Octave Music Don Grusin High Resolution Music Analysis (Video)

[bennetng]

Octave Music Don Grusin High Resolution Music Analysis (Video)

Miska has posted measurements on a few forums over the past many years. Like he said, you need to look around. Even various threads on ASR. Join those threads and ask questions and others with the time can answer. His audience must not have the most basic knowledge of signal...

www.audiosciencereview.com

It is amusing that everyone put the focus on ultrasonic noise without paying attention to stuff below 20kHz. Even Miska's trusted AKM DAC with his trusted modulator and his trusted Prism analyzer showed that DSD256 is about 3dB noisier than 44.1k PCM, so no more excuse about ADC aliasing and such. If the rise of <20kHz noise is really caused by ADC aliasing, then it simply means DSD256 is still noisier than 44.1k PCM, even in a "Miska approved" environment. Archimago got similar results as well:

Do you need linear power supply for DACs?

The tests were done with the same SoX DSD signal with the same modulator settings, so all differences were originated from the DAC. All RMAA tests were done with the ADI-2 ADC, so with this factor being constant, all differences were originated from the DACs under tests. You just don't seem...

www.audiosciencereview.com

Regardless of audibility, the whole DSD upsampling thing is simply a waste of time.

 

[TCD333]

View attachment 196694

It is amusing that everyone put the focus on ultrasonic noise without paying attention to stuff below 20kHz. Even Miska's trusted AKM DAC with his trusted modulator and his trusted Prism analyzer showed that DSD256 is about 3dB noisier than 44.1k PCM, so no more excuse about ADC aliasing and such. If the rise of <20kHz noise is really caused by ADC aliasing, then it simply means DSD256 is still noisier than 44.1k PCM, even in a "Miska approved" environment. Archimago got similar results as well:

Here is a PCM1792 (Mono mode) outputting -150dB signal in DSD64 mode. For DSD256 shift the noise lower and to the right. No in band problems to see here.

 

[bennetng]

Here is a PCM1792 (Mono mode) outputting -150dB signal in DSD64 mode. For DSD256 shift the noise lower and to the right. No in band problems to see here.

You cannot compare graphs with different configurations (FFT size and averaging) and different test signals (frequency and amplitude). These are common sense.

 

[TCD333]

You cannot compare graphs with different configurations (FFT size and averaging) and different test signals (frequency and amplitude). These are common sense.

With -60dB the noise is basically the same. With DSD64 in Mono 9V OP mode the DR will be -130dB. With DSD256 it will reach the chips max of > -132dB. This is far in excess of 16 bit NF. So the format itself is capable of huge DR in audio band. Conversion software and hardware is another issue.

 

[bennetng]

With -60dB the noise is basically the same. With DSD64 in Mono 9V OP mode the DR will be -130dB. With DSD256 it will reach the chips max of > -132dB. This is far in excess of 16 bit NF.

From the same datasheet:

 

[TCD333]

That's correct. You are looking at DSD64 not DSD256.
You were asserting that "DSD256 is still noisier than 44.1k PCM" in band. This is just not the case.

 

[bennetng]

That's correct. You are looking at DSD64 not DSD256

An amusing excuse. Did the datasheet mention the graph you posted is from DSD64 or DSD256?

You were asserting that "DSD256 is still noisier than 44.1k PCM" in band. This is just not the case.

Since you edited your post...
I was clearly commenting Miska's RME AKM DAC measurement results, and it is totally irrelevant to how you interpret the TI datasheet.

 

[Dogcoop]

It has been explained to me that the PCM format may have problems with: glitches, idle tones and some imaging at low levels at a few hundred kilohertz or in the megahertz range. What other problems are there with PCM that I am missing? Ringing? There is incredible technological firepower on display in this thread, but no one has explained why we need to ‘improve’ the PCM format. If someone could explain in a couple of sentences what the problem with PCM is that must be addressed, I will leave this thread a happy man. If the problem with PCM cannot be identified, then there is no need to look for a solution, whether it be DSD or some as yet undiscovered new format.

Happy Listening!

PEACE

 

[mansr]

It has been explained to me that the PCM format may have problems with: glitches, idle tones and some imaging at low levels at a few hundred kilohertz or in the megahertz range.

Idle tones are a DSD problem.

 

[TCD333]

An amusing excuse. Did the datasheet mention the graph you posted is from DSD64 or DSD256?

All DSD measurements in the data sheet are at 64x. In the TI forum, application Engineers couldn't guarantee that it will run higher than DSD64.
However this DAC has successfully been used by people at DSD256 rates and the max DSD clocking spec supports this.

Maybe you could cut the condescending approach and take note that I have spoken to product application engineers and other designers
WRT what this chip can and can't do.

This forum is clearly very anti DSD amongst other things. I'm neither a proponent or a detractor but I do like to understand what it is
capable of and how to best work with it.

TCD

 

[bennetng]

All DSD measurements in the data sheet are at 64x.

Then don't post that graph in the first place.

 

[Dogcoop]

Idle tones are a DSD problem.

What are the other ’problems’ that would be associated with PCM that need to be solved or improved upon?

thnx

 

[TCD333]

Then don't post that graph in the first place.

???? Surely you understand that whatever the NF is at DSD64, it will be lower at DSD256.
You clearly stated that "DSD256 is still noisier than 44.1k PCM". I'm at a bit of a loss why but maybe it
was a response to Miska's input which seems to have polarized a lot of people here.

TCD

 

[pkane]

Octave Music Don Grusin High Resolution Music Analysis (Video)

Miska has posted measurements on a few forums over the past many years. Like he said, you need to look around. Even various threads on ASR. Join those threads and ask questions and others with the time can answer. His audience must not have the most basic knowledge of signal...

www.audiosciencereview.com

View attachment 196694

It is amusing that everyone put the focus on ultrasonic noise without paying attention to stuff below 20kHz. Even Miska's trusted AKM DAC with his trusted modulator and his trusted Prism analyzer showed that DSD256 is about 3dB noisier than 44.1k PCM, so no more excuse about ADC aliasing and such. If the rise of <20kHz noise is really caused by ADC aliasing, then it simply means DSD256 is still noisier than 44.1k PCM, even in a "Miska approved" environment. Archimago got similar results as well:

Do you need linear power supply for DACs?

The tests were done with the same SoX DSD signal with the same modulator settings, so all differences were originated from the DAC. All RMAA tests were done with the ADI-2 ADC, so with this factor being constant, all differences were originated from the DACs under tests. You just don't seem...

www.audiosciencereview.com

Regardless of audibility, the whole DSD upsampling thing is simply a waste of time.

Good point! Here's ADI-2 Pro FS, DSD256 (blue) vs PCM192 (red). Captured by Cosmos ADC @ 192k.

By the way, both, DSD and PCM playing through HQPlayer

Same, but zoomed out

 

[TCD333]

Good point! Here's ADI-2 Pro FS, DSD256 (blue) vs PCM192 (red). Captured by Cosmos ADC @ 192k.

Yes, that looks about right.

The DR spec for AKM DAC in ADI-2 is about 3dB worse in DSD mode.
The Cosmos ADC (used for measurement) is really good. One of the very few ADC's to have very flat noise floor up to 100kHz -> great for
WB measurements.

TCD

 

[bennetng]

???? Surely you understand that whatever the NF is at DSD64, it will be lower at DSD256.
You clearly stated that "DSD256 is still noisier than 44.1k PCM". I'm at a bit of a loss why but maybe it
was a response to Miska's input which seems to have polarized a lot of people here.

TCD

Higher sample rates (and bit depth in the case of PCM) must have a potential to achieve lower noise floor in digital domain, that's for sure. So "DSD256 is still noisier than 44.1k PCM" is a comment to Miska's measurements in analog domain. If you have to interpret my previous post in the way you think, then it is really up to you.

 

[TCD333]

Higher sample rates (and bit depth in the case of PCM) must have a potential to achieve lower noise floor in digital domain, that's for sure. So "DSD256 is still noisier than 44.1k PCM" is a comment to Miska's measurements in analog domain. If you have to interpret my previous post in the way you think, then it is really up to you.

I'd say the 3dB difference in analog domain is probably the RME DAC. If he was using Prism H/W I'd be looking at that. Very unlikely to be HQplayer.


TCD

 

[Music1969]

Good point! Here's ADI-2 Pro FS, DSD256 (blue) vs PCM192 (red). Captured by Cosmos ADC @ 192k.

By the way, both, DSD and PCM playing through HQPlayer
View attachment 196716

Same, but zoomed out
View attachment 196722

Analogue output levels the same ?

In Vrms

 

[pkane]

Output levels the same though?

In Vrms

Yes, the same. In fact, that's why I posted the zoomed out version to show that PCM output was at the same level at 0dBc as it was with DSD.

 

[Music1969]

Yes, the same. In fact, that's why I posted the zoomed out version to show that PCM output was at the same level at 0dBc as it was with DSD.

Is that measuring Vrms of the analogue outputs?

Input signal might be 0dBFS for both, but that's seperate to output level?

And is that ADI-2 in "DSD direct" mode?