I've just bought a Laney VC30. So how long i should let the thing warm up before driving it hard?

And recommendations for a new set of valves would be helpful. I need a sort of gritty tone.
You really don't need to let it warm up, it won't damage the amp, just cut down your tube life.

But, for letting it warm up, a good minute or so should be fine unless it's really cold in the room.
Quote by Dave_Mc
I've had tube amps for a while now, but never actually had any go down on me
Quote by jj1565
maybe you're not saying the right things? an amp likes to know you care.

If you want a gritty tone, I'd recommend some sort of solid-state dirt pedal.
A metal band?
A Guitar with an LFR > Korg Pitchblack > Behringer EQ > Hardwire CM-2 Overdrive Boss SD-1 > Hardwire CR-7 Chorus>
Orange Tiny Terror >
LzR Engineering 212 cab

My other amp can run Crysis
Let 'em warm up for about a minute. Look at the tube sticky on top of this forum. Use it as a general idea, not a set in stone type thing. Read the goddamn stickies PLEASE.