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.
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.
Low Voltage Disconnect Circuit
Low Voltage Disconnect circuit are used to disconnect the battery to the load when the battery voltage drops to certain level. This avoids further discharging of the battery. This is very useful for devices that uses rechargeable batteries.
Arduino Solar Power System
I have featured several articles on solar power charging circuits, now I am actually making one for my home use. I am currently on works to develop this system, although I know the theories behind it, I still learned a lot in this process. This system will be used for cellphone charging and a small light.
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.
Simple Current Sensor for Arduino
There is actually a board that you can attach to arduino for measuring current but if you don’t need a very accurate measurement, you can use this very simple circuit. Usually a low resistance resistor is connected in series to the load. The voltage of the resistor is measured and divided to its resistance, the result will be current.
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”