True to the motto Number One In Sound, SPL has developed a new product line that combines the sound of their big devices with a desktop-friendly design and an affordable price for the ambitious user. The first two Series One devices, Phonitor Oneand Phonitor One d–both headphone amplifiers, will be launched on October 05, 2020. More devices will follow soon.
The SPL headphone amplifier Phonitor One allows high-quality monitoring of analog sources. Thanks to the Phonitor Matrix with Crossfeed control, you can create mixes that sound as if they were mixed on speakers. An analog volume controller, an aluminum front panel and a high-end metal housing show that no compromises have been made in terms of quality. The Phonitor One d also features an internal DA converter with top specifications. PCM signals up to 768 kHz/32Bit and Direct Stream Digital up to DSD4 playback leave nothing to be desired. A balanced stereo line output predestines the Phonitor One d to use it as a stand-alone DAC.

” I am excited that with the Series One we have developed a new product line for the ambitious sound creator. It was a challenge to bring the famous SPL sound to this series –I'm really proud of the result –it's something you can hear and see.“ Jens Gronwald, Developer

The Design Of The Amplification Stages

The Preamplifier Stage
Two Burr-Brown OPA 2134 SoundPlus™ operational amplifiers provide the pre-amplification. These are specially designed for audiophile circuits and are characterized by extremely low noise and minimal distortion of only 0.00008%.

Thanks to a true FET stage, the OPA 2134 achieves a slew rate of 20V/μs, making it a high-speed operational amplifier. This has an immediate positive effect on the liveliness of the playback.

In addition, low capacitance film capacitors are installed in the signal path as bypass capacitors of the coupling capacitors, which ensures a more precise transmission of the high-frequency signal components.

The excellent Panasonic ‘Electric Double Layer’ gold electrolytic capacitors are used as coupling capacitors. They offer the highest storage capacity of all capacitor technologies.

Analog inputs; 6.35 mm (1/4") TRS Jack (balanced), RCA
  • Input gain (max.)-+22.5dBu
  • Input impedance Line In 2 (balanced)-20kΩ
  • Common mode rejection-< 60dB
  • Input impedance Line In 1 (unbalanced)-47kΩ
Headphones Output; 6.35 mm (1/4") TRS Jack
  • Wiring-Tip = Left, Ring = Right, Sleeve = GND
  • Source impedance-20Ω
  • Frequency range (-3 dB)-10 Hz -200kHz
  • Noise (A-weighted, 600 Ω)--97dBu
  • THD + N (0 dBu, 10 Hz –22 kHz, 600 Ω)-0,002%
  • THD + N (0 dBu, 10 Hz –22 kHz, 32 Ω)-0,013%
  • Max output power (600 Ω)-2 x 190mW
  • Max output power (250 Ω)-2 x 330mW
  • Max output power (47 Ω)-2 x 400mW
  • Fade-out attenuation (600 Ω)--99dB
  • Crosstalk (1 kHz, 600 Ω)--75dB
Internal Power Supply
  • Operating voltage for analog audio-+/-17V
  • Operating voltage for headphone amplifier-+/-19V
  • Operating voltage for relays-+12V
External Power Supply
  • AC/DC switching adaptor-Mean Well GE18/12-SC
  • DC plug-(+) pin 2.1mm; (-) outside ring 5.5mm
  • Input-100 -240 V AC; 50 -60 Hz; 0.7A
  • Output-12 V DC; 1.5A

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