L.K.S MH-DA006 ES9039pro Digital to Analog Convertor (DAC)

DA006 is a new generation of flagship DAC developed by Musetec over three years and launched in 2024. During this period, it has undergone more than ten revisions and adjustments.

Compared to the previous DA005, the listening experience of DA006 has been improved in all aspects. DA006 has clearer and richer details, a stronger sense of texture, a more stable sound base, better detail control, a wider soundstage, fuller and more powerful, smoother and more natural.

DA006 uses a total of 6 high-quality O-type transformers to power different functional circuits. It has a two-layer structure, with 6 transformers on the lower layer and the DAC main circuit on the upper layer. The upper and lower layers are separated by a 4mm-thick metal plate. The upper layer is divided into three areas by two 6mm-thick metal plates, which are the left channel analog area, the digital processing area, and the right channel analog area, respectively. This design can minimize the power crosstalk in different functional areas of the DAC, making the sound purer and clearer.

The Digital part of DA006 has a two-stage power supply design. The first stage is the AC to DC rectifier and super low noise regulator circuit, and the second stage is the multiple sets of LDOs to supply power to each functional circuit. The second stage power supply is refined using multiple sets of LDOs according to functions. There are a total of 19 sets of ultra-low-noise LDOs. For example, 3 sets of TPS7A94 with an output noise of only 0.46 uVrms are used to supply power to the digital-to-analog conversion parts and the clock part. The AC to DC rectification of the analog output part uses high-current silicon carbide diodes and a self-developed fully discrete circuit, which makes the power supply have a very high transient current output capability. Compared to the commonly used linear regulator method, this discrete power supply method makes the listening experience purer, fuller, and more powerful.

DA006 is equipped with multiple customized low-noise clocks of different frequencies to handle digital audio signals of various frequencies. For the input I2S signal, the DAC supports both synchronous and asynchronous clock modes.

The DA006 has a built-in high-quality USB interface, and the clock of the USB interface is completely synchronous with the DAC chip. To isolate the input noise of the USB port, ADI's latest USB2.0 high-speed bus isolator ADuM4166 is used, and a low-noise clock is specially set for it to reorder the USB data. The maximum rate that the USB interface can support is DSD1024 and PCM768.

The analog output circuit design of the DA006 is another very important part in addition to the power system. We have abandoned the common integrated op-amp output method and adopted a complex fully discrete component construction. There are 11 groups of discrete component circuits on the left and right channels respectively. Carefully select high-quality transistors, use highly stable thin-film resistors, and reasonably adjust the working parameters of the circuit to make all levels of circuits work in Class A mode. Compared to the common integrated op-amp output method, the discrete output circuit of DA006 has an all-round listening advantage.

To achieve satisfactory sound performance, we have spent a lot of time on the selection of basic materials such as capacitors, resistors, and solder. For example, we have used electrolytic capacitors from Mundorf, copper foil capacitors from Duelund, 5N pure silver wires in many places, and the soldering materials (solder, solder paste) have also been selected by listening comparisons.

The design of all functions of the DA006 only takes up one-fifth of the entire design period, or even less. A lot of time is spent on the selection of components and the design of the circuit form. The criterion for judging yes or no is based on the actual listening experience, and the test data of the instrument is only used as a reference. An easily verifiable fact is that when we use different capacitors or resistors with the same paper parameters in the circuit and perform comparison tests through an audio analyzer, we cannot see the difference in test results due to the change of these parts, but the change in the listening experience is huge. Therefore, we always believe that some of the data that can be analyzed by the existing audio analyzers can only quantify certain characteristics of the sound signal to a small extent, and the human listening experience is very complex. The limited data that the instrument pays attention to cannot determine the human listening experience. We must spend a lot of time carefully selecting parts. This is also the reason why it takes us a lot of time to make this DAC.

The main features of DA006 are as follows.
1. The left and right channel circuits are designed symmetrically.
2. Fully discrete analog circuit, with a total of 22 circuit units for the two channels.
3. The left and right channels and digital circuits are respectively placed in different areas of the chassis.
4. Different functional circuits use independent transformers for power supply, totaling 6 high-quality customized transformers.
5. Fully discrete high-current power regulator for analog part.
6. Use ultra-fast high-current silicon carbide schottky diodes for analog power supply.
7. The digital circuit part has a total of 19 sets of ultra-low noise LDOs.
8. High-quality metal foil capacitors are selected for the power bypass filter.
9. A total of four high-quality customized clocks.
10. Support synchronous and asynchronous working modes.
11. Built-in high-performance USB digital interface, with the highest supported format of PCM768K and DSD1024.
12. The USB interface is equipped with the latest USB high-speed bus isolator, and uses an internal clock for USB signal reordering.
13. Digital coaxial * 2, AES / EBU * 1, optical * 1, support PCM 192K or DOP64.
14. IIS-E CMOS, IIS-H LVDS digital input, support PCM768K, DSD1024, and the IIS-H port pin assignment is adjustable.
15. I2S digital input, support up to PCM768K, DSD1024.
16. FPGA reorders the input digital signal.
17. Use ESS ES9039pro DAC chips.
18. Single-ended output 2.8Vrms, balanced 5.6Vrms.
19. Total harmonic distortion + noise < -120dB, Dynamic range > 129dB (A-weighted).
20. Dimensions: width 430mm * depth 380mm * height 122mm (including feet).
21. Net weight 13.9kg.