PCM1704 R2R Isolated nonoversampling NOS Audio DAC with FIFO reclock

R2R, RECLOCK, ISOLATED, NONOVERSAMLING, all mystery area in the audiophile world are now included in an all-in-one compact PCB!

The I2S reclock input circuit in this PCB is based on the Analog Device AN207 stop clock algorithm, left and right channel DAC are latch at the same time. With our enhanced and optimized redesign, it has no phase different problem as the other convertor in the market. The MCK from the I2S input is used to drive the input flip flop for FIFO reclock, it do not have the problem as the other complex reclock scheme which drop or double dozens of unnecessary samples every second, and it do not use CPLD as the other design which actually increase the jitter tenth of time after reclock. This PCB is target for audiophile.

The sound from this DAC is unique, sweet, clear and full of detail that the newest cutting edge delta sigma DAC can never produce. If you haven't taste this kind of sound before it's definitely a regret for an audiophile. It's like compare Vinyl and CD, Rollling shutter and global shutter in the DSLR.

This item includes PCB with all SMT component soldered, thru-hole component are not soldered.

Features:

1) PCM1704 upto 0.0008% THD R2R DAC Chip (DAC chip is not included, purchase separately)

2) Solid ground plane with careful split of digital and analog portion(a must for highest fidelity audio)

3) No Via in active circuit (via inductance always create jitter problem)

4) 0.1% Low noise thin film resistor and C0G Capacitor sourced from Digikey USA (guarantee no fake product from China)

5) Gold plate I2S input connector and four dedicated GND return path for each I2S signal(lowest contact resistance and highest signal quality)

6) The included xmos pcb in the combo is the same as the one sell separately in the store(i.e. flashed with general firmware)

User guide:

1) The PCM1704 PCB can work immediately with only I2S signal and power supply connected, one 3.3V (>300mA), +-5.0V (>100mA) and one +-12V (>100mA).The +-5V power can be supplied by two individual 5V supply. i.e. 5V1 GND1, 5V2 GND2 connected as 5V=5V1, GND=GND1=5V2, -5V=GND2

2)The reclock quality depends on the jitter of MCK, When used with our XMOS PCB, the MCK is connected to the low jitter low phase noise NDK oscillator directly and get the best reclock performance.

3)For windows, set the output to full volume and the same sample rate as the music file for bit perfect non-oversampling NOS audio.

4)Microsoft acquires Pacific Microsonics(inventor of the renowned PMD100 and PMD200 digital filter) at Sep-2000, windows user should enjoy the same sound signature as using PMD100/200 when switch to listen at higher than the original music file sample rate from the system sound control panel using NOS DAC.

5) The included xmos pcb in the combo is the same as the one sell separately in the store(i.e. flashed with general firmware)

6) Double check all the capacitor are installed in the correct polarity before turn on your power supply

7) The thick solder on PCM1704 soldering pad is used for the user easily to install the smt IC and it should not be removed normally.
The normal procedure to install the smt IC:
a) paint a thin layer of soldering flux on the top of the pad which already has thick solder
b) place the IC on the pad
c) use a hot air gun ~340C to blow it from 3-5cm distance. Do not blow it longer than 2min. the IC can be damaged.
d) while the solder melt, the IC should auto align to it's position(due to surface tension from the liquid stage of the solder) If it is still misaligned, user can use a tweezer to move the ic to it's position while the solder is still in the liquid stage. The finish quality of this method will be as good as a computer motherboard.

8) Compact size 80mm x 70mm

Specification:

1) I2S Input: MCK, LRCK, BCK, DATA (*BCK =64x LRCK, MCK >= 2x BCK)

2) Output level: 2V RMS

3) Resolution/Sampling Rate: Upto 16,24,32bit / 384KHz (the most significant 24bit is played, *384kHz playback requires MCK>=49.152MHz and our CM6631A PCB is tested and work)

4) Supply: Regulated 3.3V, +-5V, +-12V

This item is in limited stock, maximum two per buyer. Please contact us if you want to buy more than two, thanks.

Please refer to the TI official website's authorized reseller list for trusted PCM1704 source to avoid bad chip, fake chip, remark chip and recycle chip that is flooding in the market:

http://www.ti.com/product/PCM1704/samplebuy

https://www.rocelec.com/search?q=pcm1704

As of 2015-9-9, Rochester Electronics has 920pcs PCM1704U-K in stock and it is selling at USD61.94 each for quantity from 1-24pcs.