@ Acko and all
I want to use your s03 to connect a BBB (clock disabled) to an DDDac (1794a). Please let me know what pair of clocks from your suggestion will lead to the lowest phase noise / jitter. I've read your explanation on post #1081. So what frequencies / dividers / no dividers to choose? Still not sure which way to go. I want to try and get low phase noise clocks from the Andrea Mori group buy http://www.diyaudio.com/forums/digital-line-level/261651-well-tempered-master-clock-building-low-phase-noise-jitter-crystal-oscillator.html. In addition: What would be the best way to connect the clocks to the S03?
Thank You
Hans
I want to use your s03 to connect a BBB (clock disabled) to an DDDac (1794a). Please let me know what pair of clocks from your suggestion will lead to the lowest phase noise / jitter. I've read your explanation on post #1081. So what frequencies / dividers / no dividers to choose? Still not sure which way to go. I want to try and get low phase noise clocks from the Andrea Mori group buy http://www.diyaudio.com/forums/digital-line-level/261651-well-tempered-master-clock-building-low-phase-noise-jitter-crystal-oscillator.html. In addition: What would be the best way to connect the clocks to the S03?
Thank You
Hans
Excellent work! Really impressed
I am assuming that you have successfully played both 44.1 and 48k-based music
Your build looks correct, especially the position of the clocks. I am bit surprised that you needed to reverse the selection. Thought CKSEL line is low for 44.1k and goes high for 48k- based frequencies. Please check the lines again for both settings.
Yes, I have indicated 22.xx/24.xx for DACs like PCM 1794 that goes up to 192k only. So better to take advantage of the typically lower phase noise of oscillators around these frequencies. So far no actually comparisons have been made but worth a try. I am actually doing a build using 22/24 for James so will post pics soon.
No dividers required for this case.
The S03 was designed quite a while ago with board mounted oscillators mainly but you can also remove them and connect external clock directly to the clock pin pads on board. Also, you will need to tap the CKSEL lines to switch the external clocks. I am sure Andrea Mori's clocks can be connected this way.
Thanks, my new hot air rework station and some soldering paste, made the fiddly job a lot more straight forward and enjoyable. This board made me acquire some new skills.
I've played 44.1K, 96K and 192, I don't have much encoded in 48K.
I'll revisit the cksl lines and setting again, just to make sure.
It's a small disappointment for me. The prefix SUPER made me think it would be more complete, with all signals insulated, reclock, appropriate power supply for oscillators, maybe RJ45 connectors and / or HDMI to connect Dac as PS Audio, ......
It might be a good idea to open a new thread for a MEGA CAPE and see if there is interest in something really "complete".
Regards
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Already tried as it happens
I believe the original 192k spec of the DDDAC 1794 was due to the limit of the original WaveIO, but once the updated xmos firmware was released for that, 384k was no problem. Using a wandboard running csos with upsampling using sox and the WaveIO, I can output at 384k and the DDDAC plays it with no issue
Are you serious? Acko never said it would be with everything - and have from beginning said it was for use with S03. Plus, it would be quite stupid to reclock at source, then go over a hdmi to the dac, since you'll end up with jitter on the way. Of course it would be good if there was isolation on the board for those who wont run in same case as dac, but if everyone that has a specific request got it through, then the boards would probably be VERY large, and thus more expensive and harder to get a good layout!
Of course I'm serious. How many BBB have been sold?. How many SO3 has sold acko? How many SO3 have acko in stock?
I think there are many users beggle those who may be interested in a more complete and more versatile product.
In addition, there are countless BBB users who do not know supercape because this thread is called Amanero Isolator/Reclocker GB
It´s your oppinion.
I call that market research.
Regards
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I celibrated to early. It turned out , my BBB was resampling to 48kHz and not using the S03 clocks, having checked mpd's behaviour in it's logfile
I then went to troubleshoot the various clocksetting options in Miero's Botics build.
As far as I can deduct sofar I seem to have two issues. First my clksel seems to only work "inverted", swapping the leads around doesn't resolve this.
By using the inverted polarity option below, I can play 44.1kHz with the clock feed from the S03 succesfully with sound, but eventhough MPD plays 48kHz based files I don't get any sound from these.
Looking at belows recap I think I can see a patern which indicates the 48kHz feed is not coming through. Something seems to be astray in the clock selection part of the S03 board..
I'm now using snd_soc_botic.ext_masterclk=5, that way 44.1kHz based files use the S03 clock and the rest is handeld by the BBB itselve, untill I can resolve this/these issues
I’ve verified playback in hardware in the mpd.log
+++++++++++
snd_soc_botic.ext_masterclk=2
(external clock for 48k only)
Plays audio_format=44100:24:2, with sound (seesm to indicate reverse polarity)
Plays audio_format=48000:16:2, with sound but to slow. (to be expected)
+++++++++++++
snd_soc_botic.ext_masterclk=3
(external clocks for 44k1 and 48k (needed for cape))
Seems to play 48Khz, but no sound
MPD crashes on playing 44.1KHz, no sound
(Reverse clksel leads, identical behaviour.)
+++++++++++++
snd_soc_botic.ext_masterclk=7
(invert polarity of clock selection switch GPIO0_15)
Plays 44.1KHz (audio_format=44100:24:2)/88.2KHz (audio_format=88200:24:2)with sound!
Plays audio_format=96000:24:2, but no sound
MPD crashes on, audio_format=192000:24:2
+++++++++++++
snd_soc_botic.ext_masterclk=9
(external clock for 44k1 only)
No sound, Seems to play 48Khz, but no sound, crashes on 44.1KHz
I then went to troubleshoot the various clocksetting options in Miero's Botics build.
As far as I can deduct sofar I seem to have two issues. First my clksel seems to only work "inverted", swapping the leads around doesn't resolve this.
By using the inverted polarity option below, I can play 44.1kHz with the clock feed from the S03 succesfully with sound, but eventhough MPD plays 48kHz based files I don't get any sound from these.
Looking at belows recap I think I can see a patern which indicates the 48kHz feed is not coming through. Something seems to be astray in the clock selection part of the S03 board..
I'm now using snd_soc_botic.ext_masterclk=5, that way 44.1kHz based files use the S03 clock and the rest is handeld by the BBB itselve, untill I can resolve this/these issues
I’ve verified playback in hardware in the mpd.log
+++++++++++
snd_soc_botic.ext_masterclk=2
(external clock for 48k only)
Plays audio_format=44100:24:2, with sound (seesm to indicate reverse polarity)
Plays audio_format=48000:16:2, with sound but to slow. (to be expected)
+++++++++++++
snd_soc_botic.ext_masterclk=3
(external clocks for 44k1 and 48k (needed for cape))
Seems to play 48Khz, but no sound
MPD crashes on playing 44.1KHz, no sound
(Reverse clksel leads, identical behaviour.)
+++++++++++++
snd_soc_botic.ext_masterclk=7
(invert polarity of clock selection switch GPIO0_15)
Plays 44.1KHz (audio_format=44100:24:2)/88.2KHz (audio_format=88200:24:2)with sound!
Plays audio_format=96000:24:2, but no sound
MPD crashes on, audio_format=192000:24:2
+++++++++++++
snd_soc_botic.ext_masterclk=9
(external clock for 44k1 only)
No sound, Seems to play 48Khz, but no sound, crashes on 44.1KHz
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It's not my oppinion, it is a fact. People can even hear big differences using u.fl longer than 10cm after reclocking - how do you think maybe 1m cable + soldering spot+extra traces on pcb would affect jitter?
This is especially critical when running higher XO frequencies. Reclocking should be done as close as possible to the DAC, that is a fact.
Of course you do, because you want the feature - which maybe most people don't need?
I think acko probably have based this design on interest for best possible sound, not most versatile design - although he has already taken design input if you read one page back. I didn't see any other input than that either.
I think this is disrespecting the person who puts their time designing boards for us, and then they only get complaints.
Anyway, i'm leaving this discussion now.
SuperCape EOI:
PET-240 x 2
Chanh x2
Acko x1
Stijn001 x1
Emyeuoi x 2
Mull3t x2
Myint 67x1
bk856er x1
Supersurfer x1
RollE2k x1
Crazikid x 1
Nautibuoy x1
DQ828 x 1
Lindamar x 2
iancortez x 1
CAAD x 1
Greg Stewart x 1 (but you knew that, Acko... also, maybe x 2)
IanS1 x 1
tods 1x
wlowes x 1
odem81 x1
PET-240 x 2
Chanh x2
Acko x1
Stijn001 x1
Emyeuoi x 2
Mull3t x2
Myint 67x1
bk856er x1
Supersurfer x1
RollE2k x1
Crazikid x 1
Nautibuoy x1
DQ828 x 1
Lindamar x 2
iancortez x 1
CAAD x 1
Greg Stewart x 1 (but you knew that, Acko... also, maybe x 2)
IanS1 x 1
tods 1x
wlowes x 1
odem81 x1
James, at what point on the board would you suggest, I should take the measurement?
Thanks,
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