Blackstar HT20R MKII 20 Watt 1x12 Tube Combo With ReverbEL84s are at the tonal heart of the HT 20R MkII combo and head. We have used our decades of valve amp design experience to combine the response and character of this classic British valve with a carefully voiced preamp to create wonderfully lush valve tones. From pure boutique cleans, to mild overdrive that cleans up by backing off the guitar volume control, right up to saturated distortion, this amp does it all.