Pristine & Authentic Hi-Fi Experience
XMOS XU216 Audio DAC Chip with 16 cores & 16 threads
XMOS XU216 processor for MQA Full Decoder, PCM 768KHz and DSD 512 (Native). Enjoy digital master-quality audio.
ESS High Performance DAC Chip
Tone2 Pro continues with the time-tested ESS ES9038Q2M DAC chip paired with four TI OPA1612 operational amplifiers and three RT6863D power amplifiers at the buffer stage to provide balanced RCA output at ultra-low distortion (0.000126%) . Tone2 Pro can provide high power output and drive up to 300 ohm high-impedance Hi-Fi headphones easily, unlocking the true potential of your headphones for a high-fidelity listening experience.
Multiple Input/Output Methods
Tone2 Pro has multiple I/O interfaces on its compact chassis.
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Input: USB, S/PDIF, Bluetooth (external BT Magic dongle is required)
Output: Balanced RCA, Single-end RCA, 4.4mm balanced jack, 3.5mm single-end jack
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You will be able to manually switch between a variety of audio input and output devices easily.
Patented Balanced RCA
Khadas Balanced RCA is a new connector standard designed by Khadas with a 3-pin audio interface (positive / negative / ground). All metal contacts are gold-plated. Using a Khadas "Balanced RCA Male to XLR-3 Male Hi-Fi Audio Cable", Tone2 Pro is able to output balanced audio to legacy XLR-3 equipment.
Ground (Zero)
Cold Line (Negative)
Hot Line (Positive)
Solid Foundation
for a Low Noise Floor
A pair of low noise LDOs manufactured by ADI supplies power to the operational amplifiers. The DAC's analog output reference supply is channeled through ultra-low noise (1.2uVrms) LDO ES9311Q, with low loss, low temperature drift, and long life film capacitors to ensure the stability and reliability of the power supply, effectively controlling the noise from the original stage.
Precise Clock Management
Various audio components are carefully arranged on Tone2 Pro’s PCB layout. Two Accusilicon AS318-B series, active crystal oscillators with low phase noise and low jitter and one SiTime SiT8209 high performance active crystal oscillator at 100M enhance the low noise characteristics. The phase jitter is controlled within 0.5ps and the frequency drift is only ±10PPM, thus the data can be precisely shaped to achieve a unified clock.
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Ultra-low Distortion
Accurate Reproduction
Two NJU72315 audio volume control chips with extremely low-distortion are embedded in the analog circuit. These chips control the distortion within 0.00016% and provide linear volume control and accurate reproduction of audio sources.
The analog IV and LPF circuits use four high-performance TI OPA1612 operational amplifiers, with 28 high-precision resistors at an accuracy of 0.1% and a low temperature drift of ±25PPM. This provides an accurate and stable RCA output.
Couple Listening
Up to two people can listen together with a single Tone2 Pro. There are two headphone jacks on the right-side, a 3.5mm single-end and a 4.4mm balanced. Listen with those we love.
The headphone jack uses three RT1238Q analog switches with a distortion of 0.000126%. These switches output high-quality audio signals and reduce the loudness of pop noises in the audio stream.
One-Piece Machined Aluminium Shell
The upper shell and knob are made from one-piece of machined aluminum alloy. The logo on the shell and knob are accented with anodized gold. The shape of the chassis is avant-garde while the details comes in a variety of colors to choose from.
Selecting Power Supply
Tone2 Pro is powered by USB-C (USB) or I2S (Linear Power Supply), with a power path management chip from Texas Instruments. Power selection is easy.
Multifunction Knob
Tone2 Pro integrates all its functional operations into the knob, by rotating and pressing the knob, you can select the input methods, change the output volume, and choose different hearing senses.
There is only one knob on the whole fuselage which makes Tone2 Pro concise and beautiful.
External Bluetooth Module
Wireless in Seconds
BT Magic - a dedicated Bluetooth module developed for the Tone2 series which will be available soon supports AAC / SBC /
LDAC / aptX / aptX HD / aptX low latency and other common Bluetooth encoding formats. Tone2 Pro become wireless just in seconds with BT Magic, enjoy a wireless music experience.
Audio Architecture
Performance Parameters
Frequency Respond：
RCA Balanced：±0.15dB（20Hz～20KHz）
RCA Single End：±0.15dB（20Hz～20KHz）
4.4 Balanced：±0.15dB（20Hz～20KHz）
3.5 Single End：±0.2dB（20Hz～20KHz）
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DNR：
RCA Balanced：121dB
RCA Single End：119dB
4.4 Balanced：121dB
3.5 Single End：119dB
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Supported Sampling Rate：
USB：PCM 16-32bit/44.1-768KHz
DSD Native DSD64-DSD512;Dop DSD64-DSD256
Coaxial：PCM 16-32bit/44.1-192KHz
DSD 64（Dop）
4.4 Balanced Output Parameter：
Output Power and Out Voltage：
42mW（5.0Vrms）@600Ω
83mW（5.0Vrms）@300Ω
167mW（5.0Vrms）@150Ω
211mW（2.6Vrms）@32Ω
154mW（1.57Vrms）@16Ω
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THD+N：
-116dB（0.000158%）@600Ω
-116dB（0.000158%）@300Ω
-116dB（0.000158%）@150Ω
-110dB（0.000316%）@32Ω
-105dB（0.000501%）@16Ω
SNR：
121dB
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Crosstalk：
>117dB@32Ω
3.5 Single End Output Parameter：
Output Power and Out Voltage：
8.8mW（2.3Vrms）@600Ω
17.6mW（2.3Vrms）@300Ω
35.3mW（2.3Vrms）@150Ω
125mW（2.0Vrms）@32Ω
114mW（1.35Vrms）@16Ω
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THD+N：
-114dB（0.0002%）@600Ω
-114dB（0.000158%）@300Ω
-114dB（0.000158%）@150Ω
-108dB（0.000398%）@32Ω
-103dB（0.000708%）@16Ω
SNR：
119dB
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Crosstalk：
>69dB@32Ω
Resources
FAQ
Why does Windows require the Khadas USB driver?
The Khadas USB driver provides ASIO support and removes the latency and sample rate conversion issue experienced with the default Windows USB driver for DACs.
What does MQA stand for?
MQA(Master Quality Authenticated) is an award-winning audio codec technology. The master MQA file is fully authenticated for high sample rate audio and is small enough to stream and download.
What is balanced-RCA?
A new balanced audio connector standard, designed by Khadas for small form-factor desktop DACs. It is backwards compatible with standard RCA plugs and cables, more details visit https://khadas.com/balanced-rca
How do I use my existing XLR-3 equipment with Balanced-RCA?
Purchase the Khadas Balanced-RCA to XLR-3 adapter, it is a male Balanced-RCA plug connected to a male XLR-3 plug.
