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 look at HT-Drive OD-1.
This forgoes the ISF and three-band EQ featured in the rest of the range in favour of a simple tone pot. Blackstar calls the tone the 'A Class control', designed to retain the character of your chosen guitar, while still cutting unwanted fizz.
There's less gain here than in the previous pedals, but even with it set to zero, we're just the dirty side of clean for Keef-style rock'n'roll chords. Heading up to around 9 o'clock - still low - ushers in vintage-style drive, then onwards towards Clapton-style singing lead lines. Things can get harsh with single-coils, and rolling back the tone pot helps if you like it all smoother and rounder. Naturally, for a touch of zing for your Les Paul's neck pickup, turn it back up.
Adding a spot of dirt to the amp enables you to use the HT-Drive to smooth out your tone and add sustain. While you can use the pedal as a straight solo booster - there's tons of level here - lots of players will also enjoy the extra sustain and harmonics. You can get these on top of an already cooking tone, yet without sacrificing too much of your core voice. Even better, it all cleans up nicely when you roll back your guitar's volume pot. Despite its 'overdrive' name, there's still tons of gain in this pedal.
If you want to distinguish it from Blackstar's HT-Dist, the latter is somewhat smoother in a rock sense and also more versatile. Rootsier-minded players may well prefer the edgier, plug-and-play appeal of the HT-Drive.