The fourth model in iFi’s ZEN Air Series is a phono stage that’s ideal for those who love vinyl records –perhaps returning to the format, as many have done in recent years, or discovering the joy of vinyl for the first time. Not everyone has the funds to invest in a high-end turntable; but that’s fine, because an entry-level deck from the likes of Pro-ject or Rega can deliver fabulous sound – especially when paired with a good phono stage, to make the most of all the detail the needle digs from a record’s grooves.
That’s where the ZEN Air Phono comes in – not only does it offer excellent performance with both MM and MC cartridges, it also delivers an ultra-low noise performance that’s measurably and audibly the cleanest and clearest at its price point – just like its big brother, the award-winning ZEN Phono. This ensures that the listener hears every drop of detail against a super-quiet background.
Like other ZEN Air devices, the ZEN Air Phono simplifies the fully balanced circuit design of its mainline ZEN equivalent but still retains a symmetrical channel layout with high-quality surface-mounted components offering low ESL (Equivalent Series Resistance), high stability and low distortion. This pays dividends in terms of sound quality and the accuracy of RIAA equalisation. In common with many iFi devices, a custom OV Series op-amp is used – in this case, the OVA2637A – further contributing to the price-busting sonic performance thanks to its ultra-low distortion characteristics (THD <0.0001%).
The finest high-end phono stages have their own high-quality power supplies, effectively ‘regenerating’ electricity drawn from the mains to amplify the delicate audio signal from the cartridge without adding noise. Like the ZEN Phono, the ZEN Air Phono achieves this aim but not in a conventional way; its power supply has an oscillation frequency of 1.2MHz, at least 20,000 times that of mains electricity. In this circuit, a filtering capacitor with a 10uF rating is equivalent to 200,000uF at lower, audible frequencies, delivering superb filtering power. The power supply circuitry is located on its own ‘island’ on the circuit board to ensure there is no contamination of the audio signal – just super-clean +/-15V DC.
Features and connectivity
Another rarity at this price level is a subsonic filter, engaged via a front-panel button to tackle the large subsonic signal output caused by warped records. A feature of all iFi phono stages, this proprietary circuit ‘intelligently’ filters out the unwanted subsonic output without affecting any deep bass on the recording – an undesirable side effect of some warp filters.
Connectivity is kept simple: gold-plated stereo RCA sockets in and out, without the 4.4mm balanced output option of the mainline ZEN Phono. A grounding terminal is also provided; attach a turntable’s grounding wire to this to eliminate audible hum.
The ZEN Phono’s four gain settings to suit different cartridge types are replaced by a simple MM/MC switch (40dB/64dB gain). The ZEN Air Phono’s high-gain MC circuit still delivers a remarkable signal-to-noise-ratio of -82dB – no other phono stage at the price comes close.