Hi, Thom,
Let's see if we can help determine what's preventing the 176.4 files from playing. Can you provide some additional specific information about your NOS DAC? Such as:
1) What model DAC chip does it utilize?
2) What sample data input interface, and model, does it utilize? I'm presuming it's USB, but perhaps not.
Thanks.
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Is someone forcing you to read something? As far as I know, all forum members are free to read or skip at will. You do have a willpower, don't you?
Unnecessarily Confrontational Posts
The unfortunate downside of idle thread periods, like now, is that they seem to foster unnecessarily confrontational posts from us all. Not referring to anyone in particular, this just seems to become a general issue. The thread is nearly finished, so let's keep communicating in a healthy manner.
Thanks, all.
The unfortunate downside of idle thread periods, like now, is that they seem to foster unnecessarily confrontational posts from us all. Not referring to anyone in particular, this just seems to become a general issue. The thread is nearly finished, so let's keep communicating in a healthy manner.
Thanks, all.
Hi, Thom,
Let's see if we can help determine what's preventing the 176.4 files from playing. Can you provide some additional specific information about your NOS DAC? Such as:
1) What model DAC chip does it utilize?
2) What sample data input interface, and model, does it utilize? I'm presuming it's USB, but perhaps not.
Thanks.
Hi Ken,
This is the DAC
PowerDAC-R - ECdesigns
The DAC is toslink in, should handle 24/192 according to specs.
I'm converting USB - toslink via a converter box based on CM6631A processor. This one should also handle up to 24/192. The converter I tried today with the toslink input on a sabre chip DAC and that worked fine with the 176 kHz files, so the converter with firmware + computer settings + media player settings are ok.
With the ECD DAC, the 176 file seems to lock and play fine in the player, but no sound comes out.. no noise or strange sounds either, just silence..
With the 44 and 88 files, fine sound comes as usual.
I will email John @ ECD, he probably has a good idea what can be the reason.
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Thom,
I had a quick look on DiyAudio and noticed that there are quite a lot of problems with the CM6631 where also the correct firmware version seems to be playing a role.
So it could very well be that this device is causing problems instead of the Power-R Dac.
Foobar is supposed to have a driver that is working properly, but I'm sure you have done your own search.
It would be great when you could join the 88.2/24 versus 176.4/24 test, because the more NOS Dac's doing this test the better, so your contribution would be very valuable.
If I can assist you in any way, let me know.
Hans
P.S. Could you if possible still answer Ken's question what Dac chip is used in your Dac-R ?
I had a quick look on DiyAudio and noticed that there are quite a lot of problems with the CM6631 where also the correct firmware version seems to be playing a role.
So it could very well be that this device is causing problems instead of the Power-R Dac.
Foobar is supposed to have a driver that is working properly, but I'm sure you have done your own search.
It would be great when you could join the 88.2/24 versus 176.4/24 test, because the more NOS Dac's doing this test the better, so your contribution would be very valuable.
If I can assist you in any way, let me know.
Hans
P.S. Could you if possible still answer Ken's question what Dac chip is used in your Dac-R ?
Thom,
First, what an interesting looking DAC from ecdesigns. I haven’t checked on his very long running and popular thread in some time. His products appear to have come very far.
Okay now, just you indicate above, your DAC is capable of plying 176.4kHz@24-bit files. As shown in it’s input specification from the ecdesigns site: Toslink 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz and 192 kHz - 16/24 bit.
I’m uncertain as to what might be causing 176.4 not to play even though you have signal lock. Even though it’s TOSLINK, it’s probably via a glass fiber, so no expected issues there, but that may be an incorrect presumption. In any case, there is the following interesting sentence from the ecdesigns website: With this DAC you can now use any Toslink source as long as it outputs bitperfect data (e.g. no DSP / no MQA / no volume control). While I’m unsure why a bit perfect input stream is required, without doubt, it is. Probably, so that the sample bit-resolution size never exceeds certain data path limits.
Unless someone else here on the thread knows what may be happening, you probably will need to inquire to ecdesigns for guidance with the problem.
EDIT: I only saw Han’s post after submitting this one. Sounds like he might have some insight.
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Hans and Ken,
Thanks for your input.
I did check my settings so that I should be doing bitperfect.
My best guess is that this problem is due to a change I have made in the toslink module mounting to the board.
There is no traditional DAC chip, all discret logic and resistor arrays. The DAC is really good sounding, and the first DAC I have used that I percieve to be totally source immune.
Thanks for your input.
I did check my settings so that I should be doing bitperfect.
My best guess is that this problem is due to a change I have made in the toslink module mounting to the board.
There is no traditional DAC chip, all discret logic and resistor arrays. The DAC is really good sounding, and the first DAC I have used that I percieve to be totally source immune.
Sorry, it is very confusing to me how you seem to interpret the results from these tests, and it is strange that your satisfying conclusion is the same one written in the OP. I did find the tests interesting and worthwhile though.
The final report that summarises the data and what you think it means will hopefully make it clearer.
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With those unhelpful comments, you get to have the last word. I expect not to see another post from you either addressed to, or addressing me. I will certainly ignore them.
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Thom,
Great to hear that you are happy with the sound of your Dac.
When it’s all composed of discrete components with resistor arrays, it must be a R-2R Dac preceded by a toslink to I2S converter.
Hope that you get things under control soon with the USB to Toslink converter.
Hans
Hans,
I got some suggestions from ECD to check, and it turned out my toslink cable/connectors was not good enough.
Excellent news, Thom!
We are pleased to have your participation.
Some unhelpful comments
I dont know any on chip OS that uses 2x rate (or 4x).
Is downsampling/dithering process perhaps removing the artefacts that were creating from upsampling ?
The 88.2kHz test was next, something closer to real world.
There was one NOS user (rather pseudo-NOS PCM1794), dddac. Couldn't discern a difference (even without NOS droop compensation? OS does nothing when properly implemented?), could with roon OS.
With an OS dac you have an internal filter operating at certain multiple of the input rate, is the internal rate changed or maintained depending on input sample rate? Is the internal filter overridden in some circumstances?
Can it be said with any certainty it is PGGB causing the differences in this test with random OS DACs?
Genuinely struggling to understand the reliability of this.
Good developments although not the conclusion to the thread 'What do you think makes NOS sound different?' that I expected at all.
If the OP is satisfied then it served its purpose, I regret sharing any doubts in the first place.
Original test that was used as an indication of artefacts from a 'bad' OS filter, but a typical OS filter doesn't resample to different multiple of the sample rate, and then back again.
PGGB Up/down sampling test, an interesting one. This time the SR multiple is kept the same.
I dont know any on chip OS that uses 2x rate (or 4x).
Is downsampling/dithering process perhaps removing the artefacts that were creating from upsampling ?
The 88.2kHz test was next, something closer to real world.
I don't think results were compiled for this one. No longer blind?
There was one NOS user (rather pseudo-NOS PCM1794), dddac. Couldn't discern a difference (even without NOS droop compensation? OS does nothing when properly implemented?), could with roon OS.
With an OS dac you have an internal filter operating at certain multiple of the input rate, is the internal rate changed or maintained depending on input sample rate? Is the internal filter overridden in some circumstances?
Can it be said with any certainty it is PGGB causing the differences in this test with random OS DACs?
Genuinely struggling to understand the reliability of this.
Good developments although not the conclusion to the thread 'What do you think makes NOS sound different?' that I expected at all.
If the OP is satisfied then it served its purpose, I regret sharing any doubts in the first place.
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Hi Ken,
I feel honoured that my name is mentioned so many time in the post you refer to, so why should I answer?
Hans
Well said, Mark.
As you indicate, the group test results warrant skepticism. I concur with that. Such concerns are certainly legitimate, due to practical and methodological constraints which have been repeated throughout the thread. Including, my frequent acknowledgments of the lack of scientific controls, and the resulting low statistical-confidence of the results. To make very clear, I have no issue with skepticism, or skeptics.
I'm losing patience with repeatedly explaining and debating the constraints with those who seem to feel that they are the first person on the thread to recognize the consequent scientific flaws. I then conclude that such persons have either, overlooked my many disclaimers regarding the validity/questionability of the findings, or are simply looking to engage in an argument. That may be an incorrect presumption of motivation, but at this late stage of the thread, I've no interest in the possibility of debating those issues yet one more time. Perhaps, after I publish the concluding report.
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Hi Ken,
I feel honoured that my name is mentioned so many time in the post you refer to, so why should I answer?
Hans
Hi, Hans,
After reconsideration this morning, I retract my request. Feel free to engage lasercut's inquiries should you actually desire to.
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Ha!
I had never noticed that the EDIT button remains available on a thread's opening post. Probably, because I rarely open threads. Thanks, for the tip.