Experience the next generation of affordable tube tones with theHT-5RH MK IIIfromBlackstar, a 5W amplifier head ideal for home practice, recording, and band rehearsals. Sporting one ECC83 tube and one 12BH7 tube, along with two channels, two voicings per channel, and patented ISF control, you get generations of tube tone at your fingertips.

With power reduction down to 0.5W via controlled reduction of internal working voltages, you can enjoy more freedom to push your amp without disturbing your neighbors or sacrificing sound quality. The amp includes diverse output options, with XLR, 1/4″ headphone, and USB supporting Blackstar’s innovative CabRig speaker emulation, a series FX loop, and more. The USB-C port offers 2×2 interface functionality, allowing you to enjoy a rare marriage of vintage tube tone and modern digital versatility.

HT MK III Series Ethos

When creating a series of amplifiers, the traditional approach would be to start with a preamp design and then bolt this on to a range of power amplifiers of different power ratings. However, Blackstar acknowledges the interaction between preamp and power amp and the individual requirements that different amps need.
Therefore, although the preamps do share many similarities, each and every model has had the same individual care and attention during sonic testing, and any required tweaking of the circuitry has been applied to ensure each model performs to Blackstar’s high tonal expectations.

Clean Channel

The MK III Clean channel is a very sophisticated circuit, albeit deceptively simple looking, that is extremely versatile for producing a range of classic clean and crunch tones. The two different voicings use both parts of an ECC83 (12AX7) tube exclusively for producing compression and crunch.

Overdrive Channel

The HT MK III overdrive channels are the next in an evolution from Series One, HT MK I through to HT Venue MK III. The topology shares the same basic building blocks in the gain structure and tonal shaping and includes the cascaded gain stages of an ECC83 double triode valve. However, each amp has had the overdrive tones specifically tweaked, tuned, and refined during hours of listening tests, to optimize the tone for that model.
An important aspect of the Overdrive channels is how well the tone cleans up when the guitar volume is backed off. In conventional valve-amp designs, the treble response of the overdriven sound is shaped by a series of cascaded first-order low-pass filters placed between each of the valve stages that are being overdriven, which often leads to a droopy filter response and a dull or lifeless backed-off tone. In the HT MK III Overdrive channels, the majority of the high-frequency shaping of the distortion is done using a second-order low-pass filter. This has the advantage of removing unpleasant high-frequency fizz without attenuating the signal below the cut-off frequency.

Patented Infinite Shape Feature

The conventional three way guitar EQ network, or tone stack, is a key to the characteristic voice of traditional guitar amplifiers. Classic amplifier designs have their own versions of this network, which leads to their own tonal voicings.
The passive ISF control allows you to infinitely adjust the response of the tone control network between any of the traditional voicings in a way that has never before been possible, for everything from a classic American to vintage British tonal range. The ISF control is interactive, moves the whole tone stack at once, and is continuously variable.

Clean Voices

The Voice 1 setting (LED off) has been based on a classic American clean sound, a mid ’60s black-face Fender Twin Reverb. This setting provides high headroom and a bright and clean sound with solid low end.
The Voice 2 setting (LED on) has been based on a much loved vintage Class-A British tone (Vox AC-30). The gain structure is reconfigured to put the EQ shaping after both the valve stages, and the power amp is set to have no negative feedback. These and other carefully voiced parts of the circuit result in a warm tone with a chimelike top end and relaxed resonant bottom.

Overdrive Voices

Switching to Voice 2 (LED on) on the Overdrive channel will add more gain for the overdrive and reduce the power amp damping, giving livelier highs and more resonant lows. Overall this changes the character of the overdrive from a classic tone to a higher gain, more contemporary tone.

Digital Reverb

While a traditional, possibly old fashioned, spring reverb is often a choice for tube amps and can be great for Fender-style clean tones, Blackstar felt this wasn’t the best choice for modern overdrive tones. So they developed their own digital reverbs specifically voiced for both clean and OD tones.
These exclusive Blackstar designs respond well to both the dynamic nature of clean sounds and the more compressed, harmonically rich textures of crunch and high-gain overdrive sounds. In addition, the Reverb Time can be adjusted for Clean and OD channels independently using Blackstars Architect software. This level of choice and flexibility simply would not be possible with a mechanical spring reverb.

Features:

• A 2-channel, 5-watt update to Blackstars lauded HT-5RH amplifier platform
• Clean channel offers superb clarity and definition
• Extensive overdrive channel includes a 3-band EQ and ISF control to cover everything from classic American grit to all-out high-gain British firepower
• Both the Clean and Overdrive channels feature their own dedicated Voice control to switch up your sound
• Onboard reverb imparts a sense of space and air to your tone
• Effects loop with a +4dBu/-10dBV switch allows for easy integration of your time-based and modulation stompboxes
• USB-C, balanced XLR, and -inch outputs equipped with Blackstars innovative CabRig speaker emulation technology
• USB-C offers audio interface functionality for easy mic-free recording
• 0.5-watt power scaling is ideal for late-night jamming, quiet recording, and any other situation where volume is a concern

Specs:

• Type: Tube
• Number of Channels: 2
• Total Power: 5W RMS (0.5W setting)
• Preamp Tubes: 1 x 12AX7
• Power Tubes: 1 x 12BH7
• Reverb: Digital Reverb
• EQ: Tone, 3-band EQ, ISF Control
• Amp Modeling: American, British
• Inputs: 1 x 1/4″ (instrument), 1 x 1/4″ (line in)
• Outputs: 1 x 1/4″ (8 ohm) 2 x 1/4″ (16 ohm), 1 x XLR (line out),
• Headphones: 1 x 1/4″ (phones, line out)
• Effects Loop:Yes, adjustable level
• USB: 1 x USB-C
• Footswitch I/O: 1 x 1/4″ (channel, voice)
• Footswitch Included: No
• Computer Connectivity: USB
• Features: CabRig DSP Cabinet Simulation
• Software: CabRig, Architect
• Construction Material: Black Tolex
• Power Source: Standard IEC AC cable