Latest Zishan AK4499EQ amplifier DAC MP3 player
What is the largest TF card supported?
The theoretical 2T is limited to the maximum capacity of the current TF card, so the maximum support is 256G.
58mm wide, 80mm long and 24mm thick.
The latest DSDs flagship AK4499 model is upgraded to the AKM AK4499 flagship chip compared to the DSD model DAC. At the same time, the data port is modified to TYPE-C, and a 3.5mm Lineout is added to allow customers to connect to a single-ended amplifier.
I have to say about AK4499:
AK4499 is AKM’s first current-type flagship IC. It is a test of design skills and has very high power consumption. It must be 4 layers or more. The power ripple must be uV and the modulus must be separated. As long as it is an AK4499 product, it must be revised at least 5 times. So AK4499 products are so few and expensive. In order to serve the AK4499, everything follows the simplest design. Except for I/V, LPF, and amp, no analog switch is added. Only the physical relay is used to switch the machine to mute. Even the amp is the simplest BUF634, and strive to restore the AK4499. True color
1. High power consumption leads to less battery life. If the battery is full, the battery life is only a little more than 4 hours, and the heat is serious. If you feel that the battery life is low, you can enter the DAC setting and turn off the Turbo function, so that the AK4499 dual “engine” There is only one “engine” working, so the battery life can be more than 7 hours.
2. In view of the player’s volume and PCB area, only passive LPF can be used, which will increase the impedance of the 2.5mm balance port, so the pro who wants to use the 2.5mm balance port must connect an amp or balance preamp.
Zishan sticks to:
I2S digital signal quality is better.
Zishan likes to keep up with the new. Zishan DSDs uses single-chip STM32F7+CPLD+ dual audio crystal oscillator to realize I2S. This is the same idea as auxe m2 and Qi Rainbow c4 384K 32bit
The analog power supply voltage should be high and the ripple should be good.
The operational amplifier part of the Zishan DSDs analog board provides up to 7V power supply, and 8 Samsung COG MLCCs form a filter pool.
The DAC part of the Zishan DSDs analog board uses boost + high PSRR LDO voltage stabilization + Samsung COG MLCC.
The coupling of Zishan DSDs AK4499 analog board uses audio-specific coupling electrolytic capacitor ELNA Zipao, rejecting MLCC, tantalum capacitor, aluminum electrolysis, etc. for coupling.
HIFI Element Four: Indicators must comply with HIFI.
To test the indicator of the whole machine, under the condition of 44.1K, the lucky player’s index is close to the theoretical value. The index is not based on heroes. The indicator only tells us that the player has no design errors.
The latest 0.5 firmware supports iphone ACC ALAC M4A format
Hardware block diagram
New firmware strikes, spectrum charts, sound spectra, album covers, custom EQs, new UIs, and more update !