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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.
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.
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.
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.
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.
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.
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.
???? 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.
Oh, I fully understand their architecture. Just because there is noise shaping in majority of ADCs does not mean at all that they equal DSD64 1-bit encoding. Easy to prove. Here is RME ADI-2 Pro FS being fed a 1 kHz tone at 96 kHz sampling: Oh yes, ADI-2 Pro, with 44.1 kHz PCM input: You...
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:
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.
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.
???? 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.
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.
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.