Used SPL Phonitor One D Headphone Monitoring Amplifier with 32-Bit DA Converter

When seeking unparalleled auditory fidelity, the Phonitor One D Headphone Monitoring Amplifier stands as a testament to high-quality, professional-grade audio equipment. This advanced amplifier is engineered to deliver an exceptional sound experience, featuring an innovative Phonitor Matrix and a state-of-the-art 32-bit DA-converter, ensuring precise and accurate sound reproduction for the most discerning audiophiles and audio professionals.

The heart of the Phonitor One D lies in its meticulously designed amplification stages. The preamplifier stage boasts two Burr-Brown OPA 2134 SoundPlus operational amplifiers, renowned for their audiophile-grade performance. These op-amps are characterized by their ultra-low noise and minimal distortion levels, a mere 0.00008%, which translates to a pristine audio signal. The true FET input stage of the OPA 2134, with its impressive 20V/s slew rate, contributes to the dynamic and lively playback that professionals demand.

In the signal path, low capacitance film capacitors serve as bypass capacitors, ensuring a more accurate transmission of high-frequency components. Coupling capacitors from Panasonic, featuring 'Electric Double Layer' gold electrolytic technology, provide the highest storage capacity, further enhancing the sound quality.

The power amplifier section is a testament to innovative engineering, operating in class AB mode as a push-pull amplifier. This design allows for a higher gain and output voltage, delivering a robust and stable sound image. The output stage transistors are thermally coupled, ensuring consistency in performance. A buffer circuit with low source resistance in the power supply ensures ample current reserves for driving even low-impedance headphones with ease.

The revolutionary Phonitor Matrix, with its adjustable crossfeed, is a game-changer for headphone mixing, allowing for the creation of mixes that translate seamlessly to speaker systems. It features three parameters: Crossfeed, Speaker Angle, and Center Level, with the latter two preset to the most commonly used values (-1 dB and 30 degrees, respectively). The crossfeed's intensity is fully variable and can be engaged via a relay for a clean signal path when not in use.

Connectivity is versatile with three stereo inputs: two analog and one digital USB input. The Phonitor One D seamlessly integrates with computers, tablets, phones, CD players, mixers, synthesizers, and analog tape machines, offering both balanced (TRS) and unbalanced (RCA) connections.

The premium AK4490 converter chip lies at the core of the 32-bit DA-converter, featuring AKM's Velvet Sound technology. This chip supports ultra-high sampling frequencies up to 768kHz PCM and DSD playback up to DSD256, qualifying the Phonitor One D for the highest resolution audio playback. The USB connection is Class Compliant, ensuring full performance bandwidth without the need for driver installation on Mac and iOS devices.

An unaltered line out allows the Phonitor One D to be looped between devices without losing an output connection, making it ideal for multiple listeners or for routing the signal to a mixer or recording device. This flexibility also positions the Phonitor One D as a cutting-edge DA-converter for a variety of audio applications.

The power supply is the foundation of good sound, and the Phonitor One D's internal secondary power supply generates a professional-level voltage of +/-17 Volts, capable of achieving up to +22.5 dB. An advanced low-drop voltage regulation ensures consistent performance even at maximum operation voltage. The included 1.5 A power supply unit ensures that the Phonitor One D delivers its full power potential, making it an essential tool for those who demand professional, high-quality sound in their audio monitoring and mixing endeavors.