[sdiy] tube preamp? / cheap board

[Henry]

Hi Folks, Joe,

>After doing some research, I would like to preamp with tubes, but can't
find any >good (inexpensive) kits for a tube preamp.  I think I may go with
the PAIA riaa >phone preamp, but not sure how it will sound.  Any
suggestions?

Yep.  Buy a bipolar transistor front end based design and turn on a 100W
heater next to it.  The noise, hum  and distortion will be lower and you can
still keep warm.  Douglas Self seems to speak quite knowledgably on the
subject in his book on audio, (see Amazon) and he tests his designs
carefully with the appropriate gear, from what I've read.

Separate point...

There is an old supplier of surplus electronics equipment in Hove, Sussex UK
who are currently advertising stocks of some old keyboard units.  They
consist of three octaves of full-size keys in a fairly substantial box.  I
bought a couple of these recently out of curiousity and they turned out to
be ones originally used with the Sinclair ZX spectrum, and have a bit of
electronics inside to interface with the old dear.

The keys themselves are cheap but usuable closing contact types, though
unfortunately they do not have double closing contacts, so you'd have to use
some imagination to generate a gate signal, or frig something inside to
double them up. (He does cheap microswitches too - 10 for a quid) All the
same, at £15 for two they could easily be made into a cheap CV source for
the workbench with a current source and some resistors.  The phone number is
01444 881965 or email jnfactors at aol.com.  He has stocks of unused Hivac XN11
nixie tubes too.  (I have no connection with the company - so don't blame
me:)

Henry.

www.monumentaltat.co.uk