Here’s a simple audio mixer circuit that you can use to connect up to 4 mics on your amplifier. The potentiometers or volume controls are not part of the PCB to make it smaller.
Category: Audio
2.1 channel crossover circuit
2.1 Channel audio systems are so popular on most home sound system with low power output(usually below 50W). It only composed of left, right and a subwoofer speaker. The signal from the subwoofer is derived from both channels and filtered to output only the low frequency usually below 200Hz. Since the low frequencies are being produced by the subwoofer, it should be cut off on the main speaker.
DC Controlled Tone control
Here is another simple stereo tone control circuit. What makes it simple is that is uses a DC controlled tone control IC LM1036. The potentiometer act like a variable voltage divider and the output is fed to the IC that controls the level of Bass, Treble, Volume and Balance.
5 Band Equalizer Design
Here is a relatively simple 5 band equalizer that uses an IC LA3600 especially made for 5 band equalizer application. It has a relatively simple circuit that is easy for PCB layout. LA3600 make it easy to build your own 5 band equalizer with relatively few components. It will also be easier to design a single PCB since it only have very few components.
3 band tone control design
The tone control i posted last time was simple with only bass and treble control. it is also a mono circuit, you need to build two pcb to make it stereo. Now let’s build a little more complicated, a stereo tone control with mid control. If you haven’t tried building any PCB, I suggest try first the more simple tone control circuit. I will also include the simulation file just in case you want to change the response of the circuit.
Guitar Preamp Design
If you are a electronic hobbyist and at the same time a guitarist, this project is for you. I have seen many circuits of guitar preamp online but none of them gives you the PCB design and circuit simulations. I already made a version of this project years ago and it works. I also have included simulation files together with the eagle PCB files for you to download if you want to build this project. Take note that the capacitor sizes are not yet taken into account. You will need to edit some few capacitors like the C10 which will be bigger than it is on the board.
70W Car Amplifier Project
This circuit can actually deliver up to 70W at 4 ohms at 10% THD at 14.4V power supply which is very suitable for car audio applications. Make 4 of this amplifier and you will have a powerful 280W audio system for your car which will be very loud. Continue reading “70W Car Amplifier Project”
Guitar Preamplifier Circuit
If ever you want to build your own guitar amplifier, here’s the first thing you need to build. This is because guitar preamp are not usually sold as a kit unlike amplifiers. Guitar preamp are actually simple and usually consist of 2 stage, first – gain stage which amplifies the signal coming from the guitar and second – the filter stage which boost or cut frequencies that is determined by the user. Some preamp also includes effects such as distortion and reverb as the most common.
TDA7498 – 200W class D audio amplifier
Many years ago, it is not easy to build a powerful audio amplifier. You will need big power transistors with massive heavy heatsinks plus a heavy transformer too. It will also require a lot of efforts to build it, from drilling the heatsinks and connecting those wires. It is a very tiring task. Today a 200W amplifier can be as small as your mobile phone. Thanks to the evolution of Class D audio amplifiers. Smaller and more efficient amplifiers are now possible.
Electronic Audio switch with crossfade
Often times we used a simple toggle switch to switch between audio source. This is the easiest and simpliest method. But this simple circuit creates some clicking or boom sound when switching audio sources specially when the 2 audio source are operating. Here’s a simple and effective circuit to switch between audio sources gently. It gently decrease the volume of the audio source previously selected and while slowly increasing the volume of the selected audio source.
