Headphone Amplifiers

The ampsandsound Bigger Ben Rev 3 is a hybrid headphone and loudspeaker amplifier using single-ended Class A, zero-feedback tube topology with cathode/automatic bias and user- replaceable 6L6GC-, EL34-, KT66-, KT77-, KT88-, 6550-, or KT90-type output tubes. It uses input transformers, Jupiter copper-foil-in-wax coupling capacitors, custom-wound output transformers, and dedicated 8-, 16-, 32-, 100-, and 300-ohm headphone taps; the unit is available with either XLR or RCA input and includes XLR outputs. With KT88 output tubes, it is rated at 8 W RMS into 8 ohms and 5 W RMS into 32 or 300 ohms at 1 kHz, with listed noise levels of 300 µV RMS on the 8-ohm tap, 340 µV RMS on the 32-ohm tap, and 480 µV RMS on the 300-ohm tap.

The Audeze LCD-24 is a flagship headphone incorporating a staggered Fluxor™ magnetic structure and nano-scale diaphragms. Its stated sound profile features a vibrant midrange, powerful bass, and extended treble. The made-to-order model is priced at $3,500, including a hard travel case and premium silver-plated copper LCD series cable.

The Audeze LCD-5s is a flagship over-ear, open-back planar magnetic headphone using a 90 mm Nano-Scale Parallel Uniforce™ diaphragm, Fluxor™ magnet array, Fazor™ phase management, and SLAM™ acoustic management. Its construction combines carbon fiber, magnesium, genuine leather, and polished polymer acetate, with redesigned earpads and a directional OCC high-purity copper cable. Specifications include 35-ohm impedance, 5 Hz–50 kHz frequency response, <0.1% THD at 100 dB SPL, 90 dB/1 mW sensitivity, and a 475 g weight.

The King MKII is a two-stage hybrid headphone amplifier designed for Audeze and matched particularly with the LCD-4. Its topology uses a pair of twin-triode E88CC input tubes, a differential P-MOSFET driver, and NPN MOSFET output devices, with separate left/right PCBs, individual voltage regulators, a DC servo, and a symmetrical ±16 V regulated power supply. It provides 6 W of music power with low impedance, low distortion, and wide frequency response; the product is a legacy model no longer available for sale.

The Nirvana is Auris Audio's full-sized, single-ended Class-A tube headphone amplifier, built around iconic EL34 power tubes paired with an ECC82 driver tube and fed by a dedicated external power supply for constant DC power delivery ([HeadAmp official listing](https://www.headamp.com/products/auris-nirvana), [Headfonia review](https://www.aurisaudio.shop/blogs/reviews/nirvana-review-by-headfonia)). It is rated at 6.5W of pure Class-A power per channel, features backlit VU meters and a selectable output-impedance system spanning 32 to 600 Ohms to match a wide range of dynamic and planar magnetic headphones, and has since been updated through several generations (Nirvana IV, Nirvana 6) ([HeadAmp official listing](https://www.headamp.com/products/auris-nirvana), [Bloom Audio Nirvana 6 listing](https://www.aurisaudio.shop/products/nirvana-6)).

The Ayre Codex is a digital-to-analog converter, headphone amplifier, and digital preamplifier that can operate as a standalone component or within a larger system. Its analog circuitry uses a fully balanced signal path throughout and a zero-feedback design. It is categorized as digital equipment.

The Ayre QX-5 Twenty USB2 is a field-installable USB digital-input circuit-board upgrade for the QX-5 Twenty digital audio component. It uses a redesigned voltage-regulation scheme and improved signal isolation, supporting PCM at 16-, 20-, and 24-bit resolution up to 768 kHz, along with DSD64, DSD128, DSD256, and DSD512. The kit includes the USB2 circuit board, firmware thumb drive, installation hardware, and instructions.

The HPA-01M is a portable battery-powered headphone amplifier from Bakoon Products, using the brand's proprietary "SATRI" current-drive circuit — a design that drives headphones via current rather than the voltage-drive method used by most conventional amplifiers ([Headfonics review](https://headfonics.com/the-hpa-01m-portable-amp-by-bakoon/), [kopfhoererboutique product listing](https://kopfhoererboutique.com/products/bakoon-hpa-01m)). It is a scaled-down, portable version of the desktop HPA-01, packing dual 8.4V Li-Ion batteries into a compact chassis about the size of a large smartphone, with simultaneous current- and voltage-drive 3.5mm outputs and a switchable high/low gain setting ([Headfonics review](https://headfonics.com/the-hpa-01m-portable-amp-by-bakoon/), [Headfonics review, page 2](https://headfonics.com/the-hpa-01m-portable-amp-by-bakoon/2/)).

The Benchmark HPA4 is a solid-state, dual-mono reference headphone/line amplifier built around Benchmark's own THX-AAA-888 feed-forward error-correction modules, combining the company's LA4 line amplifier with a high-current headphone stage. It functions equally as a low-distortion headphone amp and as a full-featured analog preamplifier.

The Benchmark HPA4 is a solid-state, dual-mono reference headphone/line amplifier built around Benchmark's own THX-AAA-888 feed-forward error-correction modules, combining the company's LA4 line amplifier with a high-current headphone stage. It functions equally as a low-distortion headphone amp and as a full-featured analog preamplifier.

The Soloist 3X GT is Burson Audio's flagship dual-mono, pure Class-A desktop headphone amplifier and line-stage preamplifier, built around fully discrete V6 Vivid op-amps and dual MUSES72320 volume-control chips instead of off-the-shelf op-amp chips. It is designed as a fully differential, XLR-balanced signal path with two symmetrical mono amplifier sections, delivering up to 10W per channel into low-impedance loads for driving power-hungry planar-magnetic and electrostatic-adjacent headphones.

Compact vacuum tube headphone amplifier with EL84 output tubes and 12AU7/12AX7 input stage, offering selectable impedance modes for 8-600 ohm headphones plus a preamp output.

The HA-300 MK2 is Cayin's flagship transformer-coupled, single-ended triode (SET/SETA) tube amplifier, successor to the original HA-300, built as a two-chassis design with a separate power supply driven by a quad of NOS RCA 22DE4 rectifier tubes ([Headfonics review](https://headfonics.com/cayin-ha-300mk2-review/), [starspickeraudio.net](https://starspickeraudio.net/blogs/blog/cayin-ha-300-mk2-irresistible-sound)). It uses matched Gold Lion Genalex PX300B output tubes and Tung-Sol 6SN7GTB driver tubes to deliver both headphone amplification (up to 6W at 4-pin XLR) and true Class-A SET speaker amplification (8W per channel), with a 3-stage impedance selector to optimally match a wide range of headphones ([Cayin official product page](https://en.cayin.cn/features/7/59/574.html), [Cayin official manual PDF](https://cayin.com/ca-inhalte/uploads/2025/10/HA-300MK2-English-Manual-20220412.pdf)).

The HA-6A is Cayin's transformer-coupled vacuum-tube desktop headphone amplifier, supporting swappable EL34 and KT88 output tubes in both Triode (TR) and Ultra-Linear (UL) operating modes for adjustable tonal character and power. It offers fully balanced 4-pin XLR and 4.4mm Pentaconn outputs alongside a single-ended 6.35mm jack, with three-position gain/impedance matching for headphones from 8Ω to 600Ω.

The dCS Bartók is a network-attached DAC and headphone amplifier that brought dCS's flagship Ring DAC™ topology, previously reserved for the multi-box Vivaldi system, into a single-chassis "entry-level" model for the British manufacturer. It combines an asynchronous USB, dual AES/EBU, S/PDIF and network streaming inputs with an optional Class A headphone stage, and has since been upgraded through "2.0" and "APEX" hardware revisions that add improved mapping, DSD128 upsampling, and refined analog output stages.

The Stratus is a purist, single-ended 2A3 triode headphone amplifier hand-built point-to-point by Donald North Audio (DNA Audio), a small US direct-order manufacturer with a long-running, dedicated following in the Head-Fi and headphones.com enthusiast communities.

The HPA-23RM is a pocketable, battery-powered reference headphone amplifier from Enleum, the South Korea-based successor brand to the cult favorite Bakoon Products, continuing Bakoon's proprietary current-drive amplification legacy in a limited first production run.

Erzetich Scylla is a fully balanced, dual-mono Class A headphone amplifier for premium headphones. It supports headphone impedances from 8–600 ohms and has a frequency response of 4 Hz–40 kHz at −1 dB. The amplifier consumes 25 W and measures 510 × 140 × 330 mm (W × H × D), with a weight of 9,300 g.

The Arioso 300B is a single-ended Class A tube amplifier made by Feliks Audio. It uses two 300B output tubes, two 6N8S tubes, and one 5C3S tube, with a handcrafted construction using selected high-end components. The amplifier provides 2 × 8 W output, 4- and 8-ohm speaker outputs, three RCA inputs, 15 Hz–32 kHz frequency response (±3 dB), 0.3% THD at 1 W and 2.5% THD at 8 W, and 140 VA power consumption.

Feliks Audio Bliss is a fully balanced electrostatic headphone amplifier using four 6E5P driver tubes, four 300B power tubes, and four EL34 tubes in a pure Class A, fully differential Hedge topology without output transformers. It provides adjustable bias from 120–360 V through the 6-pin Normal socket and 240–720 V through the 5-pin Pro socket, with a maximum output of 520 V RMS (1,470 V peak-to-peak), 2 V/4 V input sensitivity, approximately 250× gain, and RCA and balanced XLR inputs. The amplifier has a point-to-point-wired construction, Lundahl and Toroidy transformers, a 24-position DACT stepped attenuator, and solid-wood finishes in Oak, American Walnut, or Zebrano.

The Echo Classic is a hand-crafted tube amplifier manufactured by Feliks Audio. It has a 350 mW power output, 20 dB amplification level, 15 Hz–45 kHz frequency response (±3 dB), 0.4% THD at 300 ohms and 20 mW, and an optimal headphone impedance range of 80–600 ohms. It uses a 6.3 mm headphone jack and includes one pair each of driver and power tubes.

The ECHO VIBE is a tube amplifier made by Feliks Audio. It has a 100 kΩ impedance, 15 Hz–45 kHz frequency response (±3 dB), 350 mW power output, 20 dB amplification level, and 0.4% THD at 300 Ω and 20 mW. It includes a 6.3 mm headphone output, supports headphones rated at 80–600 Ω, and features an engraved wood enclosure with one pair each of driver and power tubes.

Feliks Audio ELISE is a tube headphone amplifier with a hand-crafted chassis and a 6.3 mm headphone output. It uses a matched pair of PsVane 6SN7 Hi-Fi driver tubes and a matched pair of NOS 6N13S power tubes. Specifications include 200 mW power output, 20 dB amplification, 0.4% THD at 300 ohms and 20 mW, 10 Hz–60 kHz frequency response ±3 dB at 300 ohms, 100 kΩ impedance, and compatibility with headphones rated from 32 to 600 ohms.