Hello all. I'm doing a Physics project on how a Sound
System works electrically. I understand how an audio signal is transferred from a mic, how the volume is changed and how it is output through a
speaker. I'm having an issue understanding how an audio signal is changed, from an electrical stand
point, when it goes through an
equalizer. If anyone can offer an explanation it would be greatly appreciated!
Since this is for a Physics Project perhaps some research is in order?
Now sorting though hits on Google on this I am sure would be daunting to say the least, and be not at all helpful. There are several books that explain this very well, but I am going to guess that how EQ works may be a little over your
level right now. However with some research you can learn it.
Doing a Quick Google Search myself, there are lots of sites that talk about "how an EQ works" but NONE of them talk about how they actually work and the electronics behind them. However they are over the heads of most readers. Even the
Yamaha Sound Reinforcement Handbook Second Edition as I recall does not talk about this (however does tell you how electrically and acoustically much works very well).
Assuming you have the nessasary electronics/electrical background and knowledge with a little work you could look at the diagram of an eq or
console (eq on strip) and see the electrical components and see how they work.
I know I had some audio books that explained this but I think I lost them in the Tornado that ate my home and can't recall their titles.
Books and sources include:
READ THIS "
Equalizers and Phase Shift" - An article I just found that does describe some of what is going on.
An instructable on making a 3 channel EQ - This will be great for you. Shows you a great simple EQ curcuit (3 Channels!)
Electronic Devices (Electron Flow Version) Eighth Edition - FLOYD, has an entire chapter (chapter 15) on "Filters" so includes "Low Pass Filters" "High Pass Filters" and "Band Stop Filters" among others. Not a cheap textbook ($200) but perhaps you can find a source for it? Library?
HERE is a PDF of the 9th edition I just found...
http://en.wikipedia.org/wiki/Equalization_(audio)
The Wikipedia article does talk about to some extent how EQ works electrically.
Wikipedia Article on
"Electronic Filters" - another good start...
I hope this helps get you off to a good start. I'd also suggest talking with your physics teacher as he/she may be happy to help.