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A common collector amplifier with a 4.5v supply. The interesting thing is most of the things we learned in school turned out to be wrong for audio. The common collector amp worked the best for amplifying a signal sent to an actual speaker because(I think) of the low output impedance of that design.

The most important lesson was that audio applications do NOT like small caps. I wasn't getting any sound until I plugged a nice 470uF cap on the output, replacing the 10uF I was using(because that's what I normally use).

Audio is fun. Now tomorrow morning I get to go back to sinewaves in the 5Khz range.

*sigh*

(I made the speaker too. )

Congratulations.
The image is a bit blurry, but is it this kit?

thats awesome dude... now make a kickass distortion pedal =D hahaha

There used to be a company that sold plans for a nice distortion pedal. I think I found them about a decade ago in some guitar tab magazine of the time. The plans were cheap (less than $10 if I remember) and the parts cost less than that at Radio Shack (except for the box). The design used a single op amp.

This was before I got my degree, before I got online, and I have since lost the plans, but they may still be out there. However if you search google there are several circuits out there for this. Put one together and learn from it. Some nice sites are http://www.j.philpott.com/effectronics/, http://www.generalguitargadgets.com/ (look under effects projects), http://www.smallbearelec.com/home.html (under projects), and http://www.diystompboxes.com/.

As to what you learned in school being wrong ... well ....

Most circuit designs that deal with signal processing has instrument signals in mind.... scientific instruments, not musical or audio sources. So what you learned is probably correct.... for a different application.

Red: That's the kit, but I'm not using any of their designs -- I did those when I first got the kit, but I wanted to actually design an audio amp myself. That's why this is an achievement -- I could have followed the steps to wire up an amp back when I was six!

Cha0s: An amp without distortion is the hard part. Distortion is a piece of cake to get.

Distortion is easy peasy to do...electronic DIY style stuff hasn't caught on here yet, otherwise I'd do it myself - I've wanted to put a distortion control on my guitar itself - using the treble tone control of my strat to control gain...

Quote:Red: That's the kit, but I'm not using any of their designs -- I did those when I first got the kit, but I wanted to actually design an audio amp myself. That's why this is an achievement -- I could have followed the steps to wire up an amp back when I was six!

heh, I thought you were using the kit. The real accomplishment is building your own circuit which I haven't been able to do. I am dumb when it comes to electronics :oops:

SJ: I just thought I recognised the picture I'm planning to
(eventually) buy a electronics book + components, just too
teach myself more electronics than we get at shool...