Asynchronous I2S FIFO project, an ultimate weapon to fight the jitter

[iancanada]

Originally Posted by gvelim

FYI

Interesting startup in the oscillator market Accusilicon, we make ultra-low phase noise XO/VCXO/TCXO ICs
their XO clocks product reported as

12KHz-20MHz RMS jitter: <50fs (122.88MHz)

Very good phase noise floor, do you want to give it a try?

[gvelim]

I wish !

[regal]

Anyone have this hooked up yet ? Any sound impressions ?

I'm building a simple TDA1541A NOS DAC with it first.


See that it needs 6V 500 mA DC, will this be sufficient for both the SPDIF input board and the fifo board? I am assuming there is more regulation on each board, is a simple LM317 pre-regulator sufficient for the DC supply ?

[qusp]

not yet, in the next day or 2 i'll have hooked it up, its not really compatible with my main system that i'm building due to being only 2 channel, but i'll test it out with headphones, so need to rejig the PSU to accomodate it

[regal]

Keep us posted Q, I hope to have a basic NOS 1541 running by end of next week.

[iancanada]

Originally Posted by regal

Anyone have this hooked up yet ? Any sound impressions ?

I'm building a simple TDA1541A NOS DAC with it first.


See that it needs 6V 500 mA DC, will this be sufficient for both the SPDIF input board and the fifo board? I am assuming there is more regulation on each board, is a simple LM317 pre-regulator sufficient for the DC supply ?

Hi regal,

1, The actual current for all the three board is 110ma for the default configuration. 500ma should be enough. However some of the oscillators are very sentive to the PUS noise to keep low jitter putput. If it is possible, using a 6V battery as a reference. That would be very helpful to know if your PUS is good enough. I suspect 317 is not the best for clocks.

2, The 24.576 crystal on the spdif board is just using by DIX9211 internal PLL to make it generating very stable output for high Fs such as 192KHz. Since our fifo replaces the input clock with new clock from the clock board, this crystal has nothing to do with the fifo output.

3, The fifo makes good clock working, as well as bad ones. So, what gonna be change on the sound is totally up to what clock you are using.

4, The FCC/FPC 1.0 cable between the fifo board and the spdif board is just a power supply and control cable. Both master clock and I2S signal has its own cable. Yes, everything before fifo is not that critical. Did you mean the 'BNC' cable U.FL cable? If you just need a couple of U.FL socket, I can drop some to you in a letter. If you think digikey is quicker, go with H9161CT-ND or 931-1107-1-ND

Have fun with your project.

[qusp]

Originally Posted by regal

Keep us posted Q, I hope to have a basic NOS 1541 running by end of next week.

will do, sorry for little misunderstanding in the other thread, thought you were talking about the single crystal on the disposable clock board =) it appears to even come with rubber bands to launch it out the window =) i didnt look at its speed at all since i plan to just use for quick test and set aside (no i wont really throw it away, its cute and may come in handy again for testing some day)

[GOR3]

Originally Posted by regal

Anyone have this hooked up yet ? Any sound impressions ?

I've had it running for a little while now. I run it into a Gamma 2 for the DAC (using a Wolfson 8741). The whole things sounds wonderful. Great detail; great soundstage.
I still have work to do. I'm powering the whole thing, i.e. S/PDIF board, FIFO, and dual-clock board, from a single battery. Also it needs to go into a box. For some reason, SWMBO doesn't think the breadboard belongs in the den. (Although even she was quick to say that it sounded far better than the prior player).
Good luck with your efforts,
George

[regal]

Originally Posted by GOR3

I've had it running for a little while now. I run it into a Gamma 2 for the DAC (using a Wolfson 8741). The whole things sounds wonderful. Great detail; great soundstage.
I still have work to do. I'm powering the whole thing, i.e. S/PDIF board, FIFO, and dual-clock board, from a single battery. Also it needs to go into a box. For some reason, SWMBO doesn't think the breadboard belongs in the den. (Although even she was quick to say that it sounded far better than the prior player).
Good luck with your efforts,
George

What are you guys using for a battery a 6V lead acid (motorcycle battery) or NiCad ?

My plan has switched to using this spdif-fifo with an old Audio Alchemy DAC (PMD100-AD1862) that has a messed up factory i2S input, and plan on using the Sen output stage which will also be battery powered.

[qusp]

2 x 3.3v LiFePO4