Apos Gremlin Headphone Amp,Headphone Tube Amplifier,Class A Balanced Tube Amp,Replaceable Tubes 12au7,6922/XLR,4.4mm Balanced Interface.Amp for HiFi Desktop Speakers,Loved by Audio Enthusiasts

Class A and fully-balanced at an unheard of price

The Gremlin tube headphone amp is a little monster with a ferocious bite. With 1250mW of output power, it has the muscle to drive most headphones that cross its path. It may be ugly, naked, and small, but don’t judge a beast by its cover. For a killer price, you’re getting a Class A, fully-balanced tube amp with matched tubes—something unheard of for the cost. It delivers sound that’s sumptuous and lush, with musical tonality and heart-melting mids. Once it gets its claws in you, you won’t want it to let go.

Feeding the beast: Tubes + transistors

The Gremlin is a hybrid headphone amp that combines the precision of transistors with the warmth of vacuum tubes. While solid-state amps (which rely solely on transistors) deliver accuracy, they lack the soul of tubes. In the Gremlin, the vacuum tubes in the pre-amp stage flood your music with rich harmonics and a warmth that solid-state amps can’t touch.

Always hungry: the Gremlin’s Class A appetite

The Gremlin is a predator that never rests. With a Class A design, it’s always on the hunt, keeping the current flowing without pause. Other amps flip their transistors on and off to save energy and keep cool—efficient, sure, but prone to distortion that muddles the sound. Not this beast. Its relentless operation means every note is delivered with the raw purity and ferocious detail that only Class A amplification can provide.

A poised predator: a fully-balanced amplifier

With a fully-balanced design from input to output, the Gremlin cancels out the kind of hums, buzzes, and interference that can creep in with unbalanced systems. This means you get a cleaner sound—especially important if you’re using sensitive headphones or high-end equipment that picks up every little detail. The Gremlin gives you the best of both worlds: the warm, rich tones of tube amplification with the minimal interference of balanced design.

Matched Ray Tubes: the Gremlin’s natural weapon

The Gremlin comes armed with a matched pair of CORE 12AU7 from Ray Tubes to give you that signature tube warmth right out of the box. When tubes are matched, it means they’ve been carefully tested to ensure they work together as a pair, delivering the same output and frequency response. This results in better soundstage, clarity, and stereo imaging—key elements for an hi-fi listening experience. And if you’re looking for even more depth and detail, we recommend upgrading to a pair of matched Ray Tubes SELECT 12AU7 tubes. Choose the 12AU7 SELECT and you’ll get both sets—letting you tube roll and discover the extent of the Gremlin’s power.

Embark on the quest for your perfect sound

The Gremlin Amp is made for audio lovers who want to explore the world of sound. It works with any 12AU7 or 6922 tubes, new or old, allowing you to easily swap and try new types. Whether you prefer a lush or linear sound, the Gremlin lets you customize your audio setup whenever you want a change.

Product Highlights

Class A headphone amp with 1250mW of output power at 32Ω

Fully-balanced architecture with 4-pin XLR and 4.4mm inputs and outputs

Low noise floor: 100dB SN

Excellent channel separation: 104dB at 1kHz

Wide headphone compatibility: suitable for headphones with an impedance range of 8-600Ω.

Comes with matched pair of Ray Tubes CORE 12AU7

Specs
Uses 12AU7 or 6922 tubes

Three-level tube with Class A buffer output

Inputs: XLR, 4.4mm

Outputs: 4-pin XLR balanced headphone jack, 4.4mm balanced headphone jack

Uses a DC 18-24V power supply

Output power: 1250mW @ 32Ω

Frequency response: 20Hz-50KHz (+/-0.5dB)

Signal to noise ratio: 110dB

Minimum distortion: 0.01% (1KHz)

Separation degree: 104dB (1KHz)

Suitable headphones: 8-600Ω

Dimensions: 5″ W, 3 1/4″ D, 2 1/2″ H

FAQ:

Is this a speaker/guitar amp?
— The Gremlin is a headphone amp only. It is not a speaker or guitar amp

Can it be used as pre-amp?
— No

Is it balanced only? What does that mean?
— The Gremlin requires 2 XLR or 4.4mm input/outputs. You can try Apos Flow XLR Cables

What DAC can I pair it with?
— Any DAC with Balanced XLR or 4.4mm outputs

How do I roll/swap tubes?
— Please see GIF in product images

Can I use 6922 tubes?
— Yes, please refer to the manual and GIF in product images for tube selection

Can I switch on and off the LED under the Gremlin?
— Yes

Can I switch off the orange LEDs under tubes?
— No

• Class A and fully-balanced at an unheard of price The Gremlin Class A Tube Headphone Amplifier is a little monster with a ferocious bite. With 1250mW of output power, it has the muscle to drive most headphones that cross its path. It may be ugly, naked, and small, but don't judge a beast by its cover. For just $135, you're getting a Class A, fully-balanced headphone tube amplifier with matched tubes—something unheard of at this price. It delivers sound that’s sumptuous and lush, with musical tonality and heart-melting mids. Once it gets its claws in you, you won't want it to let go.
• Feeding the beast: Tubes + transistors The Gremlin is a hybrid headphone amp that combines the precision of transistors with the warmth of vacuum tubes. While solid-state amps (which rely solely on transistors) deliver accuracy, they lack the soul of tubes. In the Gremlin, the vacuum tubes in the pre-amp stage flood your music with rich harmonics and a warmth that solid-state amps can’t touch.
• A poised predator: a fully-balanced amplifier With a fully-balanced design featuring balanced XLR inputs and balanced 4-pin XLR / balanced 4.4mm outputs, the Gremlin cancels out the kind of hums, buzzes, and interference that can creep in with unbalanced systems. This means you get a cleaner sound—especially important if you're using sensitive headphones or high-end equipment that picks up every little detail. The Gremlin gives you the best of both worlds: the warm, rich tones of tube amplification with the minimal interference of balanced design.
• Matched Ray Tubes: the Gremlin’s natural weapon The Gremlin comes armed with a matched pair of CORE 12AU7 tubes from Ray Tubes to give you that signature tube warmth right out of the box. When tubes are matched, it means they’ve been carefully tested to ensure they work together as a pair, delivering the same output and frequency response. This results in better soundstage, clarity, and stereo imaging—key elements for an hi-fi listening experience.
• Embark on the quest for your perfect sound The Gremlin Amp is made for audio lovers who want to explore the world of sound. It works with any 12AU7 or 6922 tubes, new or old, allowing you to easily swap and try new types. Whether you prefer a lush or linear sound, the Gremlin lets you customize your audio setup whenever you want a change.