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Simple 555 based Tremolo Effect Schematic

As of now here's a quick schematic for the video shared on Reddit (post embedded below!). I will re-wrote this post in detail when I have time.
Reduce the value of C1 for faster tremolo or turn the potentiometer! You can remove D1 once you've finished testing. The way in which circuit works is quite simple- The 555 produces a square wave in which the ON time is greater than the OFF time, this signal is inverted by an NPN transistor in the next section. And then finally, whenever the last LED(D2) glows, the LDR's resistance decreases and almost shorts the signal creating a superb tremolo effect!


Simple Tremolo Effect using 555 and coupled LDR-LED ! from r/diypedals
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15 Watt Guitar Amplifier using the TPA3118 Module

Recently, my Roland-cube amplifier decided to stop working amidst the pandemic. So I put together a simple amplifier to continue playing guitar during the lockdown. 


Loosely speaking, every guitar amplifier has three stages- A preamplifierEffect processorPower AmplifierOf the three the effect processor is kind of optional, especially, if you always use your amplifier with a pedal or a processor. So what are these three stages exactly?
Here's a quick idea-  The signal coming from the guitar is a very weak AC signal having a maximum amplitude of a few millivolts.
The Preamplifier: Before you can add any effect to this weak audio signal, the signal current and voltage of the signal need to be amplified a little bit to ensure there is minimal loss of the signal in the further processes. In many cases, the pre-amp leaves the voltage untouched, and only amplifies the current. This kind of circuit is called a boost or buffer circuit.
The Effect Processor: Now, the signal from the preamplifier …

Reading between the lines- Zoom G1Xon Guitar Pedal Oscilloscope Plots

Lately, I've been working on a programmable guitar pedal, which involves electronic-tweaking of sound signals produced by a guitar. This time, I chose a rather more engineering-oriented approach involving a bit of research and data collection instead of directly sitting down to design a pedal. Observing the master's work is always a great place to start learning a new concept!

While I've watched several demonstrations and used several unique guitar pedals and made some myself that produce the craziest of sounds, I've always wanted to understand the effects through a more visual representation.

And so, I hooked up a simple setup involving a guitar pedal, an oscilloscope, and a function generator to see how a digital guitar pedal manipulates a clean input sinusoidal signal. Afterall, an audio signal is nothing more than several superimposed sinusoidal waves with different frequencies (Fourier series).

Equipment Used- Guitar Pedal- zoom-G1xon Multi-effects digital pedal Oscill…

How are capacitors used to filter noise? [A unique explanation]

If you have worked with guitar pedals and audio circuits in general, you may already know how capacitors are used as low/high pass filters. While designing non-distortion guitar pedals (tremolo, reverb, delay, etc.), a designer uses capacitors in some way or the other to make sure that all the amplification and equalization does not bring in any sort of distortion.




The question is how do you filter out distortion?

This article is about one of the most exciting concepts that exploit the beauty of science and math to provide an altogether new way of thinking about circuits.

Before I actually come to the 'aha-moment', I'd like to make sure everyone reading this article is on the same page. 
If you are already good with low pass filters you can skip reading till you see a bold blue text that says 'skip till here'.
What you see below is called a low pass filter circuit (or to be more precise a passive low pass filter circuit).





Such a filter circuit allows low-frequency signal…

Distortion Pedal Electronics (Explained for beginners!)

If you are into DIY guitar pedals and want to start designing your own effects, this article might help you open a few doors. I write this article as an EE student who earlier struggled with understanding these circuits and would often simply copy schematics off the internet. 

This article is intended for-
1. Absolute beginners who like tinkering with electronics
2. Anyone who has been learning analog circuits and is looking for a jumpstart project.

Also before I start I'd like to mention, for anyone who wants to get a rock-solid foundation in Analog electronics, I highly recommend reading the book, 'Electronic Principles' by AP Malvino and David Bates.

Distortion Pedals come in all flavors and sizes, however, how the distortion effect is achieved in any of the pedals is more or less similar. Let's first see how the output of the pedal compares to its input.

The raw signal coming from the guitar is first amplified a little, and then the peaks of the amplified signal are clip…