The Blue Velvet Line Preamp with 7193 instead of 6SN7

[dwhitf]

The Blue Velvet Line Preamplifier
A DIY Project
Design by Dick Olsher and Kara Chaffee

The Blue Velvet Line Preamplifier

I have a stash of 7193s, I was thinking about using 4 of these instead of 2 6sn7s in the project.
I've been told the 7193s are like 1/2 of a 6SN7 with mu=20 and sound better than 6sn7.
Another option is two use 2 7193 in first position a one 6sn7 in the second position.

Your comments appreciated
dwhitf

[alexg]

I have used 7193 (mickey mouse tube) on a preamp a couple of years ago, and i cannot get rid of the hum.

A friend is quite successful on his 7193 preamp, it sounds excellent.