Hi Stijn,I'm running out of things to do..
I moved the power button of BBB to the front panel and hooked up a battery to the BBB in the hope of preventing any accidents.
Other recent additions:
- OTTO-II IS2 switch
- S03 reclocking/isolation board
I've very pleased with the sonic
Truly a flexibility setup! USB, SPDIF, and BBB direct.
I wonder, how well is BBB sounding against WaveIO under this setup? Pity, I ditched my WaveIO soon after I got myself familiar to BBB or Pi I2S direct. No turning back for me since.
Btw, people were commenting on my 11-DAC w.r.t signal path is being too lengthy, and would degrade the sound. Have you done a comparison with/without that I2S switch (OTTO)? Isn't less can sometime mean more?
Chanh
Hi Stijn,
Truly a flexibility setup! USB, SPDIF, and BBB direct.
I wonder, how well is BBB sounding against WaveIO under this setup? Pity, I ditched my WaveIO soon after I got myself familiar to BBB or Pi I2S direct. No turning back for me since.
Btw, people were commenting on my 11-DAC w.r.t signal path is being too lengthy, and would degrade the sound. Have you done a comparison with/without that I2S switch (OTTO)? Isn't less can sometime mean more?
Chanh
I'm aware of the suggested benefits of a short I2S cable run. This is the compromise I've made. Now that everything has settled down a bit the WaveIO sound conciderably less detailed/clear, more muddled and vailed. I still need the WaveIO for my media centre PC.
Hi Stijn,
Your DAC looks very nice now, definitely one of the nicest builds around. Now you can start with a new speaker design.......
How do you describe the ccs mod after burning in? Is it still edgy and bright?
I have just finished destroying and rebuilding my dac stack to do the ccs mod with the boards you send me.
While all was open I did some other mods that I had in mind.
Attached are pictures of the old and new layout.
changes are:
1) CCS board (small green one next to the DAC chip)
2) moved the 8V shunts directly to the Vcc pin of the DAC chip
3) changed 10R resistors in the analog supply feed line for Riken ohm types.
First impressions are: I hear all the new solderings
sound is edgy and bright
This is a phenomenom that I have heard a lot of times before when serious soldering has been done on the design. It will take a day or two to clear up.
But where will it end up?
Regards,
Your DAC looks very nice now, definitely one of the nicest builds around. Now you can start with a new speaker design.......
How do you describe the ccs mod after burning in? Is it still edgy and bright?
I have just finished destroying and rebuilding my dac stack to do the ccs mod with the boards you send me.
While all was open I did some other mods that I had in mind.
Attached are pictures of the old and new layout.
changes are:
1) CCS board (small green one next to the DAC chip)
2) moved the 8V shunts directly to the Vcc pin of the DAC chip
3) changed 10R resistors in the analog supply feed line for Riken ohm types.
First impressions are: I hear all the new solderings
sound is edgy and bright This is a phenomenom that I have heard a lot of times before when serious soldering has been done on the design. It will take a day or two to clear up.
But where will it end up?
Regards,
Attachments
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Very neat work! I'm hoping to put mine into a case over the next couple of weeks and I can only hope it is somewhere near as tidyI'm running out of things to do..
I moved the power button of BBB to the front panel and hooked up a battery to the BBB in the hope of preventing any accidents.
Other recent additions:
- OTTO-II IS2 switch
- S03 reclocking/isolation board
- R-Core 18V 120VA transformer
- & the CCS's of course
I've very pleased with the sonic improvements.
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An externally hosted image should be here but it was not working when we last tested it.
Good stuff. Did you make any changes under the board when you moved the 8v regs?Hi Stijn,
Your DAC looks very nice now, definitely one of the nicest builds around. Now you can start with a new speaker design.......
How do you describe the ccs mod after burning in? Is it still edgy and bright?
I have just finished destroying and rebuilding my dac stack to do the ccs mod with the boards you send me.
While all was open I did some other mods that I had in mind.
Attached are pictures of the old and new layout.
changes are:
1) CCS board (small green one next to the DAC chip)
2) moved the 8V shunts directly to the Vcc pin of the DAC chip
3) changed 10R resistors in the analog supply feed line for Riken ohm types.
First impressions are: I hear all the new solderings
This is a phenomenom that I have heard a lot of times before when serious soldering has been done on the design. It will take a day or two to clear up.
But where will it end up?
Regards,
And yes, you need to get a good few hours/days with the ccs before you lose the edge, but then you should hopefully end up with the best of both worlds : extra detail, but nice and natural
You can configure Media Centre to work with BBB via direct LAN protocol. Upmpdcli will enable this feature, of course, you already knew this!
This configuration has all the attributes, flexibility, great interface, and most important of all no compromise on Sound Quality.
Thanks guys, personally I think my cablerouting is still a mess which shows I’m still very much a beginner.
Hopefully some of you will share some nice boxed up DDDAC’s in the future. I’m looking forward to those
As for the burn-in of the CCS’s, it took a good week before a really natural sound unveiled itselve. What strikes me the most is the revelations I’m getting in the mid-low and upper bass tones with some recordings.
But there always seems to be an edginess beyond an edginess, or a veil beyond a veil.
Stefan, you are right the time to move on to speakers is long over due..
Hopefully some of you will share some nice boxed up DDDAC’s in the future. I’m looking forward to those
As for the burn-in of the CCS’s, it took a good week before a really natural sound unveiled itselve. What strikes me the most is the revelations I’m getting in the mid-low and upper bass tones with some recordings.
But there always seems to be an edginess beyond an edginess, or a veil beyond a veil.
Stefan, you are right the time to move on to speakers is long over due..
Hi James, Stijn,
I had to break a copper path below the pcb for my current setup, I did this already a while ago, I think I put some pictures on this thread somewhere............
As for boxing up my dac I had planned to do this after I am done experimenting. But when is that
Everything is nice and tidy behind a cupboard door so I feel no urge
I had to break a copper path below the pcb for my current setup, I did this already a while ago, I think I put some pictures on this thread somewhere............
As for boxing up my dac
I had planned to do this after I am done experimenting. But when is that Everything is nice and tidy behind a cupboard door so I feel no urge
It's been nearly three weeks since I put in the CCS's and last night I still percieved an improvement in them. These things take an awefull long time to burn in.
@Stefan, no excusses. With you woodworking skills (and neighbours workshop), I'm expecting great things that will do your DDDAC justice..
@Stefan, no excusses. With you woodworking skills (and neighbours workshop), I'm expecting great things that will do your DDDAC justice..
Chanh, I work in ICT/Telecoms and when I come home I want low complexity. I started with Linux in the mid 90'ish with Open BSD and my experience with consumer level “cross platform” multi media LAN protocols is that they are finicky at best. To be honest I still prefer the tactile simplicity of putting in a CD & I'm seriously thinking about building a CD player next, with two buttons, on/off&Start/stop, what else does one need? (playing via the DDDAC off course). That is also why, my DDDAC has no indicator LED’s and just two old fashion style big dials. In the end everything is possible.. when you start hacking machine code..
I'm after a bit of advice.
I moved my DAC while everything was pluged in, I mainly moved the power cable, as I did this I smelled the heart dropping burning smell that no DIY'er wants to smell. Everything is working except the PSU to the WAVI0, The fuse is ok in the WAVI0 PSU and nothing seems to have any burn marks indicating what the problem is.
Any advice would be gratefuly received. Thanks
I moved my DAC while everything was pluged in, I mainly moved the power cable, as I did this I smelled the heart dropping burning smell that no DIY'er wants to smell. Everything is working except the PSU to the WAVI0, The fuse is ok in the WAVI0 PSU and nothing seems to have any burn marks indicating what the problem is.
Any advice would be gratefuly received. Thanks
I would look at the dropper resistor if you have one in the psu, this may have simply gone open circuit. Burning smells are always horrid and getting the smoke back in usually costs money.....see if you can narrow down the smell origin, also disconnect the wave and see if the ps comes back up, could be anything.
Hope all is well.....
Laters,
Drew.
Hope all is well.....
Laters,
Drew.
mm, the fuse is before the droppers.
I would test if you have AC directly after the transformer, DC after the rectifying diodes and DC before and after the fuse (to make sure)
If that is all the case, you Need to follow the voltages furtherdown the "circuit". if it Comes to that you can PM me, I will Support from there
I would test if you have AC directly after the transformer, DC after the rectifying diodes and DC before and after the fuse (to make sure)
If that is all the case, you Need to follow the voltages furtherdown the "circuit". if it Comes to that you can PM me, I will Support from there
Hi,
I'm still trying to determine, how / why these "stairstep-patterns" come from in my 4-Deck DDDAC (see post #3729). In order to do so, I first checked the I2S signals coming out from the RPi and at the input of the DAC-boards, just to make sure that there is no error in the digital domain.
In order to do so I had to create bit-perfect test signals (sine, square...) which was not that easy. In case you are interested, you can read my blog post regarding this topic here:
Creating PCM-Wave Test Signals With Python | Himmelbauer IT Blog
So, at least this proves that the RPi plays 16-bit PCM bit-perfect, no bit is lost. When having a look at the I2S signals right at the input of the DAC boards, everything looks very nice. The first two samples are the following:
Sample 2: left: 4652 | 0001 0010 0010 1100 | right: 4652 | 0001 0010 0010 1100 |
Sample 3: left: 9211 | 0010 0011 1111 1011 | right: 9211 | 0010 0011 1111 1011 |
One can see the bit pattern in the following three screenshots:
So, everything works as expected, the I2S signal is perfectly shifted into the DAC decks, I'd say.
So, I think there is no error in the digital domain, the reason for the stairstep pattern seems to lie somewhere else, probably it's some internal stuff going on inside the PCM1794, but I have to investigate this further...
I'm still trying to determine, how / why these "stairstep-patterns" come from in my 4-Deck DDDAC (see post #3729). In order to do so, I first checked the I2S signals coming out from the RPi and at the input of the DAC-boards, just to make sure that there is no error in the digital domain.
In order to do so I had to create bit-perfect test signals (sine, square...) which was not that easy. In case you are interested, you can read my blog post regarding this topic here:
Creating PCM-Wave Test Signals With Python | Himmelbauer IT Blog
So, at least this proves that the RPi plays 16-bit PCM bit-perfect, no bit is lost. When having a look at the I2S signals right at the input of the DAC boards, everything looks very nice. The first two samples are the following:
Sample 2: left: 4652 | 0001 0010 0010 1100 | right: 4652 | 0001 0010 0010 1100 |
Sample 3: left: 9211 | 0010 0011 1111 1011 | right: 9211 | 0010 0011 1111 1011 |
One can see the bit pattern in the following three screenshots:
So, everything works as expected, the I2S signal is perfectly shifted into the DAC decks, I'd say.
So, I think there is no error in the digital domain, the reason for the stairstep pattern seems to lie somewhere else, probably it's some internal stuff going on inside the PCM1794, but I have to investigate this further...
Attachments
Has anyone measured the PCM1794A's output distortion versus Vcc supply voltage? I'm wondering how much the distortion of an fixed 200mV to 300mV amplitude range output signal (somewhere comfortably within the compliance limits of the 5V Vcc) improves from increasing the Vcc from 5 Volts to 8 Volts? output signal amplitude is set within the range imposed by the lower Vcc? This question may have been answered somewhere upthread, but I didn't readily find it.
As I was in my "lab" doing some tests, I quickly did this...
Results with a digitally generated 1kHz sinewave directly at I2S input: (I do this with my AP and the digital IO SIA-2322)
0dbFS Signal: d2 -63dB d3 -68dB versus output signal (this is the normal value)
-15dBFS signal (generates 213 mV at output) d2 -90dB d3 -100dB versus output signal
and this measurement produces exactly the same curves on 5V Vcc as with 8Vcc
any way at signals below -6dBFS d2 drops below -80dBand d3 -93dB
I believe in general, distortion with music playing is not at all a point as mostly music is recorded with some headroom
by the way why did you ask?
Results with a digitally generated 1kHz sinewave directly at I2S input: (I do this with my AP and the digital IO SIA-2322)
0dbFS Signal: d2 -63dB d3 -68dB versus output signal (this is the normal value)
-15dBFS signal (generates 213 mV at output) d2 -90dB d3 -100dB versus output signal
and this measurement produces exactly the same curves on 5V Vcc as with 8Vcc
any way at signals below -6dBFS d2 drops below -80dBand d3 -93dB
I believe in general, distortion with music playing is not at all a point as mostly music is recorded with some headroom
by the way why did you ask?
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Hi, Doede,
Awhile back in this thread, I mentioned having also been experimenting with my own design resistor I/V based PCM1794A DAC. I was intrigued by your solution for accomodating a large complience output signal voltage by increasing the PCM1794A's Vcc voltage above the datasheet specified maximum. You may recall I was a bit concerned back then about the potential for shortening the chip's lifespan.
Anyhow, for my next experimental PCM1794A DAC utilizing resistor I/V, I was considering utilizing an increased Vcc as you suggest, except that rather than to gain output signal headroom, I was wondering whether increasing the Vcc above 5 volts could instead be utilized to reduce the distortion of a relatively small amplitude output signal.
However, if I correctly understood your answer, you found no reduction in distortion for a small output signal of say, a few hundred millivolts RMS, as Vcc is increased above 5 V. Is that correct?
Awhile back in this thread, I mentioned having also been experimenting with my own design resistor I/V based PCM1794A DAC. I was intrigued by your solution for accomodating a large complience output signal voltage by increasing the PCM1794A's Vcc voltage above the datasheet specified maximum. You may recall I was a bit concerned back then about the potential for shortening the chip's lifespan.
Anyhow, for my next experimental PCM1794A DAC utilizing resistor I/V, I was considering utilizing an increased Vcc as you suggest, except that rather than to gain output signal headroom, I was wondering whether increasing the Vcc above 5 volts could instead be utilized to reduce the distortion of a relatively small amplitude output signal.
However, if I correctly understood your answer, you found no reduction in distortion for a small output signal of say, a few hundred millivolts RMS, as Vcc is increased above 5 V. Is that correct?
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Thanks for your help Doede, it was a burned out track on the underside of the PSU board, I must have shorted it out somehow when I moved the DDDAC, nothing is screwed down in the case, so it can move around which is not helpful. Time for me to sort this out I think.
ok, see your Point... yes that is correct. if you only need a few hundred mV there is no need for large Vcc. also distortion is very low at that level, so why would you want to decrease that any further.