[sdiy] Hollow low-pressure ladder filter

[epeasant at telusplanet.net]

Hey Tim,

>Yo,
>
>My 6AL5s finally arrived. Tomorrow, neurons willing, I
>will bang together a diode version of a ladder filter.
>The advantage is: no high voltage. +/- 15V should be
>enough to run it.

With a forward voltage drop of 10 volts each, won't at least 70+ volts be required
for a stack of 5 6AL5s, or am I missing something here? You will save money
on sockets, however, minature 7 pin sockets are cheaper and easier to find than
miniature 9 pin sockets. ;-)

>Now for the bad news: the 6AL5s are military tubes. So
>any music mafe with this filter will come out sounding
>like a march  ;-)
>

Naw, it will just sound a bit more regimented!


>More 12AU7s and filament transformers are on the way
>for the triode version. Or should I use pentodes to
>satisfy those ultra-linear purists out there?
>

Maybe try 6AU6s, they are cheap and plentiful pentodes.

When you get the ladder working, you should then try to replace the rest of
the solid state parts in the signal path with tubes.

Take care,
Doug

______________________
The Electronic Peasant

www.electronicpeasant.com