Hell, yes, the Triwatt will do metal.
It has both the high end and big low end frequency response. Engage the Overdrive stage and it will give way more gain than a regular Hiwatt, with a distinctive edgy grind. For even more dirt, throw a Proco Rat or H&K Warp7 pedal in front. The power stage is tight, fast and snappy. Just what you need for metal. It's loud with the 6V6s, but with the 40W KT66 option and some good efficient speakers, it's way loud, and with an even bigger sound.
In the words of pro player Lawrence Bethune, from a review of the prototype Triwatt (with 6V6s), on
posting.php?mode=quote&f=14&p=13447 lbethune wrote:
I cranked everything with a Les Paul and immediate heard the metal gods commanding me to Thrash!!!