A power sequencer is useful for audio systems where you can power up each equipment one at a time in sequence. This will prevent pop sound on the speaker during powering up or down. Basically the power sequence is from input to output when powering up and output to input when powering down.\
Continue reading “Power sequencer using arduino nano”Category: audio-others
Monitor Mixer with DI Box

One of the problem for low budget band online streaming is the mixing part. The biggest challenge is getting the mix right. Why is it hard? Guitar and other instruments have their own amplifier so when you are doing the mix, you would likely decrease the level of these instruments to the main mix. If you are feeding the main mix into your online live feed, chances are these instruments are too silent on the main mix.
This circuit can be use as a headphone amp mixer with built in DI box so you can directly feed the output into the mixer. There are 2 volume knobs, one knob is used for your instrument volume and the other knob can be used as a monitor level feed from the mixer.
Continue reading “Monitor Mixer with DI Box”Cheap DIY USB Audio interface for online streaming
In this new normal, most people shift to online content like seminars, meetings and specially churches.
Here is my current project designed to give you better audio for online streaming. It is basically a link to your analog mixer to your computer. It is also known as USB audio interface. What made it different to other products in the market is the integration of sliding fader for better volume control. For church online streaming, you have big volume difference between the band performing and the pastor preaching, the sliding fader makes it easy for such volume adjustments.
Continue reading “Cheap DIY USB Audio interface for online streaming”iRig Audio interface tear-down
Out of curiosity, I tear-down this iRig audio interface that I used sometimes to record my guitar solo. I didn’t expect the circuit to be complex since this device is cheap (must be fake), only cost around $3.
Continue reading “iRig Audio interface tear-down”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.
DIY Loud Bluetooth Speaker for your car
Building a bluetooth speaker nowadays won’t require so much technical knowledge. You just need to know how and where to connect wires. You can now buy a bluetooth receiver with a built in amplifier online and make your own audio system for your car for cheaper price.
WHY DIY(Do it Yourself)?
Some cheap car amplifiers on the market is not honest on their advertised power, these are very common to cheap and not so known brands. By doing it yourself, aside from getting cheaper, you can also be sure that your amplifier has the right power you need.
Simple DI box
Last time I have featured an active Di box circuit. Here is a more simple circuit that only uses 1 JFET instead of an OPAMP.
This circuit is so simple that you can actually build it without PCB. You can also just use a universal board on this one. I actually copied this circuit from an acoustic guitar. haha! sure it works and I also have simulated it.
Audio Mixing Tips
I have been mixing church sound system for quite a while now and I have encountered so many problems and solved most of them. On this article I will share tips to make your sound system sound best.
Most church sound system most challenge is the very tight budget. Very tight budget leads to very cheap sound system and leads to poor quality. Taking into account that most church sound techs are not knowledgeable enough for the job which leads to less optimal sound quality the system can deliver.
On this tips, I will assume that you already know how to operate a mixer and the whole sound system and you already have a sound system in place. I will create a separate post on Mixer 101 and choosing a right sound equipment.
Starting a Mix
So what to do after you have set up and turned on your system? Set the volume of the amplifier to 50% or less. This is to have maximum signal to noise ratio on the line. Setting the volume of the amplifier close to 100% will led to lower signal level and that level may close to the noise level. Take note also that when you set the volume of the amplifier to very low, the tendency is for you to crank up the volume of the mixer and may lead to signal distortions. Set the main volume of the mixer to unity gain(0dB) or just below the maximum. Adjust this when necessary on sound check.
Avoiding Feeback
One way to avoid feedback is to properly hold the mic(above picture). Holding it on the diaphragm(head) will introduce feedback at some conditions. It is like increasing the sensitivity of the mic so it introduces feedback. More information on this Article link here.
–More to come…
Audio Distribution Amp Project
Audio distribution amplifier is used to connect 1 audio source to multiple amplifiers. The circuit design is simple, they are basically a buffer circuit, meaning they are a operational amplifier with a gain of 1.
E-Gizmo FM transmitter
I was looking to have a wireless stage audio monitor and I was researching how can I be able to do that with less cost. Then suddenly I realize that most of the cellphones today have FM radio built-in so why just take advantage of it? The idea is simple, connect a FM transmitter to the audio mixer and use your phone’s FM radio to listen to the sound from the mixer. tadaaaa! you have an instant simple wireless monitor!