The Input line level should be around 200mV RMS. The mic inputs are amplified about 100 times or by 40dB, the total gain with the mixer is 46dB. The mic input is designed for microphones with outputs of about 2mV RMS at 1 meter. Most microphones meet this standard.

The choice of op-amp is not critical in this circuit. Bipolar, FET input or MOS type op-amps can therefore be used; i.e 741, LF351, TL061, TL071, CA3140 etc.

Source :: http://www.zen22142.zen.co.uk/Circuits/Audio/6ipmix.htm

Be the first to comment - What do you think? Posted by admin - June 25, 2007 at 1:26 pm

Categories: Audio diagram, Pre Amplifier Tags: audio mixer, LF351, Microphone preamplifier, TL071

Stereo Mixer

With this circuit you can mix four separate audio inputs. Each input will accept high or low impedance microphones, phonograph, tape or aux signals. You can adjust the gain of each input by adjusting each respective pot. With the Stereo/Mono switch you can combine just inputs 1,2 and 3,4 or in the Mono position combine all four inputs. Signal response is 20 Hz. to 20kHz. with very high input impedance and very low distortion with complete output short circuit protection. This circuit will drive any power amp with an input impedance of 2,000 ohms.
And you can read more about LF353 here.
From : http://home.maine.rr.com/randylinscott/may20.htm