The hyper-detailed R6 Pro Max is advertisement for HiBy, and also ESS. ES9039Pro's patented Hyperstream pulse-width modulation technology was already a one-up on standard delta-sigma modulation, and now enters its fourth iteration pushing nigh inaudible high-order distortion levels post-conversion further down.
These eight-channel DACs bring five new digital filters – many with low in-band ripple – to the party for new flavours of sonic reproduction.
ES9039Pros pack enough computational horsepower to run their 8x oversampling process in just two passes thus minimising rounding errors – an upgrade on other attempts that use a concatenation of three stacked 2x oversampling passes which compound errors.
Perfectly exploiting the dynamic range and distortion headroom these futuristic ESS DACs provide is HiBy's implementation. An eight-channel current-to-voltage I/V conversion stage is built in to preserve the full information from R6 Pro Max's digital decode.
This overbuilt stage is befitting of ESS chips that output in current for best distortion performance, and indeed more expensive players. By treating each of the eight channel current outputs separately before stereo summing, R6 Pro II yields a small-signal stage that is transparent and, most importantly, accurate.
HiBy's analog signal is then amplified by powerful op-amp buffers that count on their high open-loop gain to boost power over the preceding R6 Pro II by 80 per cent!
This output stage supplies current and means HiBy's muscleman promises high damping factor while maintaining its low distortion into low impedances typical of IEMs, Focals, Fostexs and Rosson Audio Designs. A separately regulated inductor-based power supply ably backs up this potent voltage source.
Still the closed-loop internal gain remaining after the application of negative feedback around R6 Pro Max's op-amp IC analog circuit remains high.
So where she really shines is in swinging voltage, opening up the sound of any high-impedance, 300ohm Sennheiser and ZMF while barely breaking sweat.
All while R6 Pro Max's big 8,200mAH battery keeps you playing back happily for up to 10 hours.
While Android 12 software means it's future-proof for Google Play Store app support of Tidal, Spotify and Apple Music, backed by a Snapdragon 665 SOC processor and 6GB of RAM.
Explore this ESS attempt at the top for all your needs today, or check out the sister – and still just as relevant – R6 Pro II here if you're eyeing pure IEM listening. Also check out all of HiBy's other gear here, or view our music players here.
DAC 2 x ESS Technology ES9039MPro
Amp Op-amp
SNR <130dB
THD <0.0002%