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Old 25th July 2012, 06:39 PM   #801
1audio is offline 1audio  United States
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For a price you can get one part. (They will throw the other 1000 in a box most likely. . .) Usually making one or a very few is difficult since not every part makes it from start to finish. 22, 24, 45 &49 are standard parts. For digital audio the lower frequencies can easily be a divide option. Higher frequencies become a different oscillator design. If you look at the plots on the Crystek datasheets for the CCHD 957 and the CCHD950 you will see that the close in phase noise is higher for the high frequency oscillators. Its driven by physics (and the q possible in the resonator). For the 90+ MHz needed for the ESS chips I would use a good doubler circuit (lowest phase noise) from the 45+ MHz oscillators. The additional parts are cheap. A minicircuits xfmr, two diodes and a fast (74AC) gate most likely would do it.
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Old 25th July 2012, 07:21 PM   #802
qusp is offline qusp  Australia
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haha thanks mate, food for thought I had thought about using Jims supergain block from AN67f (LT) but would still be in the same or similar position for covering all F/S without some way to MUX the premultiplier/post-multiplier output

hey Ian: repurposed levelshifting board + chhd957?

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Old 26th July 2012, 11:46 PM   #803
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Quote:
Originally Posted by 1audio View Post
For a price you can get one part. (They will throw the other 1000 in a box most likely. . .) Usually making one or a very few is difficult since not every part makes it from start to finish. 22, 24, 45 &49 are standard parts. For digital audio the lower frequencies can easily be a divide option. Higher frequencies become a different oscillator design. If you look at the plots on the Crystek datasheets for the CCHD 957 and the CCHD950 you will see that the close in phase noise is higher for the high frequency oscillators. Its driven by physics (and the q possible in the resonator). For the 90+ MHz needed for the ESS chips I would use a good doubler circuit (lowest phase noise) from the 45+ MHz oscillators. The additional parts are cheap. A minicircuits xfmr, two diodes and a fast (74AC) gate most likely would do it.
That's a good idea. But the low phase noise doubler would be the key part . Any reference design?

Ian
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Old 29th July 2012, 01:55 PM   #804
regal is offline regal  United States
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Ian, could the board or firmware be rejigged to allow the dual clock board to contain say a 45.1584 plus 98.304 XO's? then the only speeds not covered would be 48kHz and 354.x kHz which in my world are pretty rare
DAT's and DVD's aren't rare.




Ian, is there any news on the PCM conversion board? I counted 3 threads in the last three days on this forum with people asking for a solution not know that your fifo with a pcm converter would be perfect for. With all the focus on the ESS9018 most multibit folks aren't following this thread.
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Old 30th July 2012, 04:06 AM   #805
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Originally Posted by regal View Post
DAT's and DVD's aren't rare.




Ian, is there any news on the PCM conversion board? I counted 3 threads in the last three days on this forum with people asking for a solution not know that your fifo with a pcm converter would be perfect for. With all the focus on the ESS9018 most multibit folks aren't following this thread.
Hi Regal,

Got the I2S to PCB convertor daughter board PCBs.

I'm thinking about your suggestion opening a new thread for this project. Because this project is becoming a universal I2S to PCM convertor, it could not only interface with FIFO KIT but also interface with any I2S sources together with MCLK. All NOS DAC will benefit from this projcet, even TDA1541 . The FPGA/CPLD design is 100% synchronized logic and the output timing will exactlly fit those NOS DACs.

Regards,

Ian
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Old 31st July 2012, 04:48 AM   #806
qusp is offline qusp  Australia
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Quote:
Originally Posted by regal View Post
DAT's and DVD's aren't rare.
A.D.D? you choose to see only what you can argue with and then somehow reply without actually taking it in... quite a feat.

you disagree that I have little need for my audio rig to play 48kHz and 352kHz? you know what? I care not, it matters not

Quote:
Ian, could the board or firmware be rejigged to allow the dual clock board to contain say a 45.1584 plus 98.304 XO's? then the only speeds not covered would be 48kHz and 354.x kHz which in my world are pretty rare

I dont and never will watch DVDs (more likely to be 96kHz these days anyway) on my dac with fifo, I have another dac to use for that via optical spdif, the variable frame delay causes sync issues. This is solvable by delaying the video the same amount, but i'd much rather have a dedicated music system. I watch quite a bit of online movies and TV, which have unpredictable delays that are impossible to account for.

and sorry but DAT not rare? are you kidding me? not rare? haha...

hands up any members using DAT tape with fifo (not you Ian)
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Old 1st August 2012, 11:56 AM   #807
Zoran is offline Zoran  Serbia
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Hi Ian
thanks for the good project.
.
I have few Q
.
1. Are the USB interface board working on Mac OSX. If so give please more info about that?
2. Is there a possibility to have instead I2S which is normaly L/R latched
option for L/L and R/R, or for that purpose 2 pieces of fifo is needed?
3. Is there some posibility to have beside I2S, other digital input formats such as the BB and AD used in their dac chips?
.
thanks
ciao
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Old 1st August 2012, 11:58 AM   #808
Zoran is offline Zoran  Serbia
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Is somewhere some web site to inform about specs...
To avoid reading the very long topic from the beginning
trying to reach the info?
Thanks
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Old 1st August 2012, 12:29 PM   #809
Zoran is offline Zoran  Serbia
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Sorry I forgot to ask:
Will the hardware support some possible new software in the future
or it will deserve a new hardware boards?
thanks again
.
regardless of the answers
probably i will order
the device
.
thanks
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Old 1st August 2012, 12:33 PM   #810
qusp is offline qusp  Australia
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there is no USB interface board
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