SPL Phonitor One D Audiophile Headphone Amplifier

Headphone Amplifier and DAC

SPL’s Phonitor One D model is a headphone amplifier and DAC featuring a pristine AK4490 conversion chip and built in Phonitor Matrix technology for even more translatable mixes.

Part No:
Usually Ships in 1-2 Days
£599.00 £499.17
Did you find this item priced lower than £499.17 somewhere else? Yes

SPL’s Phonitor One D model is a headphone amplifier and DAC featuring a pristine AK4490 conversion chip and built in Phonitor Matrix technology for even more translatable mixes.

SoundPlus From Burr-Brown
The Phonitor One D’s preamp stage is powered by two OPA2134 operational amplifiers from electronics artisans Burr-Brown. The op amps are specially designed for audiophile circuits and as such feature a minimal distortion value of just 0.00008%.

Thanks to the Phonitor One D’s true FET design, the OPA2134 achieves an overall slew of 20V/µs which rewards the converter's liveliness during playback.

Class A/B Output Stage
The output stage of the Phonitor One D is meticulously designed with thermally coupled transistors, a PSU buffer circuit featuring low source resistance, and capable of providing generous current reserves even when running low impedance headphones.

Versatile I/O Array
Phonitor One D allows for connectivity to a wide range of sources and peripherals. On the rear of the unit are two analogue stereo inputs for devices such as CD players, mixers, synthesisers or tape machines; alongside a digital source input perfect for connecting a PC, Mac, tablet or smartphone.

32-Bit PCM & DSD Conversion
Built around the Premium AK4490 conversion chip, the Phonitor One D makes the even the finest details audible thanks to low distortion architecture, 32-bit encoding and AKM’s revered Velvet Sound technology.

Sampling frequencies of up to 768kHz for PCM and up to 11.2MHz via DSD4 or DSD256 making the Phonitor One D a high hitter for pure audio playback resolution.

USB connectivity is class compliant meaning that additional driver downloads are not necessary for Mac or iOS devices, and the only additional accessory required for iPad or iPhone connectivity is a USB Camera to lightning adaptor.

Phonitor Matrix
Preset to a -1dB centre level and 30º speaker angle emulation, the Phonitor One D’s built-in Phonitor Matrix feature allows mixing on headphones as if the user were listening to two studio near fields in a mixing suite. SPL achieve this feat by building in an intelligent crosstalk technology to emulate the effect of angled speakers rather than the hard-left hard-right performance that headphones usually exhibit.

In practice the use of Phonitor Matrix, which can be easily adjusted by the Crossfeed control on the front of the Phonitor One D’s front panel, provides an environment to achieve far greater translatable mixes when switching between headphones and studio monitors on the fly.

  • Audiophile Headphone Amplifier
  • Innovative Phonitor Matrix
  • 32-bit DA-converter
  • Burr-Brown opamps
  • Class AB output stage
  • Outstanding sound quality
More Information


  • Max Input: +22.5 dBu
  • Input Impedance: 20 kΩ (line 2)
  • CMR: < 60 dB
  • Max Output: +22 dBu
  • Output Impedance: 150 Ω (speaker)
  • Frequency Range: 10 Hz - 200 kHz (-3dB)
  • Noise: - 99 dB (A-weighted, 0 dBu, 600 Ω load)
  • THD: 0.002% (0 dBu, 10 Hz – 22 kHz, 600 Ω)
  • Crosstalk: < 75 dB (1 kHz)
  • Dynamic Range: 121.5 dB
  • Sample Rates: 44.48 – 768 kHz (PCM/USB)


  • Operating Voltage: +/- 17 V (analogue), +/- 19 V (head amp)
  • Switching Adaptor: Mean Well GE18/12-SC
  • DC Plug: (+) pin 2.1mm; (-) outside ring 5.5mm
  • Input: 100 - 240 V AC; 50 - 60 Hz; 0.7 A
  • Output: 12 V DC; 1.5 A

Physical Properties

  • Dimensions: 210 x 49.6 x 220 mm (WxHxD)
  • Weight: 1.45 kg
  • Shipping Weight: 2 kg