h2. here’s a valve based preamplifier in the works.
!http://www.mediumrecords.com/hacks/ecc83b-tb.jpg!:http://www.mediumrecords.com/hacks/ecc83b.jpg
those little glass envelopes can sure be fun… takes loads and loads of testing and tweaking at high-volume… but thankfully the neighbour has been pounding on the wall when the sound gets to be just perfect. (thanks bob.)
much of this stuff here has been salvaged from old television set and a bit of mysterious military transceiver equipment.
!http://www.mediumrecords.com/hacks/ecc83a-tb.jpg!:http://www.mediumrecords.com/hacks/ecc83a.jpg
there were some bad buzzes in there… on 1 channel but not the other oddly enough…
…dedicated powersupply with more current and cleaner power for the heaters was in fact the solution.
so now it’s 2 channels with the good kind of quiet. (and the nice wicked-loud i should mention)
only one mighty shock from the dc power so far… felt a bit like a pysio machine…
not so bad for 350 – 400 volts actually…
but do remember kids, involuntary muscle contractions can be dangerous… so play safe, etc.