Help needed with HT 5 mini stack

[crazy chester]

Hi all new member here!
Brief background, I had a ht5 combo a couple of years ago and sold it (regretted it ever since!) so I wanted to purchase another one and I got a good deal on the mini stack second hand but...... I thought that the stack version, with 2 cabs would be a bit louder than the original combo I had but as it turns out there is LESS volume with the stack compared to the combo! So the question I ask is, could this be a valve problem? (Are the valves old and the lack of volume is a sign of this) or is this a common fault with the ht heads? If so, has anyone got a fix for it??
Really love the amps but need a bit more omph out of the rig!

Kindest regards fellow blackstar owners!!

[thephantum]

My HT-5RH is pretty loud, so my guess is that yours is not any quieter than the combo. You are just putting less power to each speaker so it seems that way. With the combo, you have one speaker taking all 5W. With the stack you have two speaker splitting that 5W...so 2.5W each.

If you've tried just one cab and you are sure it's quieter, it's possible that output tube needs replacing. It's also possible that someone replaced the tube and did not bias the amp. Contrary to popular belief, (and unlike the HT-1) the HT-5 does need to biased when you change the output tube.

[crazy chester]

Hi! Yes I've tried it with just 1 cab out of the 16ohm only output but it's the same. Single cab or twin cab it's still low volume...