The Single 25 is a Single-Ended amplifier, using a KT150 tube—a first in the world of electric guitar amplifiers.
It offers a wide range of tones, from scooped American cleans to thick, saturated overdrive, all while maintaining exceptional warmth, dynamics, and clarity.
Features:
25W Single-Ended Amplifier, Pure Class A, all tube guitar combo
Proprietary Reconfigurable Auto Bias System for True Power Control (25W / 10W / 4W)
Tone Controls (Bass / Mid / Treble)
Bright Switch
Tube Driven Spring Reverb (Depth / Mix)
Boost (+8dB) / Lead Channel
Footswitch (Reverb / Boost), 3.5m Cable
12” Speaker, Eminence Legend 1258
Solid Pine Cabinet, Made in Germany
Dustcover, Made in Germany, with embroidery logo
Current Lead Time: 3 Months, Finish customizable—see Pre-Order.
€3190
AN IRON fist in a velvet glove
I have always admired the sound of single-ended amplifiers like the Fender Champ. In contrast to push-pull amplifiers (with two or more power tubes), which only operate in Class A for the initial watts, single-ended amplifiers perform in Class A across the entire power range. This results in an incredibly dynamic, warm sound, often described as an "iron fist in a velvet glove." However, single-ended guitar amplifiers have rarely exceeded 12W. Until now.
The Single 25 is the first guitar amplifier to use a KT150 tube, delivering 25W of pure Class A. It blends the shimmering clarity of single-ended designs with the authority and bass response of larger, more powerful push-pull amps. Paired with a warm breakup, it creates harmonically complex overdriven sounds.
Innovative power control
Designed for ultimate versatility, the Single 25 offers three power settings—25W, 10W, and 4W—via a dedicated power knob. This makes it adaptable for any setting, from quiet bedroom practice to studio sessions and live performances. Thanks to its proprietary, -entirely analog- reconfigurable autobias system, the amp adjusts its internal parameters to truly modify output power, ensuring tonal consistency at every level. Tube replacement is effortless, with the system automatically calibrating bias for optimal performance. Curious to know more about the system ? Find out more here.
improved Tone stack
The preamplification section uses two 12AX7 tubes, resulting in a signal path reduced to the essentials. Initially inspired by Blackface-era circuits, the tone stack has been modernized to offer a more precise and gradual control over the bass, mid, and treble frequencies. You'll truly be able to tailor your sound, dialing in exactly the tone you want.
LOW NOISE - STUDIO GRADE
A proprietary high-voltage regulated power supply ensures tight bass and exceptional clarity. Additionally, it enables ultra-low noise, making the Single 25 ideal for recording. The amp’s robust 2mm PCB, built with double the industry-standard copper thickness, ensures both durability and superior signal integrity. Carefully designed ground planes and power regulation result in noise levels well below those of competing amplifiers.
vibration control for superior sound
As you may have experienced, combo amplifiers often suffer from unwanted tube rattle and vibrations, which can degrade tone and reliability. The Single 25 solves this using advanced mechanical isolation. The entire PCB and tubes are mounted on custom silicone dampers, reducing vibrations to enhance clarity and durability. Curious to see how it performs? You can find comparative measurements made during development here.
Compact and Lightweight
The Single 25 delivers impressive power in a portable design. Custom toroidal transformers and an aluminum chassis ensure lightweight durability, while the solid pine enclosure reduces weight and enhances tonal richness with a fuller, more lively sound.
built to last
The Single 25 is a first-class professional guitar amplifier designed with reliability at its core. In that sense, it comes with an industry-leading 10-year warranty.
Accessories
Each Single 25 is delivered with a durable footswitch and a padded dustcover, ensuring safe and hassle-free transport.
Features
· All tube guitar combo
· Power: 4 / 10 / 25W into 8 ohms
· Speaker Output: 1/4” Jack (additional speaker output on request)
· Tone Controls: Bass, Mid, Treble
· Spring Reverb (Footswitchable): Depth, Mix
The Single 25 embodies a tube-driven spring reverb with adjustable depth and intensity, allowing for subtle reverb to deep, bouncing sounds.
· Boost (Footswitchable) : +8dB / Lead channel
The boost delivers a thicker, rawer sound with just enough extra gain to seamlessly switch to leads while playing guitar.
· Bright Switch
· Solid Pine Cabinet
· Loudspeaker : 12” Eminence 1258
· Line output (160 Ohms)
Specifications
· Tubes :
o Power Tube : KT150 Tung-Sol
o Preamp Tubes :
V1: ECC83 NOS
V2: ECC83-WB Tube Amp Doctor
o Reverb Tube: ECC81 - 12AT7 JJ
· Weight: 17.5 Kg
· Dimensions: 9.5″ (24.13 cm) x 19.875″ (50.5 cm) x 16″ (40.6 cm)
· Fuses:
o Main : 1A Slow Blow (220-240VAC Version) / 2A Slow Blow (110-120VAC Version)
o Secondary : 50mA Fast Blow
· Main Voltage: 220-240VAC / 50Hz or 110-120VAC / 60Hz
· Power Consumption: 100W