1. Introduction
This manual provides essential information for the safe and effective operation of your Blackstar HT20R MKII 20-Watt 1x12 Tube Guitar Combo Amplifier. Please read these instructions thoroughly before use to ensure optimal performance and longevity of your amplifier.
2. Important Safety Instructions
- Read these instructions.
- Keep these instructions.
- Heed all warnings.
- Follow all instructions.
- Do not use this apparatus near water.
- Clean only with a dry cloth.
- Do not block any ventilation openings. Install in accordance with the manufacturer's instructions.
- Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.
- Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades with one wider than the other. A grounding-type plug has two blades and a third grounding prong. The wide blade or the third prong are provided for your safety. If the provided plug does not fit into your outlet, consult an electrician for replacement of the obsolete outlet.
- Protect the power cord from being walked on or pinched, particularly at plugs, convenience receptacles, and the point where they exit from the apparatus.
- Only use attachments/accessories specified by the manufacturer.
- Unplug this apparatus during lightning storms or when unused for long periods of time.
- Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been damaged in any way, such as power-supply cord or plug is damaged, liquid has been spilled or objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not operate normally, or has been dropped.
3. Product Overview
The Blackstar HT20R MKII is a versatile 20-watt tube combo amplifier designed for guitarists seeking a wide range of tones. It features two footswitchable channels (Clean and Overdrive), each with two voices, and a powerful EQ section including Blackstar's patented ISF (Infinite Shape Feature) control. The amplifier also includes studio-quality reverb, a power reduction switch, and various connectivity options for recording and external speakers.
3.1 Front View
Figure 1: Front view of the Blackstar HT20R MKII amplifier, showcasing the speaker grille and Blackstar logo.
3.2 Front Panel Controls
Figure 2: Top-down view of the amplifier's control panel, showing knobs for Clean, Overdrive, EQ, Reverb, and Master sections.
- Input: Connect your guitar here.
- Clean Channel: Volume, Voice switch (Classic/Modern), Tone.
- Overdrive Channel: Gain, Volume, Voice switch (Classic/Modern).
- OD Equalisation: Bass, Middle, Treble, ISF (Infinite Shape Feature).
- Reverb: Level control for the built-in reverb effect.
- Master: Master Volume control.
- 20W / 2W Switch: Reduces the amplifier's output power.
- Power Switch: Turns the amplifier on or off.
3.3 Rear Panel Connections
Figure 3: Rear view of the amplifier, displaying various input and output jacks and safety warnings.
- Mains Input: Connect the supplied power cord here.
- Speaker Outputs: Connect to external speaker cabinets (1x 16 Ohm, 1x 8 Ohm, 2x 16 Ohm).
- Emulated Output / MP3 / Line In: For direct recording or connecting external audio sources.
- Effects Loop: Send and Return jacks for connecting external effects pedals.
- Footswitch: Connect the supplied footswitch for channel and voice switching.
- USB Audio: For direct recording to a computer.
4. Setup
4.1 Unpacking and Placement
Carefully remove the amplifier from its packaging. Place the amplifier on a stable, level surface, ensuring adequate ventilation around the unit. Avoid placing it near heat sources or in direct sunlight.
4.2 Connecting Power
Ensure the amplifier's power switch is in the 'OFF' position. Connect the supplied mains power cable to the 'Mains Input' on the rear panel and then to a suitable wall outlet. Ensure the voltage matches your region's requirements.
4.3 Connecting Your Guitar
Connect your guitar to the 'Input' jack on the front panel using a high-quality instrument cable.
4.4 Connecting the Footswitch
The HT20R MKII comes with a two-button footswitch for convenient channel and voice switching.
Figure 4: The two-button footswitch for channel and voice selection.
Connect the footswitch to the 'Footswitch' jack on the rear panel. The 'CHANNEL' button switches between Clean and Overdrive channels. The 'VOICE' button switches between the two voices within the currently selected channel.
4.5 Connecting External Speakers (Optional)
If using an external speaker cabinet, ensure its impedance matches one of the available outputs (1x 16 Ohm, 1x 8 Ohm, or 2x 16 Ohm). Always connect a speaker cabinet before powering on the amplifier to prevent damage.
5. Operating Instructions
5.1 Powering On and Off
- Ensure all volume controls are set to minimum.
- Flip the 'Power' switch to the 'ON' position. The indicator light will illuminate.
- Allow a few moments for the tubes to warm up before playing.
- To power off, turn down all volume controls, then flip the 'Power' switch to 'OFF'.
5.2 Clean Channel Operation
Select the Clean channel using the front panel switch or footswitch. Adjust the 'Volume' knob for overall level. The 'Voice' switch offers two distinct clean tones: 'Classic' for a traditional, dynamic clean, and 'Modern' for a brighter, tighter clean. The 'Tone' knob provides a simple yet effective treble roll-off control.
5.3 Overdrive Channel Operation
Select the Overdrive channel. The 'Gain' knob controls the amount of distortion. The 'Volume' knob sets the output level for this channel. The 'Voice' switch provides 'Classic' for a rich, crunchy overdrive and 'Modern' for a more aggressive, high-gain tone.
5.4 OD Equalisation (EQ)
The Overdrive channel features a comprehensive EQ section:
- Bass: Adjusts the low-frequency content.
- Middle: Controls the mid-range frequencies, crucial for presence and cut.
- Treble: Adjusts the high-frequency content.
- ISF (Infinite Shape Feature): This patented control shifts the tone stack from a more American-style response (counter-clockwise) to a British-style response (clockwise), offering a wide spectrum of tonal characteristics.
5.5 Reverb and Master Volume
The 'Reverb' knob controls the level of the built-in digital reverb effect. The 'Master' knob controls the overall output volume of the amplifier.
5.6 Power Reduction Switch
The '20W / 2W' switch allows you to reduce the amplifier's output power from 20 watts to 2 watts, enabling you to achieve power tube saturation at lower volumes, ideal for practice or recording.
5.7 Emulated Output and USB Audio
The 'Emulated Output' provides a speaker-emulated signal for direct recording or connecting to a PA system. The 'USB Audio' connection allows you to record directly to your computer, offering both dry and emulated signals.
5.8 Effects Loop
The 'Effects Loop' (Send and Return) allows you to integrate external effects pedals into the amplifier's signal path, typically for time-based effects like delay and modulation, after the preamp section.
6. Maintenance
6.1 Cleaning
Disconnect the amplifier from the power supply before cleaning. Use a dry, soft cloth to wipe down the exterior. Do not use liquid cleaners or solvents, as they may damage the finish or internal components.
6.2 Tube Care
The HT20R MKII uses vacuum tubes, which have a finite lifespan. If you notice a decrease in performance, unusual noise, or a change in tone, the tubes may need replacement. This should be performed by a qualified technician.
7. Troubleshooting
- No Sound:
- Check power connection and ensure the amplifier is switched on.
- Verify guitar cable connections at both the guitar and amplifier.
- Ensure all volume controls (guitar, channel, master) are not at minimum.
- If using an external speaker, ensure it is correctly connected and functional.
- Poor Sound Quality / Excessive Noise:
- Check for faulty cables.
- Ensure proper grounding.
- Test with a different guitar.
- Tubes may be worn out and require replacement by a technician.
8. Specifications
| Feature | Specification |
|---|---|
| Output Wattage | 20 Watts (switchable to 2 Watts) |
| Speaker | 1x 12-inch |
| Channels | 2 (Clean, Overdrive) with 2 voices each |
| Reverb | Yes |
| Effects Loop | Yes |
| Emulated Output | Yes |
| USB Audio | Yes |
| Footswitch | Included (2-button) |
| Item Weight | 39.6 pounds |
| Material | Metal (chassis) |
| Connector Type | 6.35mm Jack |
| Power Source | Corded Electric |
8.1 Product Dimensions
Figure 5: Diagram showing the dimensions of the Blackstar HT20R MKII amplifier.
- Depth: 15.35 inches (39.0 cm)
- Width: 24.41 inches (62.0 cm)
- Height: 20.87 inches (53.0 cm)
9. Warranty and Support
For warranty information and technical support, please refer to the documentation included with your purchase or visit the official Blackstar Amplification website. Keep your proof of purchase for warranty claims.
