With a gracious heart, we would like to announce that both the Tone2 and the Multichannel Audio Module are open source products! Learn more: Tone2 is Open-Sourced!
 
Highlights:
 
Chipsets - XMOS XU208 + ESS ES9038Q2M
High Performance - Up to 32bit 768KHz sampling rate, bit-perfect DSD512, and -118dB THD+N (line-out).
Balanced RCA - Next-generation "balanced RCA line-out" with 3-pin output, sets a new interface standard for the Hi-Fi industry.
Linear Power Supply - Tone2  has a second USB-C (I2S) port that supports 5V linear power supplies for ultra clean signal-to-noise ratios.
Support Bluetooth wireless expansion, compatible with khadas BT Magic Bluetooth module.
 
Description:
 
Tone2 is our second generation Tone Board from Khadas that incorporates a variety of user feedback from our first-gen product, the Tone1. 
 
ESS ES9038Q2M DAC has been paired with two powerful OPA1612 operational amplifiers, and two RT6862 operational amplifiers. 

The Tone2's aluminum enclosure incorporates a hybrid digital/analog volume control knob, allowing you to rely entirely on analog signal attenuation for accurate sound reproduction. With not one, but two USB-C ports, you can connect a 5V linear power supply to the second USB-C port whilst having USB-C data on the first for excellent power-noise isolation. Finally we've added an industry-first balanced RCA line-out. These novel RCA ports have three signal-pins instead of two, yet retain the same size and form factor as regular RCA ports.

This time, we will also provide a Maker Kit version which provides more possibilities for Geeks, DIYers & OEM Customers. The Tone2 Maker Kit provides our customers with a range of expansion and connectivity options. An external power supply can be attached to the 4-pin VIN 
input (bottom).
 
Interfaces:
30-pin 0.5mm FPC Connector: UART, I2S, I2C (MCU)
4-pin VIN Connector: DC Input, Rated Voltage 4.8V-14.0V
40-pin 2.54mm Header: USB 2.0, I2S, UART, 5.0V
14-pin 0.5mm FPC Connector: USB 2.0, I2C (MCU), 3.3V
14-pin 0.5mm FPC Connector: XMOS JTAG, CPLD JTAG
 
Files & Documents:
USB Driver
DFU Tool
User Manual
Specs 
 
What's in the Box of Tone2:
x1 Tone2
x1 USB-C Cable (Type-C to C)
x1 Instruction Manual
x1 Warranty Card
 
Note: For Tone2 maker kit, the USB-C Cable (Type-C to C) is not included in the pacakge.
 
Compatibility (Tone2 Maker kit):
VIM4 
VIM3 
VIM1S
 
Note: 40-pin 2.54mm GPIO Header can be connected to VIM1S/VIM3/VIM4 but DIYers need to solder female connector onto Tone2; 14-pin 0.5mm FPC Header can be connected to VIM3/VIM4 via a T2V Extension Board from Khadas.
 
Accessories (sold separately): 
Bal-RCA to XLR-3 Male 0.2m Converter / 1.0m Cable
Bal-RCA Plugs and Jacks for DIY projects
BT Magic
T2V Extension Board