Up to five stereo sources can be connected to the Phonitor x: XLR, RCA, and via the optional DAC768xs, USB, COAX, and OPTICAL.The Phonitor x accepts a variety of different audio connections.Balanced via XLR or unbalanced via RCA jacks.With the optional DAC768xs, three additional digital sources can be added. PCM audio is received in S/P-DIF format both coaxially (RCA) and optically (Toslink F06).Both PCM audio and DSD audio can be converted via USB.The DAC automatically picks up the sampling rate and resolution of the digital playback source. No matter if a streamer, computer or CD player is connected. No further settings on the Phonitor x are necessary.The DAC768xsThe converter chip in the optional digital-to-analog converter is the highly acclaimed AKM AK4490 Velvet Sound premium DAC chip, which thanks to its architecture reproduces the finest sound details.It converts PCM audio at 32-bit resolution and a sampling rate of up to 768 kHz, which is 16 times the resolution of a CD. Direct Stream Digital is also supported up to a resolution of DSD4 or DSD256.Unlike the DAC768, which is built into the Director Mk2 for example or available as an option for the Phonitor xe, the DAC768xs does not offer an AES/EBU digital input. The SPL DLP120 with VOLTAiR technology was also not included in the DAC768xs. Nevertheless, it offers a great performance that is unparalleled in this league.Good ol’ timesTwo mechanical VU meters visualize the input levels for the left and right audio channel.Finding the middleis not always easy. By our very nature, hearing can be leaning more to the left or more to the right. This is especially obvious when listening with headphones.That’s why Phonitor x has the uniquely finely resolved laterality control. With it, the center can be found perfectly.With the mode switch you can choose between stereo or mono playback. To the right, the laterality control is switched on.The Revolution: Phonitor-MatrixThe Phonitor Matrix is the revolution in the headphone amplifier.Thanks to the Phonitor Matrix, music can be experienced on headphones as if it was played on speakers. The tiring super stereo effect is a thing of the past.Enjoy their music without listening fatigue and exactly the way it should be heard. Music is normally produced and mixed for playback on stereo speakers.Listening on headphones is different from listening on loudspeakers. The biggest difference is the lack of crossing signals of the sound signal from the left speaker to the right ear and from the right speaker to the left ear. These crossing signals are missing in conventional headphone listening, because there are no signals crossing from one side of the headphones to the other.This results in an unnaturally wide stereo image and the various sound sources of the audio signal are not localized as the sound engineer intended them to. This effect is often referred to as “super stereo effect”. During conventional listening on headphones, our brain can balance the false representation of the playback to a certain extent – but this is very exhausting.The SPL Phonitor Matrix can correct this false stereo image with an analog circuitry. The Phonitor Matrix therefore not only ensures a correct representation of the stereo image, but also a relaxed listening experience.Sounds goodWith all devices of the Professional Fidelity series we develop not only according to plan, but also by ear. Many important components are installed on the circuit boards using Through-hole technology. This way we can ensure that we can use the best sounding components.The VOLTAiR TechnologyThe 120V technology is our reference technology. The 120V technology is unique in the world. It operates at a DC voltage of 120 volts. This is four times that of IC-based semiconductor op-amps. In our Professional Fidelity series, we refer to this unsurpassed technology as VOLTAiR technology.The highest possible audio quality requires the highest possible audio operating voltage.The 120V technology works with +/-60 V. To be able to handle such a high voltage, we have developed special proprietary operational amplifiers that can operate with a DC voltage of +/-60 V: the SPL 120V SUPRA operational amplifiers. This high voltage would destroy conventional components and operational amplifiers.By the way, the “120V” in the name of the technology has nothing to do with the local mains voltage from the mains power socket. This is about the operating voltage inside the device with which the audio signals are processed.The mains voltage from the mains power socket is transformed to the required secondary voltage in the device’s internal linear power supply with toroidal transformer. Rectifiers convert this AC voltage into DC voltage required in the audio device.