iFi Audio ZEN Phono Desktop Phono Stage

iFi Audio ZEN Phono Desktop Phono Stage

 

The ZEN Phono is the fourth product to join iFi’s ZEN Series – a range with a mission to make high-performance audio more accessible than ever. Just like the ZEN DAC, ZEN Blue and ZEN CAN, it delivers a level of specification and performance never before seen (or heard) at its price point.

First and foremost, the noise floor is whisper-quiet - 90/96dB (36/60dB,BAL2V/SE1V,A-weighted) on MM/MC respectively. The Zen Phono is also able to handle MM/MC cartridges from <0.25mv to >2mV, brining true high-end performance and flexibility to the entry sector. Finally, the Zen Phono has the performance and features not found in many other phono stages, such as; Balanced circuitry, Intelligent Subsonic filter (solves warp issues effectively) and 36dB to >72dB of gain.

 

Features

• Regenerated Power Supply
• RIAA EQ at military specification level
• AI Subsonic Filter
• Works with both MM & MC cartridges
• Balanced Circuitry
• iFi/AMR 'OV' ICs
• Panasonic ECPU capacitors
• Texac Instruments ICs
• Class 1 ceramic TDK C0G
• Multi-layer capacitors

 

Take the stage

Every turntable needs a phono stage to amplify the low-level output from a phono cartridge to ‘line level’ and apply RIAA equalisation. Some integrated amps and preamps have phono stages built in, but these vary in quality and are rarely as good as a well-designed offboard phono stage placed in the signal chain between the turntable and a line-level input on the amp.

Designing a truly high-performance phono stage is not an easy thing to do. For one thing, it is difficult to amplify the delicate output from a phono cartridge without also amplifying noise. In addition, the wide variation in output from different cartridges means that many phono stages only work optimally with certain cartridge types. These issues are exacerbated at the entry-level end of the phono stage market, where basic circuit design using common off-the-shelf components often leads to a performance that is adequate at best –okay for entry level, but easily outclassed by spending more.

The ZEN Phono has been designed to push the boundaries of what can be achieved in an entry-level phono stage. Its circuit design is like nothing else at the price, with a range of precisely engineered settings that ensure genuine versatility. Whatever the turntable, whatever the cartridge, the ZEN Phono always delivers a class-leading performance.

 

A question of balance

The ZEN Phono’s circuitry is of balanced, symmetrical dual-mono design –a topology usually reserved for high-end audio products owing to complexity and cost. Balanced circuit design has the ability the reduce noise and crosstalk, thus increasing sonic clarity, and has long been championed by renowned high-end audio electronics engineer John Curl –a man whose analogue amp designs, including several landmark phono stages, have been lauded since the 1970s.

Curl, now a technical consultant for iFi, has worked with iFi’s in-house technical team, headed by Thorsten Loesch, to produce a circuit design of exceptional quality for such an affordable phono stage. A fully balanced, ultra-low-noise design of this kind is unprecedented at such a lowprice point.

 

Sum of the parts

The ZEN Phono’s balanced circuitry contains surface-mounted components of unusual quality in an entry-level design. For example, the capacitors used include TDK C0G and Murata multilayer ceramic types, as well as Panasonic ECPU polyphenylene sulphide film devices –none of these are cheap, but their class-leading ESL (Equivalent Series Resistance) and individual qualities such as high stability and low distortion pay great dividends in terms of sound quality and the accuracy of RIAA equalisation.

In common with many iFi audio products, the ZEN Phono incorporates a custom OV Series op-amp –in this case, the OVA2637. This also contributes greatly to the price-busting audio performance, thanks to ultra-low distortion(0.0001%).

 

Clean power

The best phono stages on the market create their own power supply off the mains, similar to a mains regenerator, in order to amplify the audio signal from the cartridge without adding noise. The ZEN Phono achieves this aim, but notin a conventional way;it creates a power supply with an oscillation frequency of 1.2MHz, which is 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 –exceptional 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 +/-12V DC.

 

High-end features, entry-level price

Phono cartridges vary greatly in their technical characteristics, but few sub-£200 phono stages handle moving coil (MC) cartridges in addition to moving magnet (MM) types, let alone offer further gain adjustment to make the most of whichever MC cartridge the user chooses to employ.

The ZEN Phono is the exception, delivering a range of gain settings from 36dB to 72dB –impressive even in a much more expensive phono stage. There are four gain settings in total: 36dB (MM), 48dB (high-output MC), 60dB (low-output MC) and 72dB (very-low-output MC). This enables the ZEN Phono to take even the more exotic MC cartridge types in its stride.

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.

This is how it works: vinyl cutting lathes incorporate a so-called ‘elliptical filter’, which means that low-level bass on an LP is invariably mono and creates only horizontal movement of the stylus. Therefore, any low-frequency vertical movement of the stylus as it tracks the LP can only be the result of record warp. iFi’s subsonic filter removes the effect of record warp from the vertical plane, doing its job efficiently without the common drawbacks of attenuating any low bass or adding group delay.

 

Ins and outs

As well as the usual stereo RCA inputs and outputs, gold-plated for optimal signal integrity, the ZEN Phono’s rear sports another phono stage rarity –a 4.4mm Pentaconn balanced output. This can be used to connect to an amp or active speakers equipped with a balanced input –either a Pentaconn 4.4mm input, such as the one found on the ZEN CAN analogue headphone amp, or XLR inputs via an adapter. This enables a fully balanced connection that makes the most of the ZEN Phono’s balanced circuitry –no other phono stage at this price level offers a balanced output option.

A grounding terminal is also provided; attach a turntable’s grounding wire to this to avoid ground loop issues that can cause an audible hum. Even the way the ZEN Phono switches between settings has been engineered to ensure sonic transparency, handled by a microcontroller that only ‘wakes up’ when a setting is changed to avoid any sonically deleterious electronic noise.

"The reason I wanted to hear the balanced output is that balanced circuitry offers clear benefits with low level, high gain signal circuits - I know from designing and building all-discrete fully balanced phono stages. And I was thankfully right in this case. Turning up volume there was no noise, no hiss or hum. Such was the silence I worried something was not working. But all was working and the sound that emanated from our ever wonderful electrostatics was many steps up on that from the unbalanced phono socket outputs. Primarily it grew in dynamic stature and control. The first quick-check LP, our re-master of Fleetwood Mac’s Rumours, came over as having a cleanly outlined sound - even in the time domain where I suspect absence of noise and smear improved definition. But now the bass output of our Audio Technica OC9X SH MC cartridge took up a firmer and more visceralpresence, putting controlled power into Mick Fleetwood’s drum kit." (Read More) Hi-Fi World - 5 World Review - 2020

 

Specifications:

• Gain Settings:
  • MC (V Lo) @72dB (+/- 1dB)
  • MC (Lo) @60dB (+/- 1dB)
  • MC (hi) @48dB (+/- 1dB)
  • MM @36dB (+/- 1dB)
• AI Sub-Sonic Filter: Remedies the 'warp' in LP with no negative impact to bass response
• Max Output Voltage (RMS):
  • 20v RMS bal output into 100k (<1% THD & N)
  • 13.5V RMS bal output into 600R (< 1% THD & N)
• Output Impedance: 200 Ohm (BAL), 100 Ohm (SE)
• Signal/Noise Ratio:
  • 94dB(A) MM re 2V BAL/1V UNBAL
  • 80dB(unweighted 80kHz BW) MM re 2V BAL/1V UNBAL
  • 84dB(A) MC Hi re 2V BAL/1V UNBAL
  • 71dB(unweighted 80kHz BW) MM re 2V BAL/1V UNBAL
  • 90dB(A) MC lo re 2V BAL/1V UNBAL
  • 79dB(unweighted 80kHz BW) MC lo re 2V BAL/1V UNBAL
  • 79dB(A) MC vlo re 2V BAL/1V UNBAL
  • 69dB(unweighted 80kHz BW) MC vlo re 2V BAL/1V UNBAL
• EIN (equivalent input noise):
  • 0.6nV|/Hz (unweighted) MC lo/vlo @ -151dBV (A weighted) @141dBV (unweighted)
  • 6.5nV|/Hz (unweighted) MM/MC hi @ 130dBV (unweighted) @119dBV (unweighted)
• Harmonic Distortion: 
  • < -110dB / 0.0003% MM re 2V BAL/1V UNBAL
  • < -80dB / 0.01% MC lo re 2V BAL/1V UNBAL
  • < -86dB / 0.005% MC vlo re 2V BAL/1V UNBAL
• Power Supply: DV 5V / 500mA
• Shipped with UK plugged power supply.
• Dimensions: 117(l) x 158(w) x 35(h)mm
• Weight: 515g (1.14 lbs)
• Warranty period: 12 months

 

About iFi Audio 

iFi Audio is an award-winning audio tech company dedicated to enhancing your music enjoyment. With a mission to improve sound quality and eliminate noise, distortion, and hiss, iFi Audio offers a wide range of products that cater to headphones, speakers, portable audio devices, phones, and TVs. By doing so, they aim to deliver studio-quality audio that allows you to experience music as the artists intended.

Since its establishment in 2012, iFi Audio has been driven by the love of music and a commitment to making a difference in people's lives. With over 50 meticulously designed and manufactured products, they ensure every detail meets their high standards. Sourcing parts from around the world, including Germany, the USA, and Japan, they bring together global expertise to create exceptional audio devices.

At the heart of iFi Audio's business are its customers. They prioritise delivering the highest quality audio wherever you are, whether in the comfort of your home or on the go. Their distribution centre in the USA serves renowned retailers such as B&H and etailz, expanding their global network and reaching more music enthusiasts.

iFi Audio takes pride in its eco-friendly practices, using recyclable materials like aluminium, paper, and recycled plastics for its products and packaging. They strictly adhere to environmental standards, ensuring their components are hazardous toxins-free.

With a focus on Class A analogue circuitry and maintaining the audio signal's integrity, iFi Audio's products offer exceptional performance without compromising environmental sustainability. They believe that how a product looks, performs, and impacts the environment all matter, and they strive to deliver audio solutions that meet these criteria.

Experience the difference of high-quality audio with iFi Audio and immerse yourself in the joy of music.