Your Blackstar has no break-up?
I thought that's what people bought Blackstars for.
To me, that would be like someone saying that they use a Pignose for cleans.
Well not quite!
It is true that when the HT-5 was first released everyone and his dog loved it (it was the first new 5 watter for many years and was moreover a "proper" guitar amp, not just "two tubes and a tone pot"! Others soon got on the 5watt bandwagon)
Soon of course, being a British design and a runaway success, it had to be knocked by the home guard. "No clean volume" was the criticism. It's only FIVE watts FCS into a decent but not 100dB/W Celeston 10 incher!
The five is clean enough for its intended use, bedroom or studio and you can get pre amp distortion at any volume and output stage distortion if you want it. Being fixed bias push-pull, if you drive the beans off the 12BH7 the amp delivers nearer 10 watts and is therefore pretty loud. Quite a few people gig one into a V30 4x12.