Well - when i start to think about it, the more problem i get. I still have my PS3 and my BD-Player, where i would be stuck with the same problem - but i could probably run them analog, since i won't need best possible sound there. But with the HTPC i would want to run it through the USB (and FIFO). The thing is, right now i don't own a HTPC, but i will probably buy one in a few months. And i do plan running Ubuntu/XBMC on it. If you get to a solution i would be really happy - since this will be both for music and movies.
There will be MCLK, SCK and WS output at any time from FIFO if the clock board is working, no matter if you have the I2S input. The only thing is that the date line will keep 0 if you have a wrong or no I2S input
. Because the FiFO MCLK and other clocks are independent from input I2S.Ian
There will be MCLK, SCK and WS output at any time from FIFO if the clock board is working, no matter if you have the I2S input. The only thing is that the date line will keep 0 if you have a wrong or no I2S input
Ian
So Ian, just to confirm this, the MCLK rate is just whatever was selected last and only changes when the i2s input changes its 'group' from the 44.1kHz multiples to the 48kHz multiples. So for a non-critical spdif input in RollE2k's case he could use that as mclk and the es9012/8 spdif input will still function?
I had been thinking of how to best word the FIFO-delay wiki section while doing menial metal work on the weekend, this discussion is timely and I think I can spend some time writing that section this week. I was concerned about how I word it so that it doesn't over-emphasise the issue and erroneously bring people to the conclusion that the FIFO won't be suitable for their setup.
If there are other questions for an FAQ type section that need attention let me know and I'll try to write them in the same edit of the wiki page
MCLK frequency settings will keep at last setting if I2S is unlock or lost. The clock board on-board flash will memory that parameter.
Ian
I had been thinking of how to best word the FIFO-delay wiki section while doing menial metal work on the weekend, this discussion is timely and I think I can spend some time writing that section this week. I was concerned about how I word it so that it doesn't over-emphasise the issue and erroneously bring people to the conclusion that the FIFO won't be suitable for their setup.
If there are other questions for an FAQ type section that need attention let me know and I'll try to write them in the same edit of the wiki page
Thank you so much hochopeper, You did good job on the wiki page.
I was so busy last week. I'll try to do something once I get time.
Regards,
Ian
Mate, I think what he means is direct from fifo OR with the PCM adapter or another adapter to get the format correct for the TDA1541. The answer to which I don't know the question and I'll happily defer to those more knowledgable than myself on such matters
That´s what i mean. The TDA1541A limit for BCK (SCK - FIFO out) is 6.4 MHz.
If FIFO´s SCK = 64*FS than we have:
44.1 KHz --> 2.8224 MHz
48 KHz --> 3.720 MHz
88.2 KHz --> 5.6448 MHz
96 KHz --> 6.144 MHz
176.4 KHz --> 11.2896 MHz
196 KHz --> 12.544 MHz
If this above is correct, i couldn´t use the 176.4 and 196 KHz sampling rates.
Good to know that DUC985.
Enjoy your project and let me know if you need any support.
Ian
The SCK will be 64*Fs. You can't use input bck, because the input bck if you are running the fifo belongs to a different clock domain.
Ian
Moving this o-ring discussion to this thread.
Ian, if a test regime could be worked out I might be able to attach an accelerometer to my dual xo board and evaluate things that way, though I don't have any equipment to measure the jitter or even an ADC that will give meaningful results of the DAC output so ... things get challenging there. I do intend to eventually acquire a better ADC for measurement but that project is a bit outside the scope of what I can do with my hobby time in the near future.
In the next few weeks I will see if I can get meaningful results of vibration from an accelerometer and get back to you guys
I will do initial test without cutting the pcb mounts so we can compare results, then after I know I can measure things meaningfully I will have to acquire an array of alternatives for o-rings I suppose (I'm not going to worry about that until I know I can test it though as I was originally planning on leaving the pcb as one and not worrying about o-rings).
Chris
EDIT: I just found a datasheet for the accelerometer that I have sitting idle after an earlier abandoned project - http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00047926.pdf - I have not yet put any thought into it being actually useful for measuring the vibration we're chasing here.
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Moving this o-ring discussion to this thread.
Ian, if a test regime could be worked out I might be able to attach an accelerometer to my dual xo board and evaluate things that way, though I don't have any equipment to measure the jitter or even an ADC that will give meaningful results of the DAC output so ... things get challenging there. I do intend to eventually acquire a better ADC for measurement but that project is a bit outside the scope of what I can do with my hobby time in the near future.
In the next few weeks I will see if I can get meaningful results of vibration from an accelerometer and get back to you guys
I will do initial test without cutting the pcb mounts so we can compare results, then after I know I can measure things meaningfully I will have to acquire an array of alternatives for o-rings I suppose (I'm not going to worry about that until I know I can test it though as I was originally planning on leaving the pcb as one and not worrying about o-rings).
Chris
EDIT: I just found a datasheet for the accelerometer that I have sitting idle after an earlier abandoned project - http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00047926.pdf - I have not yet put any thought into it being actually useful for measuring the vibration we're chasing here.
Thank Chris,
Remember a guy said he can see the mechanical vibration related jitter from jitter measurement. But my socope is not qualified to distinguish that small amount of jitter. Try better tools if it is possible, or measure it from FFT of audio signal after DAC. Hope you have good idea.
Regards,
Ian
Moving this o-ring discussion to this thread.
Ian, if a test regime could be worked out I might be able to attach an accelerometer to my dual xo board and evaluate things that way, though I don't have any equipment to measure the jitter or even an ADC that will give meaningful results of the DAC output so ... things get challenging there. I do intend to eventually acquire a better ADC for measurement but that project is a bit outside the scope of what I can do with my hobby time in the near future.
In the next few weeks I will see if I can get meaningful results of vibration from an accelerometer and get back to you guys
I will do initial test without cutting the pcb mounts so we can compare results, then after I know I can measure things meaningfully I will have to acquire an array of alternatives for o-rings I suppose (I'm not going to worry about that until I know I can test it though as I was originally planning on leaving the pcb as one and not worrying about o-rings).
Chris
EDIT: I just found a datasheet for the accelerometer that I have sitting idle after an earlier abandoned project - http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00047926.pdf - I have not yet put any thought into it being actually useful for measuring the vibration we're chasing here.
If you want to measure the vibration directly, how about trying a capacitive microphone?
Ian