"Matisse" preamp - 12AX7 12AT7

don't have any : (
simple as that - I'd probably rather try the attenuator than hedge my bets on a new tube after so much experimentation to get the correct sound and then perhaps not even get the correct reduction in gain!

Feel free to talk me out of it though ; )

okay - ace. presumably I could run it with 4 matched 12AT7 instead, too. is there any danger to the circuit/power supply by running a non-specified tube? so many forums say yes, and and equal amount say no!

hmm could be the source, but how do I test? I have only one source, one pre and one power amp...

Okay that is good news, thanks guys. I will try it with a spare set of 12AT7 tubes (ie 4 12AT7 tubes) and let you know how it goes.

Okay well, to report back, I tried it and it did not really change much at all!!
I rolled in a few other sets of tubes to see if any differences could be noticed, and slightly less gain was apparent on the following combination;
Brimar CV4004, GE JAN 12AT7WC
This also sounds great (except for the first time I turned it on there was good deal of buzzing whilst turning the volume dial on low levels - although it went away after a while, any idea what could cause this?).

I will now head down the in-line attenuator path I think....