HiBy RS2II Specifications
Hardware Platform
| Category | Chip |
|---|---|
| Main control | Ingenic X1600E |
| Memory specification | 64 MB LPDDR2 (inside X1600E package) |
| Body storage specification | External SPI NAND (for firmware; actual capacity to be confirmed by hardware BOM); music storage uses dual MicroSD cards |
| Wi-Fi | No wireless function |
| Bluetooth | No wireless function |
| LCD | 3.55 inch, 480 × 800 |
| TF | Dual MicroSD card slots; the maximum TF card capacity given in the specification is 2 TB, hot-swappable |
| PMU | AXP2101 |
| Charging | 5 V/2 A adapter input; charging current adjusts with temperature |
| USB | USB 2.0, Type-C, OTG |
| FPGA | PH1P35MEG324 |
| DAC | Darwin III R2R; up to PCM 384 kHz/32 bit, DSD256 |
| Analog amplification | OPA1622 × 4; low-pass filtering uses OPA1612 |
| Battery | 3500 mAh / 3.8 V |
| Knob | Rotate to adjust volume; press to control power and screen |
| Buttons | Fn customizable function key, previous track, play/pause, next track |
| Phone Out | 3.5 mm single-ended |
| Balance | 4.4 mm balanced |
| Line Out | 3.5 mm and 4.4 mm, software switchable |
| Coaxial (S/PDIF) | Output via USB interface |
| Body dimensions | 91.95 × 62.05 × 18.6 mm |
| Weight | Aluminum alloy green version approx. 156 g; copper gold version approx. 240 g |
Software Platform
General Functions
| Category | Specification |
|---|---|
| Operating system | HiBy OS |
| File system support | FAT32, exFAT, NTFS |
| Playback control | Previous track, next track, play, pause, fast forward, rewind |
| Playback modes | List playback, list loop, single repeat, shuffle |
| Song management | Scan TF card audio files |
| MQA | 8× unfolding |
| Equalizer (EQ) | Provides settings entry |
| MSEB | Provides settings entry |
| Darwin | Provides settings entries for digital filter, NOS, harmonic control, etc. |
| Wireless function | Not supported |
| USB DAC | Supports audio input and output |
| USB OTG | Supports connecting external storage devices |
| Firmware upgrade | MicroSD card upgrade, upgrade file is rs2ii.upt |
| Battery life: 3.5 mm PO | > 9.1 hours; screen off playing 44.1 kHz WAV, other settings factory default |
| Battery life: 4.4 mm BAL | > 8.1 hours; same as above |
| Standby | > 787.5 hours; under test conditions listed in the specification |
Output Interfaces
| Output interface | Specification |
|---|---|
| 3.5 mm PO | Single-ended headphone output; high, medium, low three gain levels |
| 3.5 mm LO | Line output; nominal 2 Vrms |
| 4.4 mm BAL | Balanced headphone output; high, medium, low three gain levels |
| 4.4 mm LO | Line output; nominal 4 Vrms |
| USB | USB DAC input or output |
| S/PDIF | Output digital audio via USB interface |
The nominal voltage of the headphone output varies with gain:
| Output | High gain (0 dB) | Medium gain (-6 dB) | Low gain (-12 dB) |
|---|---|---|---|
| 3.5 mm PO | 2 Vrms | 1 Vrms | 0.5 Vrms |
| 4.4 mm BAL | 4 Vrms | 2 Vrms | 1 Vrms |
The high gain test values given in the draft specification are as follows. LO load is 10 kΩ, PO load is 32 Ω; the test values are for different purposes than the nominal voltages in the table above.
| Item | 3.5 mm LO | 4.4 mm LO | 3.5 mm PO | 4.4 mm BAL |
|---|---|---|---|---|
| Output amplitude | 2 Vrms | 4 Vrms | 2.3 Vrms | 4.5 Vrms |
| Maximum power | — | — | 172.5 mW | 630 mW |
| Rated power (THD < 1%) | — | — | 165 mW | 411.8 mW |
| Minimum distortion | 0.0008% | 0.0007% | 0.003% | 0.003% |
| Noise floor | 2.0 μV | 3.5 μV | 1.5–2.6 μV | 2.3–4.5 μV |
| SNR | 120 dB | 120 dB | 119 dB | 120 dB |
| Dynamic range | 105 dB | 105 dB | 105 dB | 105 dB |
| Channel separation | 105 dB | 108 dB | 70 dB | 105 dB |
| Frequency response (-3 dB) | 20 Hz–40 kHz | 20 Hz–40 kHz | 20 Hz–40 kHz | 20 Hz–40 kHz |
Output Audio Specifications
| Format | Sample rate |
|---|---|
| DSD | Up to DSD256 |
| PCM | Up to 384 kHz / 32 bit |
| MQA | 8× unfolding |
Audio File Specifications
The draft specification gives an overall playback limit of PCM 384 kHz/32 bit and DSD256, and does not give independent limits for each file format.
| Audio format | Specification |
|---|---|
| Lossless | — |
| DSD (DSF, DFF, ISO) | Supported; overall limit DSD256 |
| WAV, APE, FLAC, WMA, AIFF | Supported; per-format limit not specified |
| CUE | Supported |
| Lossy | — |
| MP3, OGG, AAC, Opus | Supported; per-format limit not specified |