XMOS XU208
Balanced RCA
ESS ES9038Q2M
Bluetooth Extension
DSD 512 (Native)
Tone2 Maker Kit
PCM 768KHz
HID Volume
High Fidelity Audio
Tone2 utilizes the powerful XMOS XU208 processor with 8 cores & 8 threads for high performance bit-perfect decoding. Decode up to 768KHz PCM and DSD 512 (Native) audio files and enjoy digital master quality audio.
High Performance ESS DAC
Tone2 has been engineered for audio perfection. The powerful ESS ES9038Q2M DAC chip is paired with two TI OPA1612 operational amplifiers and two Ricore RT6862 operational amplifiers.
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’s PCB layout. Two Accusilicon AS318-L 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. This ensures that the time interval of each sample is more stable, so that the analog audio signal can be returned more clearly.
Accurate Reproduction
The analog IV and LPF circuits use two high-performance TI OPA1612 operational amplifiers and two Ricore RT1238 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.
Selecting Power Supply
Tone2 is powered by USB-C (USB) or I2S (Linear Power Supply), with a power path management chip from Texas Instruments. Power selection is easy.
* Linear power supplies require a Khadas-designed USB-C cable, which will be available soon.
Multiple Input/Output Methods
Tone2 has multiple I/O interfaces on its compact chassis.
Input: USB, S/PDIF, Bluetooth (w/ BT Magic)
Output: Balanced RCA, Single-end RCA
With Tone2, you will have the freedom to switch between a variety of audio input and output sources easily.
Total Harmonic Distortion (THD+N):
Balanced RCA: -118dB
Single-end RCA: -116dB
Maximum DAC Line-Output:
Balanced RCA: 4Vrms@200KΩ
Single-end RCA: 2Vrms@100KΩ
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)
BT Magic
BT Magic is a Hi-Fi Bluetooth audio receiver module exclusively engineered by Khadas for the Tone2 series. Experience consistent and interference-free wireless audio, simply plug the module into Tone2’s USB (I2S) port.
Intuitive UX
The RGB light indicates the Bluetooth connection status and encoding format.
Bluetooth
Disconnected
Blue (Flashing)
aptX / aptX LL
Turquoise (Breathing)
Bluetooth
Connected
Blue (Breathing)
aptX HD
Purple (Breathing)
SBC
Yellow (Breathing)
LDAC
White (Breathing)
AAC
Green (Breathing)
Erase
Paring Record
White ((Triple Flash)
Tone2 Maker Kit
More Possibilities for Audiophiles, DIYers & OEM Customers
The Tone2 Maker Kit supports both Makers and OEM (Original Equipment Manufacturer) customers. An MQA-licensed Tone2 DAC is available for OEM customers who wish to use Tone2 in retail products.
The analog circuits of the Tone2 Maker Kit are protected by a shield to block external electromagnetic interference, ensuring a consistent listening experience.
Versatile Expansion
The Tone2 Maker Kit provides our customers with a range of expansion and connectivity options. For example, an external power supply can be attached to the 4-pin 1.2mm VIN input, and OEM clients will have more options such as customized MQA decoding functions.
Tone2 Maker Kit is also competible with Khadas single board computers:
40-pin 2.54mm GPIO Connector:
VIM1S/VIM3/VIM3L/VIM4
14-pin 0.5mm FPC Connector:
VIM3/VIM3L/VIM4
* Only the Tone2 Maker Kit includes additional I/O access via FPC/VIN headers integrated into the PCBA
Interface
Audio Architecture
Performance Parameters
Frequency Respond：
RCA Balanced：±0.2dB（20Hz～20KHz）
RCA Single End：±0.2dB（20Hz～20KHz）
Supported Sampling Rate：
DNR：
RCA Balanced：119dB
RCA Single End：118dB
USB Input：PCM 16-32bit/44.1-768KHz
DSD Native DSD64-DSD512
Coaxial Input：PCM 16-24bit/44.1-192KHz
Resources
User Manual
USB Driver
Reviews
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 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.
How do I adjust the HID (system) volume using the volume knob?
When Tone2 is not at or above maximum volume, turning the volume knob clockwise will increase the device’s hardware volume. Once Tone2 is at maximum volume, continuing to turn the knob clockwise will cause the RGB indicator to flash turquoise 3 times. Continuing to turn the knob clockwise after this point will instead increase the HID (system) volume of your PC.
Multiple Options
Tone2 will come in 2 colors ‘Black’ and ‘Dream Blue’, and it will also be available as a ‘Maker Kit’.
See the differences below:
Tone2
Color：
Black & Dream Blue
Interfaces：
x1 USB-C 2.0
x1 USB-C (I2S)
x1 Balanced RCA (orange) coaxial input
x1 Balanced RCA (white) left channel line OUT
x1 Balanced RCA (red) right channel line OUT
I/O ：
N/A (other I/O will be blocked by the shield case)
Dimension ：
17.00mm(H) x 88.00mm(W) x 61.5mm(L)/ 68.0mm(with RCA)
Tone2 Maker Kit
Color：
N/A
Interfaces：
x1 USB 2.0
x1 USB-C (I2S)
x1 Balanced RCA (orange) coaxial input
x1 Balanced RCA (white) left channel line OUT
x1 Balanced RCA (red) right channel line OUT
Interfaces：
x1 30-Pin 0.5mm FPC
x1 40-Pin 2.54mm header (USB2.0, GPIO I2S, UART, Power)
x1 14-Pin 0.5mm FPC
x1 4-Pin 1.2mm VIN Input (4.8~14V)
×1 14-Pin 0.5mm FPC (Power, USB2.0)
Dimension ：
12.70mm (H) x 82.00mm(L) x 56.00mm(W) /65mm(with RCA)
