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Old 20th October 2011, 01:38 PM   #16851
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To my view
Lech lecha, Joshua.
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Old 20th October 2011, 01:45 PM   #16852
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I have a more cynical take on this, I think what most people are objecting to is very poorly executed analog design post D/A conversion. Possibly the path of least audio harm is the one where the signal passes through the fewest parts possible despite the potential issue of ultrasonic images folding back into the audio band due to intermodulation downstream.
I'd say that the analogue output section of any player or DAC is of critical impact on the overall sound quality. Fewest parts possible is but one thing, however whether the analogue section is built of ICs, discrete SS or tubes and the topology and parts selection also matter.

So, possibly there is no one solution that is a "cure all".
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Old 20th October 2011, 01:47 PM   #16853
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Lech lecha, Joshua.
The same to you.
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Old 20th October 2011, 02:04 PM   #16854
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So, possibly there is no one solution that is a "cure all".
Certainly agree, but there are better solutions than those typically employed.
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Old 20th October 2011, 02:10 PM   #16855
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Originally Posted by DF96 View Post
Not quite true. It is the anti-aliasing filter in the record chain which is truly inevitable. The image filter in playback is only necessary if you want to accurately reproduce the signal found after the anti-aliasing filter. If you are happy with a rough approximation to that signal, then a simpler filter (or no filter) can be used at the playback end.
Let's separate in two cases.

1) In case of oversampling, the digital interpolation filter must cut everything above 22.05kHz, based on principle of oversampling.

2) If no oversampling is used, the brickwall digital filter is needed to make flat amplitude response in audio band. Without such filter, there is -3.92dB at half sampling frequency. And, you create mirror frequencies, that may lay inside audio band.
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Old 20th October 2011, 02:29 PM   #16856
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Certainly agree, but there are better solutions than those typically employed.
Of course, else, all would love all Players and all DAC converters…
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Old 20th October 2011, 02:37 PM   #16857
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Ed, would we lie to you??
jan
Jan,

The question is. "Has your perception been distorted?"

The guy on the left looks more like a cousin than my real cousins do!


Quote:
Originally Posted by PMA View Post
Let's separate in two cases.

1) In case of oversampling, the digital interpolation filter must cut everything above 22.05kHz, based on principle of oversampling.

2) If no oversampling is used, the brickwall digital filter is needed to make flat amplitude response in audio band. Without such filter, there is -3.92dB at half sampling frequency. And, you create mirror frequencies, that may lay inside audio band.
Pavel,

I like the image posted but the output sine wave needs to be right shifted by one time period! Is the book a translated version or original?
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Old 20th October 2011, 02:41 PM   #16858
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Originally Posted by PMA
If no oversampling is used, the brickwall digital filter is needed to make flat amplitude response in audio band. Without such filter, there is -3.92dB at half sampling frequency. And, you create mirror frequencies, that may lay inside audio band.
You are mixing together two issues here. Brickwall filtering (to eliminate images) and sinc-compensation filtering (to compensate for the DAC sinc response) are two separate issues, although they may be addressed in the same filter. 'Mirror' frequencies may arise from analogue circuitry nonlinearity if the brickwall filtering is inadequate.
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Old 20th October 2011, 02:43 PM   #16859
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Originally Posted by simon7000 View Post

The guy on the left looks more like a cousin than my real cousins do!
I think I've just been dissed.
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Old 20th October 2011, 02:54 PM   #16860
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Of course, else, all would love all Players and all DAC converters…
I have now verified that a $54 Sandisk mp3 player sounds inferior to SY's DAC even at 320K. Now to move up the cost ladder. I have to admit my HD600's directly into my stock Dell E6500 would require a careful DBT.
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