Cayin iDAC-8

A modern-day DAC is so much more than its DAC chips, and Cayin have gone the extra mile in hope of everyone seeing the extent of their efforts. 

They ensure the very best platform for Asahi Kasei Microdevices (AKM)’s resurgent flagship DACs to make their mark. Back on their feet with a clean slate, AKM started afresh expanding the basic footprint of a single DAC chip IC into three separate parts – to similarly multiply capabilities by a factor of three.

AKM’s AK4191EQ DSP is the brains of the operation, receiving pristine I2S clocking and data from Cayin's MCU. Aboard, AK4191EQ’s delta-sigma modulator takes advantage of its expanded, dedicated, silicone footprint to lay claim to the title of the first chip IC working at seven bits.

These seven single-bit modulators flow on into Cayin's AKM 4499EXEQ DACs, one for each channel and built with a single purpose in mind: to turn the interpolated, noise-shaped, digital data it receives into the most precise analog waveform possible afforded by its large footprint.

Silicone size matters when it comes to a great DAC IC, and AK4499EXEQ has it. Enabled by much more exact, matched resistors and capacitors aboard for precise DC single-bit decoding, plus dynamic element matching that is less burdened by switching errors – granted by parts accuracy from a bigger footprint.

Any conversion errors from AK4499EXEQs outputting in current manifests as DC offset, and not total harmonic distortion, that is easily filtered out. Current analog outputs are expected of any source claiming to be high performance.

Cayin's current-to-voltage I/V section follows these AK4499EXEQs, befitting of more expensive DACs and indeed chips that output analog in current for best distortion performances. Four 6H6b dual-triodes follow, divided into two separate pairs that each take care of balanced and single-ended outputs respectively.

That's to implement each output specially, with Cayin paying particular attention to iDAC-8's RCAs – with which you can feed their Single-Ended Triode tube amps HA-2A, HA-3A, HA-6A and HA-300B particularly confidently bypassing the latter's input transformers for a cleaner, shorter signal path.

These single-ended tubes operate in parallel and supply voltage gain in the stage where they will make the greatest sonic impact, before getting boosted by a Vishay FET buffer. This transistor preserves triode square law, and lowers output impedance to 60ohms granting iDAC-8's RCAs enough juice to drive downstream amplifiers.

This low output impedance also ensures there's no risk of a high-pass filter forming with the input resistance of another amp. And to further prevent any loss in low frequencies, large coupling capacitors sit at iDAC-8's output to extend its full-range reproduction capably to 5Hz at -3dB.

Phase response is therefore excellent in the human hearing range, preserving taut and fast bass. Its high frequencies also soar above 100Khz for preservation of pinpoint musical imaging, should you ever use this overachiever in a stereo speaker system. Its built-in analog pre-amp also keeps dynamic range high, even when you listen soft.

These little elements in the signal path hint at Cayin's typical attention to detail. Its overbuilt power supply announces their extravagance in material cost building an affordable compact DAC.

An over-specified 45 watt toroidal transformer, nearly 30,000 uF of filter capacitance, linear voltage regulators, dedicated tube and solid-state output supplies plus low-dropout regulators complete this mini-masterpiece of ambitious engineering.

You'll want to connect as many of your digital sources as possible to iDAC-8. I2S compatibility is guaranteed via Cayin's own iDAP-6 and iDAP-8, as well as AES/EBU from Matrix Audio's Element S and iFi Audio's NEO Stream. CD players enjoy AES/EBU and coaxial RCA connections. And even TV audio benefits from its tube stage via optical.

Check out the matching family iHA-8 and HA-2A for iDAC-8 today. Or, view the rest of Cayin's gear here, and our other desktop items here.