Blackstar is a relatively new British company, launching in 2007, that boasts an R&D and engineering team that cut its teeth with perhaps the biggest amp name of all time: Marshall. Breaking out on their own in this new venture, Blackstar has its own range of range of amps as well as various valve-driven pedals. They're all devoted to that most satisfying of pursuits: distortion and drive.
The pedals share various features. Each is loaded with a single Russian-made ECC83 dual-triode preamp valve, backlit to glow red. More interestingly, that valve runs off a full 300-volt circuit, (hence HT in the name: HT for 'high-tension' meaning high voltage). This is thought by many to offer better tone, gain and overload characteristics than low-voltage valve pedals. After that, all except the HT-Boost offer a speaker-emulated out alongside the regular output for a direct-to-desk recording option, and finally, three of the quintet are loaded with what's called an ISF (Infinite Shape Feature) control. Unlike more familiar contour circuits, this enables you to move the entire EQ section voicing between what you'd expect of two classic amplifier tone circuits: Fender at one end and Marshall at the other.
"The ISF came about because we were looking for a way to voice testbed amplifiers for artists," explains Blackstar's technical director, Bruce Keir. "We needed a way to continuously vary the tone beyond what was available from existing amplifiers. This would enable the player to create their signature sound before we 'locked it off' in their preferred setting. The method we came up with gave the ability to not only get the standard reference tones, but also the 'in-between' never-before-attainable voicings as well. It worked so effectively and so simply that we decided to make it a feature available for all guitarists to use." Indeed, the ISF control broadly apes the tonal response of classic 6L6- or EL34-powered amps, plus many points in between. You'll find the other pedals reviewed on MusicRadar, but here we have the HT-DistX DX-1
The legend 'pure valve filth' leaves you in no doubt as to which styles are best suited to this pedal. Although bearing exactly the same layout as the HT-Dist, this unit is designed to be hotter than the slopes of hell on a July afternoon...
Even with the gain set to just past one there's plenty of the stuff on offer. Wind the wick further and the tone squashes and cascades, yet maintains dynamics and a notably big, amp-type feel for a pedal.
The most metal-esque scooped tones are with the ISF all the way clockwise, due to the more apparent bottom end. Reduce the middle, add as much bass as you can without 'woofing' and set the gain to just over half: that's where that lovely James Hetfield crunch is to be found. The more the ISF turns anticlockwise, the more focused and cutting the tone becomes. In fact for all modern styles, including tuning our guitar all the way down to C, the HI-DistX remains clear, musical and earth-shatteringly heavy.