Authentication: The need for MQA or other similar idea?

I would not be. Any issuer with a public key certificate can sign, so it comes down to trusting the issuer. You do that when you buy music. I am only interested in well-mastered CD quality releases BTW.

Trust wouldn’t need to be an issue if a more secure means to “A” was established. As @Progisus says,

Cool, TBH same here. I have found some CD quality streams to be better than their hi-res equivalent. I’m presuming they were upsampled from CD.

I only turn to hi-res if I find the CD to sound dull or just a better listen in hi-res. While I can only slightly hear a difference in most cases, I’d like the best sounding either way.

Amazon, Apple, Spotify, Tidal, and Qobuz all stream what is given to them by the music labels. Do ,you really think that these services are taking the music and altering it somehow? Do you thin their contracts allow for that?

Your gasoline analogy is especially poor. It’s like saying all chocolate chip cookies are made using the exact same recipe…

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That would be a bad assumption. If they were just upsampled, at worst, they would sound the same.

There is good up-sampling and bad up-sampling. DACs offer a number of up-sampling filters to choose from (linear phase, minimum phase etc.) Some people think ALL up-sampling is bad and go for NOS DACs (I’m not one of them).

Why is it I find they do sound different? Excuse the poor explanations. Amazon flat, Apple louder, Deezer neutral, Tidal warmer with texture and Qobuz clean, accurate.
Contracts with studios may not allow altering the files supplied, but they could be doing all-sorts with DSP or extra compression to the files supplied.

Just my view via my ears.

Depends if you fine sieve the flour or not. But you’re right, terrible analogy.

What if the FLAC level was 8? More compression, smaller file size, some loss from lossless?

I’m not sure I get this. FLAC is always lossless, regardless of compression level. The lower the level, the faster the encoding; that’s the reason for offering levels.

I’m under the impression the file size is also less, marginally.

I’m a jack of all aspects audio, master of none. You probably have greater knowledge than me. Cheers

Typically, when 24/88.2 or 24/176.4 files are made from 16/44.1 files, it is done using “expansion” which means zeros are inserted. It’s not the same thing as upsampling in the DAC…

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Come on. FLAC is always lossless regardless of compression level so all of the digital data is present when uncompressed.

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No, they are not.

Zero-extension introduces aliasing and must be followed by a low-pass filter. That’s how missing samples are interpolated. I would like to see a piece of software that produces purely zero-extended samples when resampling. Up-sampling in DACs follows the same principle, no reason for it to be different.

How do you know? :slight_smile:

Of course, it is an “interpolation filter”. But the result is not the same as the filters used in DACs.

Because it would require extra work and processing and, therefore, expense on their end. For what gain? It is cheaper and easier to leave the files as received from the record companies.

Storage space?

I just can’t work out why I believe there is/was a difference to me.

DACs need interpolated samples too. I don’t know how you determined that DACs do it differently, they don’t output those intermediate samples. Manufactures do publish the internal filters’ characteristics in the data sheets, and they look like standard low-pass filters to me.

Yes. But the point of the filters in DACs are to do much more than just upsample. They noise shape and my be apodizing, linear phase or minimum phase, etc.

Up-sampling filters in DACs are for up-sampling. Subsequent operations like noise shaping and bit reducing are not linear operations and they don’t qualify as ‘filters’.

That’s exactly why I said they do more than just upsample…the nose shape and filter…jeez.