The price includes the brand new TDA1541 chip without A.
Input characteristics:
PCM format: Supports 44.1KHZ-192KHZ/24bit
Input interface: fiber optic AES/EUB、RCA、BNC、 External I2S input
Output interfaces: RCA x2, XLR x2
Automatic mute without SPDIF signal (except for I2s input)
Circuit architecture:
The SPDIF signal receiving chip adopts AK4118, software controlled three digit LED display (individual input channel indication: 1-5), and the external I2s input port adopts a standard 19 pin HDMI socket.
The input signal first enters the SRC circuit for preprocessing, then enters the SAA7220 (disassembled, suffix random), and then enters the CPLD data processing chip. After isolation and digital signal shaping, it is output to the left and right channel DAC chips for decoding.
The single 1541 chip of this machine operates in single channel parallel mode. The decoding of the cold and hot ends of each channel's balanced signal is completed by two 1541 chips, and then output to the corresponding current amplification circuit for pure resistance IV conversion and LPF filtering. After being buffered and amplified by a jfet tube, the balanced audio signal is output.
The RCA output is obtained by adding the balanced output through the HDMA circuit.
This board uses up to twelve sets of high-precision, low ripple precision stabilized power supplies, and the digital signal processing circuit uses two independent stabilized power supplies.
The left and right channels are independently powered (starting from the decoding chip), and an isolation chip is added between signal processing and decoding to reasonably reduce mutual interference between various parts of the circuit.
The rectification adopts fast recovery low internal resistance diodes, the filtering adopts brand new Nichicon electrolytic capacitors, and uses a precision reference voltage source as the voltage stabilization reference, with a discrete component voltage stabilization circuit architecture.
The resistor adopts audio wafer surface mount resistor, and the current amplification part uses tubes and HDMA differential pair tubes, all of which are precisely matched through transistor diagram instrument. The signal capacitor adopts ERO Green Elf, Siemens Thousand Layer Cake, ELNA audio capacitor, Philips, Sibi and other capacitors.
Front panel description:
On the right is the channel switching button.
The middle display screen shows the input channel:
Display CH1) AES input
Display CH2) BNC input
Display CH3 RCA input
Display CH4) fiber optic input
Display CH5) I2s input
Press once to switch input channels and repeat in sequence. The LED on the display screen will cycle from 1 to 5, with signals 1 to 4 constantly on and no signal flashing.
When I2s input (CH5) occurs, the signal lock indicator light remains on for a long time.
Rear panel description:
From left to right are:
Signal section:
1) Right channel XLR output
2) Right channel RCA output
3) I2S input
4) RCA input
5) BNC input
6) Fiber optic input
7) AES input
8) Left channel RCA output
9) Left channel XLR output
Power supply section:
Fuse holder (5x20/3A), power socket, power switch.
Overall dimensions:
Width 430mm, depth 320mm (including input and output sockets), height 78mm (including pin height),
All aluminum chassis.
Weight: 10KG
This machine is powered on and equipped with two EI type transformers, 35W x2.
