Yes you can and I did.
I've had only tubes in my system up until about 4 years ago. The cost to retube an amp and the cost to purchase a new tube amp over 100 watts made me look at SS. There are a few amps out there like Moon and Pass that come close to tube sound, look around. I am staying with a tube Preamp though, I feel there is a large differance in the sound compared to SS and the cost to retube is minimal. So keep your tube preamp.
I've had only tubes in my system up until about 4 years ago. The cost to retube an amp and the cost to purchase a new tube amp over 100 watts made me look at SS. There are a few amps out there like Moon and Pass that come close to tube sound, look around. I am staying with a tube Preamp though, I feel there is a large differance in the sound compared to SS and the cost to retube is minimal. So keep your tube preamp.