iFi has added a headphone amplifier to its Zen range of compact components in the Zen Can – an all-analogue design in a compact aluminium chassis. With an RRP of £149, the Zen Can claims a number of features including the ability to drive tough headphone loads, a balanced circuit design, a vanishingly low levels of distortion and versatile sonic tailoring options to optimise performance.
The Zen Can has no digital input of any kind, USB or otherwise. It connects to any audio source with an analogue output, such as the headphone output from a DAP (digital audio player), a laptop, a tablet or a smartphone, or the RCA outputs from, say, a CD player or phono stage. It could be paired with the Zen Blue to add Bluetooth reception, or combined with the Zen DAC to upgrade the DAC’s headphone amp stage. As well as a headphone amp, it can double as a preamp to feed a power amp and speakers or a pair of active speakers.
In the centre of the 15.8cm wide front panel is a smooth-acting rotary volume control, flanked by a range of sockets and buttons. On the left, beside the power button and input switch, resides a control for selecting the appropriate gain. Four settings in 6dB steps – 0dB, 6dB, 12dB and 18db – enable the amp to precisely suit the connected headphones; unity gain (0dB) is useful to ensure low noise with sensitive in-ear monitors, while the higher gain settings make the most of tougher headphone loads, delivering excellent dynamic headroom.
To the right are a pair of headphone outputs – a 6.3mm output for headphones that have a standard single-ended connector (compatible with all headphones) and a 4.4 Pentaconn balanced output for headphones offering balanced connection. An increasing number of high-quality headphones and in-ear monitors either come so equipped or give the option of upgrading to a 4.4mm Pentaconn connector, and this output makes the most of them (it is particularly recommended for high-impedance headphones).
Next to the headphone sockets is a button to engage the latest versions of iFi’s ‘XBass’ and ‘3D’ sonic tailoring options for headphones. XBass adjusts frequency response to enhance low frequency performance – particularly useful with open-back headphones that ‘leak’ deep bass. 3D compensates for the ‘in-head localisation’ effect that often occurs when using headphones to listen to music that was mixed using a pair of speakers, effectively widening the headphone soundstage to deliver a more speaker-like experience. Both XBass and 3D engage purely analogue processing and may be bypassed entirely if preferred.
Around the back, the Zen Can offers stereo RCA and 3.5mm single-ended inputs, plus a balanced 4.4mm Pentaconn input. A 4.4mm balanced output is also provided, to connect to power amps and active speakers equipped with a balanced input – either a Pentaconn 4.4mm input, or XLR inputs via a 4.4mm-to-XLR cable. This balanced output can also be used for single-ended connection if no balanced input is available. All the Zen Can’s inputs and outputs are gold plated for optimal conductivity.
The Zen Can’s circuitry is a balanced, symmetrical dual-mono design – a topology usually reserved for high-end headphone amps. Balanced circuits have long been championed by renowned high-end audio electronics engineer John Curl, now a technical consultant for iFi, given their ability to reduce noise within the signal path. Curl has worked closely with iFi’s in-house technical team, headed by Thorsten Loesch, to produce an analogue circuit of exceptional quality for a device of this kind.
A number of key elements have trickled down from the discrete Class A circuitry developed for iFi’s flagship headphone amplifier. It offers prodigious drive capability for such a modestly priced headphone amp, delivering 1600mW (7.2V) into 32 ohms from the single-ended output, with 15V+ available to loads of 300 ohms or more through the balanced output, ensuring the Zen DAC takes even current-hungry planar headphones in its stride.
The Zen Can’s circuitry utilises many discrete, high-grade surface-mounted components to maximise sonic purity, such as TDK C0G and Panasonic ECPU capacitors, and ultra-low-distortion thin-film resistors. iFi’s custom OV4627 quad-amp stage features four independent FET op-amps using a ‘folded cascode’ design, with low-impedance feedback circuitry to optimise performance.
A further custom op-amp is used for the input stage, which features automatic level matching and feeds a TOCOS precision potentiometer, while the fully discrete, balanced, complementary bipolar output stage utilises the same Class A buffer found in the Pro iCAN. The power supply circuitry includes ‘stealth mode’ voltage conversion, again derived from the Pro iCAN, with linear regulation, noise filtering, physical isolation from sensitive audio circuits and 4,000uF capacitance to keep ample power in reserve to respond to musical transients.
The iFi Zen Can is available from selected retailers. The first 1000 units are bundled with iFi’s ultra-low noise ‘iPower’ AC/DC power adapter, which further enhances performance and costs £49 when purchased separately, at a special package price of £169. When these bundles have sold out, the Zen Can will be available with a standard AC/DC power adapter at £149.