You should decide the order of the filter and choose a suitable capacitor and resistor by calculation based on frequencies above



Module Details

Module Code

23 FEB

Module Title
Signal Processing and Circuits

Module Leader

Module Tutors

Component and Element Number
Component: CW (Group Assignment)

Weighting: (% of the Module`s assessment)

Element Description
Small Scale Project

Total Assignment time
9 hours


Date Issued to Students


Date to be Returned to Students

Submission Place:

Online Via Moodle

Submission Date
21 May 2023

Submission Time
Before 4:30 pm


Attached sheet details deliverables.

Module Leader Signature

Nemat Elhassan 

 Seven-Band Equalizer  

Equalization means attenuating or boosting the levels of different frequency components of a signal. Equalizers can be Digital or Analog filters that adjust the loudness of specific frequencies; based on the human ear hearing range (20-20,000 Hz).

To design an n-band equaliser; the whole bandwidth of the equaliser is divided into n frequency bands, which can be individually amplified. An n-band equaliser is implemented using a low pass filter, a high pass filter and a set of n-2 band pass filters. Very simple 3-band or 7-band equalisers are found in nearly every modern hi-fi system.


The objective of this project is to build a seven-band equalizer. The equalizer is a hardware filter intended to adjust the volume of specific frequencies of an audio signal. The adjustment works on the audio supply by either increasing or cutting off certain frequency ranges. The purpose of an equalizer is to make the sound louder or softer by varying the notes, or it can keep the same sound of the original.

Project Goal : 

The project goal is to design a seven-band equalizer. In the first stage, the equalizer has an audio input, which goes through filtering circuits, and each band of the filter has an output that can cut or boost the high and low ranges. In the second stage, the result of summing the signals comes to the output jack, which is connected to a pair of speakers or headphones. To have a more professional and customizable sound, the equalizer provides control of 7 bands to accommodate for the wide range of human hearing spectrum.  

Figure 1: 7- Band Equalizer Block Diagram

Practical Design Aspects:

Building a seven-band equalizer requires seven separate filters, each with a different center frequency. The seven-band equalizer must utilize multiple feedback (MFB) bandpass filters. The frequencies are based on industry-standard values and the frequency peaks to be detected are as follows: 63Hz, 160Hz, 400Hz, 1kHz, 2.5kHz, 6.25kHz, and 16kHz

  • You should decide the order of the filter and choose a suitable capacitor and resistor by calculation based on frequencies above
  • Simulation using suitable software such as NI Multisim or Proteus 8 Professional.
  • Plot frequency response for each filter
  • Building circuits on a breadboard and/or PCB and testing real audio signals using oscilloscope.

Deliverables :

You are required to submit a group-written full report on the design and development of your project. This should be word-processed and professionally presented (5000 words excluding references and appendices). Concise means that everything about the project and how it was done, should be presented in as few words as possible (do not just write a lot to impress). 

All notes, calculations, schematic diagrams, measurements, and observations must be submitted by each group of students, in a concise and professionally presented document. 

However, an index will be required. It should include all the info you have used, with references to data sheets (not the whole data sheets themselves), the calculations, the circuit schematic, and maybe the component layout. Should be included the circuit description, as well as the observations and results of testing. 

A contribution table listing the individual tasks carried by each member of the group is to be included for individual marking purposes. Acknowledgments, sources of help, and perhaps photos too. Everything should be submitted in a clear folder with students’ names on it.

The circuit simulation file is also to be submitted with the project report.

General Instructions

  • You are required to work in groups of 6 students and submit one final report, and simulation file. It is your responsibility to choose your group members.
  • Both simulated circuit and physical circuit will be tested with an audio signal as the input. The output signal is to be connected to speakers and an oscilloscope as well, to test the frequency response.
  • Your design should be innovative in its minimal component count thus keeping down the ultimate cost of production. However, the quality of performance must be maintained as well. You must justify your choice of filter circuit design and it must be suitable for the application.
  • It is your responsibility to complete your project on time and DO NOT WAIT till the last date of the submission. 

Marking Scheme:




Final Report     


Diagrams/Schematics/Bode plots    


Written description


Calculations & Discussion


Design approach & Novelty/Economy of components


Circuit Build    

Operational & Fit for Purpose


Responds to frequency bands designed


Professionally built




Total Marks



As this is a group assignment no late submission will be accepted.

100% Plagiarism Free & Custom Written, Tailored to your instructions