SmartDAC-One

[The Saint]

Originally Posted by Moddang

Hi The Saint,

Your DAC is very intersting. I have some question.

1.
Refer to the block diagram in SRC4392 datasheet at page 40. How do we know how much of X*Fs will gonna be (assumed that RXCKOD is set to be divide by 1)?

The information of PLL2 in datasheet, is unclear for me, stated that
" .... The available PLL2 output clock rates include 512fS, 256fS, and 128fS. The maximum available PLL2 output clock rate for a given input sampling rate is estimated by internal logic and made available for readback via status register 0x13."

We can read the maximum available o/p clock rate at register 0x13 and in term of maximum avialable it sound like we don't know the exact clock rate. For example1, if the status register 0x13 is 512*Fs (suppose to be maximum available) so the o/p clock rate can be 512*Fs or 256*Fs or 128*Fs. For example2, if the status register 0x13 is 128*Fs I'm exactly know that the o/p clock rate must be 128*Fs, right?

Could you please elaborate about my questin on above?

2.
The layout that you posted previously. You split the clock signal from oscillator to SRC4392 and PCM1792, I would like to guest you used 24.576MHz? I seems if the soucre is not 48Khz, 96KHz, and 192KHz then it will be upsampling to be these rate. For example, in = 44.1kHz out = range of 48kHz to 192KHz (upto the setting) ?



Thanks,
Moddang.

Hi Moddang

The SRC4392 in the SmartDAC-One as you have guested operates as a Up Sampler.
It takes 44.1khz, 48khz or 96khz signal and upsamples it to 192khz which it then feeds into the DSD1794A DAC.

Cheers

Anthony

[Rhythm Willie]

Regarding the 12 volt power supply, would you recommend anything?

Would a "highend" power supply improve performance? (something better than a plugpack).

[The Saint]

Originally Posted by Rhythm Willie

Regarding the 12 volt power supply, would you recommend anything?

Would a "highend" power supply improve performance? (something better than a plugpack).

Hi Willie

I use a well regulated linear power supply on my SD, we have had them working
on 12 volt switchers as well and the work well as we have quite extensive filtering on the smart DAC main board.

For the best performance use a linear 12v power supply

Cheers

Anthony
Aussie Amplifiers

[gaetan8888]

Originally Posted by The Saint

Hi Moddang

The SRC4392 in the SmartDAC-One as you have guested operates as a Up Sampler.
It takes 44.1khz, 48khz or 96khz signal and upsamples it to 192khz which it then feeds into the DSD1794A DAC.

Cheers

Anthony

Hello Anthony

Did you try the 1794 dac without the SRC4392 Up Sampler ?

If so, what was the differences in sound quality ?

Thank

Bye

Gaetan

[The Saint]

Originally Posted by gaetan8888

Hello Anthony

Did you try the 1794 dac without the SRC4392 Up Sampler ?

If so, what was the differences in sound quality ?

Thank

Bye

Gaetan

Hi Gaetan

When we first built the SD prototype we used a DIR9001 SPDIF interface chip.
It sounded good but it did not have the upsampling capability and by comparison sounded quite flat and un-interesting.

Just as a side note we have now released the SD for sale as a short form DIY kit and it is available from my web site online shop.
It comes with a pre-programmed IR remote control, you just need to add a 12v DC supply and a case to put it in to get it up and running.
You also get lifetime firmware updates which will be distributed via email and it is updated via the USB port from a Windows or Linux OS.
The USB port currently acts as a mass storage device on the OSs and updating is a matter of dragging and dropping onto the MSD and the firmware is automatically updated.
we will be bringing out more fireware updates soon whereby we will be activating the USB port as a qualified USB Audio device in Windows and Linux, so effectively it will turn the SD into a Windows/Linux Audio streamer.
One other feature will will be doing in the near future is to use the onboard Ethernet port in much the same way as Squeezebox users currently use the same device for Server based audio streaming.
These and other features will be activated via firmware updates as time goes by.

Cheers

Anthony
Aussie Amplifiers

[gaetan8888]

Originally Posted by The Saint

Hi Gaetan

When we first built the SD prototype we used a DIR9001 SPDIF interface chip.
It sounded good but it did not have the upsampling capability and by comparison sounded quite flat and un-interesting.

Cheers

Anthony
Aussie Amplifiers

Hello Anthony

So you replaced the DIR9001 by another SPDIF receiver chip ?

Thank

Bye

Gaetan

[The Saint]

Originally Posted by gaetan8888

Hello Anthony

So you replaced the DIR9001 by another SPDIF receiver chip ?

Thank

Bye

Gaetan

No we designed and programmed the SRC chip as a multi channel SPDIF receiver.
So we do not need any other type of receiver chip onboard.

Cheers

Anthony
Aussie Amplifiers

[Moddang]

Anthony,

Thanks for your reply.

You may need to think about function for non-upsampling

Moddang.