Stereo Graphic Equalizer

Welcome to the website for the Stereo Graphic Equalizer project at Villanova University, part of ECE 4970. This website will contain information on the planning, progress, and results of the project.

Project Members

Project Summary

This senior design project will consist of the design, prototyping, testing, and production of an analog electronic-based 3-4 band graphic equalizer plus 2 watt audio power amplifier suitable for use with handheld audio devices with a standard mini-stereo jack. The equalizer would plug in between the portable audio unit and stereo speakers and would allow the user to adjust the frequency response to their personal preference. The students will test their circuit both in the lab as well as in a 'real world' sense by listening to the system in action.

The device built may have a separate low-pass output for use with a subwoofer. Since it is stereo, there will be two identical halves, one for the left channel and one for the right, with the equalization of each being synchronized. The primary mechanism for filtering will be 741 Op-Amps. The unit will be powered by battery or 120 V AC @ 60 Hz.

Project News

This section will contain a summary of our monthly/weekly progress reports.

December 2

ECE Day poster was a great success. Currently we are making preparations for final one-channel printed circuit board.

November 4

Poster (PDF)

October 28

Breadboard under test

September 23

Meeting scheduled, timetable established, simulations retrieved.

September 16

This past week we focused on reviewing active filtering techniques. We started with passive filters, their advantages, disadvantages, and how they affect the circuit overall. Although not having to supply power to passive filters makes them look advantageous at first, the overall versatility of active filters makes them much more valuable tools overall. Active filters can be designed to have high input impedance, low output impedance, and the gain can be adjusted during operation, which makes active filters the implementation of choice for our project. This research then brought to light the need for a power supply, and we discussed various sources of power for our project and the advantages and disadvantages of each. As there is no need to decide the source of power in this early design phase, we will not select a power source until later in the design process.

Today we had our first meeting with Dr. Caverly, and plan to meet every Tuesday.

September 9

Today this website was established, and relevant info posted. We have reread our proposal and are scheduling time to meet with our advisor and work on the project.

Rough Schedule

(all times is ideally by the end of the week beginning on the stated day)

Other Resources