Overview of SPL Phonitor One D Headphone Monitoring Amplifier with 32-bit DA-converter
Two Burr-Brown OPA 2134 SoundPlusTM 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.
The Power Amplifier
Two Burr-Brown OPA 2134 SoundPlusTM 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.
The output stage of the headphone amplifier is designed as a push-pull amplifier in class AB mode. The output stage transistors are thermally coupled and thus run particularly coherently, which contributes to a consistent and stable sound image.
The power supply has a buffer circuit with low source resistance, ensuring generous current reserves even when
operating low-impedance headphones.
Three Stereo Inputs
Two analog stereo sources and one digital source can be connected to Phonitor One d. The computer, tablet or phone
are preferably connected via USB. Other players such as a CD player, mixer, synthesizer or an analog tape machine / tape deck can be connected to the analog line inputs either balanced (TRS jacks) or unbalanced (RCA).
32- Bit D/A Converter
The converter chip used is the Premium AK4490, a new generation of premium 32-bit DACs equipped with AKM’s
Velvet Sound®. This technology makes the finest details audible thanks to its low-distortion architecture.
It supports sampling frequencies up to 768kHz PCM (16x CD resolution) and DSD (Direct Stream Digital) playback up to
DSD4 or DSD256 (11.2 MHz) resolution. This qualifies the Phonitor One d for the currently highest resolution audio playback.
The USB connection is Class Compliant. This means that all Mac computers and iOS devices like iPads and iPhones can use the full performance bandwidth of the DA-converter without driver installation. iOS devices require the camera adapter. For Windows a driver is required.
The Revolution
The revolution in the headphone amplifier is the Phonitor Matrix – mixes made on headphones sound as they were mixed on speakers. The Phonitor Matrix in its largest expansion stage has three setting parameters: Crossfeed, Speaker Angle and Center Level.
In the Phonitor One, the center level is preset to -1 dB and the speaker angle to 30°. These are the most commonly used values. The crossfeed function determines the crosstalk of the channels, the so-called interaural level difference. The intensity of the crossfeed is fully variable. When the Crossfeed control is in the OFF-position the Phonitor Matrix is switched off – it is removed out off the audio signal path via relay (hysteresis circuit).
Music City Canada is an authorized reseller for SPL products. Purchases are backed with full manufacturer warranty in Canada. All orders ship from our Canadian warehouse.
