Hi Audiophile: L.K.S Digital Audio,also known as Musound electronic, professional in the design and manufacture of DAC. After six months of testing and adjustment, in March 2017, Musound finally completed the new es9038pro decoder mh-da004, which is positioned as the flagship of the series. The new flagship machine integrates the experience of Musound in the past decade and the use of many high-end parts, For example, Mundorf MCAP gold electrolytic capacitor, Crystek femtosecond clock, Guhe power socket, Cardas rhodium plated audio stand, AudioNote gold and silver alloy solder and Mundorf Supreme are used in key positions in Germany The flagship gold and silver solder has laid a very good sound foundation for this new decoder. At the same time, after repeated listening and adjusting by many fans, it makes the sound very natural, fax, excellent on-site feeling, rich details, high definition and transparency, abundant sound density, huge dynamic state, and the ductility of high and low frequency poles is very good. First of all, the shortcomings of the previous es9018 / 9028 in the sense of hearing have been improved, and the comprehensiveness of sound quality has reached a new height.More over,by Feb,2020, we have upgraded the USB module inside the DA004 to be equal to the independant device L.K.S digital audio USB-100 with Amanero solution, it means if the user buy the upgraded USB version of DA004, it is no longer necessary to buy and independant Amanero USB-100 again. Mh-da004 provides two configuration versions: The first is the Standard Version, which uses Italian amanero USB module. The module uses ordinary active crystal oscillator and is not equipped with independent power supply. When it is used, the USB module supplies power from the USB port of the computer after connecting the decoder and the computer through the USB cable. The second is the USB upgrade version. The upgrade version improves the two most critical positions that affect the sound -- power supply and clock. Musound uses two expensive Crytek Cchd-957 ultra-low time base jitter active clock, and separately designed a ultra-low noise linear power module for the work of USB. This power module is directly powered by the AC transformer of the decoder, which can greatly optimize the power supply quality of the USB. The upgraded sound has the same characteristics as the high-end CDT, with open sound field, fresh and moist, full, transparent, excellent extension at both ends, The sound is high in density and very delicate, balanced and natural. The non upgraded ones are relatively flat, the high-frequency is slightly rough and protrusive, the texture is insufficient, the low-frequency is masculine but the level sense is insufficient. For those who often use USB to connect computers, it is recommended that you choose the USB upgrade version. The difference between the two versions is only in the USB receiving part, the other parts are completely the same, and the USB part will not affect the performance of other DAC interfaces. ■ product description -———————————————————————————————— Es9038pro is the flagship DAC audio decoder chip of ESS company, and also the DAC chip with the highest performance index. According to the practice of Musound, two es9038pro each are used to work in mono mode, which makes the two DAC chips handle the left and right audio content independently without interference, greatly improving the performance and hearing effect of the DAC. The official index of mono mode is 140dba dynamic range, which is 3dB higher than 137dba of single chip working in mono mode. The official index is only for reference, but it is easy to see the fact that in mono mode, the signal output current of DAC is twice as high as that in the Dual-track mode, and because the power supply of left and right channels can be separated, the darkness of the sound background, the density, separation, dynamic and imaging of the sound can be significantly improved. As is known to the experienced audiophile, DAC chip is only the basis of a machine, the most important thing is the design and adjustment of peripheral circuits. In order to achieve the best sound replay effect by using es9038pro, Musound uncompromisingly designs the peripheral circuits, such as using two high-quality transformers to realize six groups of AC power supply, a total of 13 groups of low-noise voltage stabilizing circuits（ Many key parts use two-stage voltage stabilizing method). The second stage voltage stabilizing adopts the most high-performance power supply chip in the industry to provide the power supply with enough current margin, quick response and ultra-low noise. At the same time, in order to deal with the super current output (signal current over 100mA) under the unique mono mode of es9038pro, Musound specially designed the IV conversion circuit. This part of the circuit is a pure discrete part design, and the base materials used are audio triode, twin field effect transistor, audio medium power transistor, etc. with very low noise index at present. The silver mica capacitor is also used uncompromisingly, The purpose is to obtain the most accurate and natural sound reproduction. Such circuit mode is incomparable by traditional integrated operational amplifier output (such as opa627, ad797, lme49990, opa1612, etc.). Musound designs in the most critical places as follows: 1. For the USB part, Musound always adheres to Italian Amanero solution, which is the leading USB solution in the industry. It is recognized that the sound of it is better than the popular XMOS, and it has been improved by Musound on the basis of the original Italian version. The USB module of the basic board uses six groups of ultra-low noise LDOS for partial power supply (the original version is two LDOS). Besides, in the USB upgrade version, Musound uses two Crytek ultra-low noise clocks to upgrade, and provides a decoder power transformer self powered ultra-low noise stabilized power module to power the USB module. The sound enhancement effect is significant, which is very suitable for the computer audiophile. And so one can save the cost of purchasing an external digital player. 2. The key position of the master clock. Crystal cchd-575 femtosecond clock is used to provide es9038pro with a very low jitter rate (82fs @ 100MHz) clock supply. Experienced audiophile know that when digital audio is restored, the clock is the soul of the system, so the importance of the clock can be seen. For the sake of the purity of the clock signal, Musound starts from the source power supply, uses an independent group of AC power supply regardless of the cost, and supplies the clock separately after passing through two-level ultra-low noise regulators, which greatly improves the quietness of the sound background and the stability of the sound imaging. 3. Musound designed independent power supply for two es9038pro DAC chips working on the left and right channels respectively, so as to reduce the power crosstalk of the left and right channels to a very low state as far as possible, which brings excellent sound separation and extremely accurate sound imaging stability. 4. Musound started to develop discrete circuit to replace the traditional op amp chip three years ago. Because the traditional op amp chip is limited by the chip volume and some congenital factors of SOC integrated circuit, the performance of the single parts that make up the internal circuit is very limited, and the thermal power consumption that can be borne is very low, and the static current of all the integrated op amp chips is in a very low state（ Less than 10mA), even the advanced opa627 gold seal version in the minds of audiophile is not enough to handle the increasing audio output current of es9018 / 28 / 38 (the output current of es9018 / 28 in mono mode is about 30mA, while the output current of es9038 is more than 100mA), so the overall quality performance cannot meet the requirements by the audiophile. The discrete output circuit developed by Musound adopts twin JFET FET input and end pole 3A medium power transistor output, which can easily meet the high current output processing of es9038pro. After more than 100 circuit parameter adjustments in three years, the sound performance is extremely natural, and the ductility of medium, positive, high and low frequency is excellent. 5. It has a high standard analog output circuit. In order to achieve the best effect with this circuit, Musound specially designed a Class A (Class A) power circuit of the same high-grade level, Hengliuyuan circuit mode design, Onsemi high power regulator, and used mondorf electrodialysis, with appropriate output capacitance and decoupling capacitance, the sound is natural, transparent, very balanced and It's very musical. 6. In the high-end system, every tiny detail that affects the sound cannot be ignored. Musound uses Guhe fi03 gold-plated power socket, cardas rhodium-plated RCA Audio output socket, Neutrik balanced output socket and so on. These parts are the most familiar to audiophile. It is precisely the adoption of these key parts that can create a good sound system. Musound is equipped with Swiss Shute frozen fuse as standard for customers. The sound is delicate, warm and quiet. It is obvious that the common fuse is rough and grainy. All ports of MH-da004 DAC support DSD input (coaxial, optical fiber, BNC, AES / EBU support DOP input, USB, I2S support DOP, DSD native source code input) All on-line decoders of Musound are designed with full balance analog circuit. So don't ask if it's true balance. The Italian amanero USB module used in this machine supports PCM and DSD decoding under USB access mode. PCM supports 44.1k ~ 384k various bit rates. DSD supports dsd64, dsd128, dsd256 and dsd512 (Windows). Windows system supports 32 / 64 bit XP / Vista / win7 / win8 / win10, and requires the installation of proprietary drivers (KS / wasapi / WDM / ASIO is supported). Mac OS 10.6 + and Linux uac2 do not need drivers. Thank you for your support to L.K.S Digital Audio! L.K.S Digital Audio is one of the earliest companies in the development of ESS series decoding products in China. It focuses on the development of decoders and has a deep understanding and exploration of ESS series. The products have been customized and developed for many companies at home and abroad since 2012 for more than 5 years, and the customers response are very good. We in line with the attitude of continuous improvement, carefully improve each of our products, and treat each of our customers as the God. Choose us, we will provide you the best service and commitment! You can reach us by our website http://www.mu-sound.com/index.asp or contact me for English service directly through [email protected]. Thanks.