Circuit Lake » Audio

PIC Tremolo Guitar Effect

admin — Mon, 26 Jul 2010 01:00:02 +0000

The dsPIC33FJ64GP206-based Ultimate Tremolo is a DSP-based guitar effect pedal that gives the user complete control of every parameter of the tremolo (or amplitude modulation) audio processing effect. This is accomplished by interfacing the pedal to a PC via a Microchip PIC18F4455 USB-enabled microcontroller and editing the settings through software rather than the normal [...]

Home-made Sound Card Interface

admin — Fri, 26 Mar 2010 23:38:36 +0000

The PSK31 (Phase Shift Keying, 31 Baud) Adapter is a hardware interface between a PC running a digital communications program, such as DigiPan, and an Amateur Radio transceiver. The electronically adjustable PSK31 interface is controlled by microcontroller AVR ATmega8. It provides automated adjustment and optimization of the audio levels that are carried between the [...]

Voltage Controlled LFO

admin — Fri, 15 Jan 2010 21:19:54 +0000

Low-Frequency Oscillation (LFO) is an audio signal usually below 20 Hz which creates a pulsating rhythm rather than an audible tone. LFO predominantly refers to an audio technique specifically used in the production of electronic music. Ray Wilson designed nice Voltage Controlled LFO (+/-12V to +/-15V) for your modulation needs. In this project, the frequency [...]

Digital Subwoofer Amplifier with Feedback

admin — Sat, 09 Jan 2010 22:07:13 +0000

The project used interesting approach for reducing speaker distortion and increasing bass response. A dual coil speaker driver is used but only one of the coils is connected to the power amplifier – the other is used for electromotive feedback. This method is not new, but is difficult to implement in pure analogue world because [...]

Audio Spectrum Analyzer

admin — Mon, 04 Jan 2010 18:38:33 +0000

Spectrum analyzers are employed in most of the modern signal processing systems for measuring the distribution of signal energy in frequency. An audio spectrum analyzer is used for measurements in the audible frequency spectrum (from 0 to 20000 Hz) and can be a very powerful tool for keeping a studio well tuned. A Digital, real-time [...]

AVR Digital Signal Processing

admin — Sat, 12 Dec 2009 20:10:31 +0000

This project is an experiment of the Digital Signal Processing based on microcontroller AVR AtTiny 26 instead of an ordinary digital signal processor. The project used as simple audio signal processing. There are some simple audio processing, such as Delay, Echo, Pitch Conversion, that easy to experiment with the project. The microcontroller samples input signal and [...]

PIC Controlled Hi-Fi Preamp

admin — Wed, 02 Dec 2009 01:53:42 +0000

The aim of this project was to add remote-control convenience to the hi-fi preamp without compromising sound quality. It replacing the existing volume control with high-quality optical rotary encoder controlled by PIC 16F877. The project has 7 input sources and 5.1 surround sound. Features: High quality, clear and easy to read VF display. Volume control is [...]