Zen Blue Bluetooth Streaming DAC

The ZEN Blue is the first Bluetooth receiver supporting all the latest hi-res codecs for the best-quality music streaming from smartphones, tablets, PCs and Macs to any audio system. The ZEN Blue impresses with its sturdy aluminum enclosure, unusual at its price. What really sets it apart is the circuitry within. The sound quality over Bluetooth is the best it can be.

The Technology: Breathtaking Bluetooth
The manner in which Bluetooth is implemented – the quality of signal processing and the circuitry that surrounds it – has a big impact on performance. Not all Bluetooth sounds the same, and iFi engineers their products to obtain the best possible performance from every audio source – Bluetooth streaming included.

All the latest 24-bit-capable Bluetooth audio formats are supported, including Qualcomm’s aptX Adaptive and aptX HD, Sony’s LDAC and Huawei’s HWA. Other codecs covered include regular aptX and aptX Low Latency, AAC (the favored format of Apple iOS devices) and SBC (the ‘plain vanilla’ Bluetooth codec). This means that every possible source device is covered at the highest audio resolution its Bluetooth specification allows.

The LED at the center of the ZEN Blue’s front panel changes color to identify the Bluetooth codec being received, while another LED to the right indicates the sample rate. Qualcomm’s QCC5100 chip can be updated over-the-air, enabling future Bluetooth codecs to be added to the ZEN Blue’s specification.

The ZEN Blue remembers up to seven paired Bluetooth source devices, making it easy to switch from one device to another, with impressive reception range thanks to the Bluetooth 5 specification. The DAC stage handles sampling rates well in excess of the maximum delivered by current hi-res Bluetooth formats. Of the 24-bit-capable codecs, aptX Adaptive and aptX HD support up to 48kHz, while LDAC and HWA reach 96kHz.

Upgraded Implementation
The iFi Bluetooth implementation begins with a state-of-the-art Qualcomm QCC5100 chip to process the incoming data. The ZEN Blue is the first product of its kind to benefit from this new-generation Bluetooth IC.

The Qualcomm QCC5100 offers a ‘system-on-a-chip’ Bluetooth solution, with all functions covered including D-to-A conversion. The ZEN Blue has separate digital and analogue stages. To feed the analogue stage, the processed digital signal is routed from the QCC5100 to a specialized DAC chip from ESS Technology’s Sabre family to convert the signal from digital to analogue.

One of the key advantages of the ESS Sabre DAC chip is its Hyperstream architecture with integrated Time Domain Jitter Eliminator. This helps deliver low distortion and high dynamic range. It allies with the Qualcomm chip to deliver Bluetooth audio that sounds far better than the norm.

Perfectly Balanced
None of this would mean much if the rest of the ZEN Blue’s circuitry were not up to scratch. This is the first iFi product to benefit from the input of legendary audio designer John Curl. He has teamed up with iFi’s electronics design team, led by Technical Director Thorsten Loesch, to ensure the circuit design of every product is fully optimized.

The ZEN Blue’s analogue output stage is a balanced design, which means less interference and cross talk. It incorporates a range of high-quality circuit components, carefully selected for their performance in an audio context, including professional-grade balanced line drivers, C0G capacitors from TDK and a precision low-noise power supply IC from Texas Instruments.

The Best of Both Worlds
The ZEN Blue adds high-quality Bluetooth reception to any audio system via analogue or digital cable connections. A switch at the back dictates how the digital signal is routed; either through the DAC and analogue output stage, or directly to the digital outputs.

On the analogue side, RCA stereo outputs allow connection to amplifiers, active speakers and more. A 4.4 mm Pentaconn output enables balanced signal transfer to amps/speakers equipped with a balanced input – either a 4.4 mm input, or XLR inputs via a 4.4 mm-to-XLR cable. For digital connections, optical and coaxial outputs are provided. These allow connection to anything with a built-in DAC and corresponding digital input, such as an AV amp or an external hi-fi DAC.