iFi Audio ZEN Phono

Spec’d to make you smile

Unlike any other entry-level phono stage. The ZEN Phono has:

• MM/MC from 36dB >72dB gain. Super-silent noise floor -151dBV
• Precise RIAA with balanced output and performance comparable to +$1k phono stages
• AI subsonic filter. Addresses warp without eliminating bass or causing phase issues

Hissless whisper

Flagship phono amplifiers create their own power supply off the mains, like a mains regenerator. This is fundamental to a well-designed phono stage. Without this, it will struggle to amplify the signal without added noise. This is why phono stages “hiss'' so annoyingly.

Unusually, the ZEN Phono has its own high-tech clean power supply. It creates a 1.2MHz power supply (20,000x mains frequency of 60Hz). In this circuit, a 10uF filtering capacitor = 200,000uF at lower, audible frequencies. With serious levels of noise filtration, it performs at the level of well-designed LC filtering circuits, such the ones found in classic tube amplifiers. Further, located on its own “island” PCB, it is isolated so there is no noise pollution of the analog stage. Just super clean +/- 12V DC at low measured EIN (Equivalent Input Noise) of -151dBV. It is 20dBV quieter than some more well known "Class A+" phonos which are only -131dBV.

Mil-spec RIAA

The EQ circuit uses multiple TDK C0G capacitors in parallel. This is for best stability and the least distortion. They beat polystyrene capacitors and are close to Teflon. Read more here. Already using the lowest tolerance capacitors, combined with multiples in parallel, tolerance is exponentially improved by the square root of the number of capacitors. This is quite a natty circuit design.

The RIAA EQ tolerance level (+/- 0.15dB) is impressive and on par with hand-selected capacitors! The ZEN Phono has some seriously good audio components backing up the fab circuit design which has trickled-down from its ultra-fidelity AMR PH-77 and iFi iPhono siblings.

Super subsonic

The intelligent subsonic filter is from the iPhono range and is quite special. Normal subsonic filters remove “rumble” AND bass, causing phase issues. Their unique AI phono subsonic filter removes “rumble” only.