• Category Archives audio
  • VS 2121 Autopsy

    I was given an Altec Lansing VS2121 powered speaker sytem that was going bad. And I wanted to recycle some of the parts out of it. What I found inside was quite interesting.

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    Here is what I found,
    2 x lm324 quad op amp from st
    2 x tfa9842j single chip 2 channel amp
    and a whole bunch of passive through hole parts (caps, resistors) .
    It is a very simple design. Now I have some decent op amps and a decent size transformer (120v to 15.3v 1.6A) with a nice particle board box.

    Time to start thinking of what I can remake this into.
    Happy Hacking!


  • Experiments in Home Audio (lm386)

    I really needed a quick amplifier to power a few book shelf speakers. Looking around my ic bin, I found a few lm386s.
    Next I pulled the rest of the parts (1x perf board,  2x ic sockets,  2x 100uf caps, 2x 5k pots,  some wires,  and a few odds and ends) 

    Put all this in a blender, bake for few hours and this is what you get.

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    The results are,  its not  a bad sound. some noticeable distortion at higher levels. More improvements can be made, like changing the output caps to bigger ones,  adding a gain selector….etc.
    But what I have now works. Next a class A amp and other projects.