Qobuz FLAC decompress

[KingRex]

Qobuz high resolution say its FLAC.  Does this mean my server is having to decompress the file to get back to lossless.  I was doing a critical listen last night and my internal WAV 16 44.1 files seem to have more life and realness than the 24 96 FLAC files.

 

I have observed  this before with high resolution files I own.  WAV is better than FLAC.  I attribute it to processing noise in my server.  Who knows the real reason.  

[rickca]

If you use A+ it will decode the FLAC before sending PCM to your endpoint for playback.  Plenty of people have discovered that A+/Qobuz sounds considerably better than the Qobuz desktop app.

[KingRex]

I use Roon HQPlayer. I am finding local 16 44.1 is better than streaming 24 96.  I have to do more listening to really validate that.  Initial impressions are nothing special with FLAC via Qobuz.  

 

I have raved of Qobuz in the past.  Some things have changed in my system. I have much more revealing and natural sounding amps.  Im also Qobuz via Roon rather than Qobuz stand alone.  Stand alone was a hang up nightmare on my machine.  Via Roon its rock solid.  

 

In summation, you are saying my server is seeing this as flac and unfolding it.

 

Thanks  

[rickca]

1 hour ago, KingRex said:

In summation, you are saying my server is seeing this as flac and unfolding it.

I am not saying that because I don't know anything about how Roon does things.  My comment was about A+.

[Cebolla]

My understanding is the Roon Core Server also decodes and plays all audio files that it handles, before the resulting audio signal output is sent over the network to the Roon Endpoint or HQPlayer/Squeezebox/AirPlay 'streamer' - so that would include decompressing Qobuz's FLAC files to PCM before it gets to HQPlayer.

 

Perhaps @Miska can confirm?

 

[Miska]

48 minutes ago, Cebolla said:

My understanding is the Roon Core Server also decodes and plays all audio files that it handles, before the resulting audio signal output is sent over the network to the Roon Endpoint or HQPlayer/Squeezebox/AirPlay 'streamer' - so that would include decompressing Qobuz's FLAC files to PCM before it gets to HQPlayer.

 

Perhaps @Miska can confirm?

 

Yes, that's the case at least with HQPlayer. Due to this you can also play things like MP3/AAC through Roon+HQPlayer although HQPlayer doesn't support those codecs.

 

[bubbamike]

5 hours ago, KingRex said:

Qobuz high resolution say its FLAC.  Does this mean my server is having to decompress the file to get back to lossless.  I was doing a critical listen last night and my internal WAV 16 44.1 files seem to have more life and realness than the 24 96 FLAC files.

 

I have observed  this before with high resolution files I own.  WAV is better than FLAC.  I attribute it to processing noise in my server.  Who knows the real reason.  

FLAC is lossless. 

[KingRex]

3 hours ago, bubbamike said:

FLAC is lossless. 

FLAC is lossless compression like MQA.  My setup is designed to do best up to 24/192 pcm.  No decompressing or upsampling.  Thats my setup.  If I purchase high resolution FLAC,  I need to use DBPoweramp to decompress and turn it onto WAV.  

 

Now I need to find out if I can put Qobuz offline library files onto my drive pre, decomptessed.  

[Cebolla]

44 minutes ago, KingRex said:

My setup is designed to do best up to 24/192 pcm.  No decompressing or upsampling.  Thats my setup.  If I purchase high resolution FLAC,  I need to use DBPoweramp to decompress and turn it onto WAV.  

 

Now I need to find out if I can put Qobuz offline library files onto my drive pre, decomptessed.  

 

Are you running Roon and HQPlayer on the same device or on separate devices?

 

If they are on separate devices, then your concern should be groundless because according to Jussi, HQPlayer is receiving Qobuz's audio already decompressed (by Roon). HQPlayer is considered the 'live' player and Roon 'offline'.

[Kal Rubinson]

23 minutes ago, KingRex said:

No decompressing or upsampling.  Thats my setup.  If I purchase high resolution FLAC,  I need to use DBPoweramp to decompress and turn it onto WAV.  

Can you explain what your setup is?  Why would you need to convert FLAC to WAV?

[Cebolla]

49 minutes ago, KingRex said:

FLAC is lossless compression like MQA.

 

No, MQA is neither compressed nor lossless, but you can losslessly compress MQA using FLAC!

[KingRex]

I have a single server usb connected to my dac. 

 

I have also had an endpoint Roon rendering device attached to my DAC, fed by my server.  It was slightly better.  A little better clarity and top end.    $2500 of endpoint and linear PS was a lot for the uptick at this time. 

[Kal Rubinson]

10 minutes ago, KingRex said:

I have a single server usb connected to my dac. 

 

I have also had an endpoint Roon rendering device attached to my DAC, fed by my server.  It was slightly better.  A little better clarity and top end.    $2500 of endpoint and linear PS was a lot for the uptick at this time. 

So, why convert FLAC to WAV?

[KingRex]

1 hour ago, Cebolla said:

 

No, MQA is neither compressed nor lossless, but you can losslessly compress MQA using FLAC!

How do they differ.  How does MQA get from 16 something to 24 something without decompressing.  There has to be a operation going on that uses computing resources.  

[tmtomh]

23 minutes ago, KingRex said:

How do they differ.  How does MQA get from 16 something to 24 something without decompressing.  There has to be a operation going on that uses computing resources.  

 

FLAC is lossless compression: It shrinks the file size from the original PCM file (i.e. WAV or AIFF), but no audio data is thrown out or permanently changed. When you play a FLAC file, it's not unfolded; it's decoded.

 

MQA is lossy compression plus in many cases lossy downsampling: Any PCM original with a sample rate of 176.4kHz or 192kHz, MQA resamples to half that sample rate (to 88.2k or 96k), throwing out the higher sample-rate data. Then it further compresses that downsampled data into a file that looks like it has half of that sample rate - i.e. 44.1k or 48k. The data above 44.1 or 48k and below 88.2 or 96k is lossy compressed - meaning some of the data is thrown out and the rest is re-encoded - and packed into some of the lower bits of the 16 or 24-bit bit depth of the file.

Then, depending on your playback system, the MQA file is "unfolded" to various degrees in playback. If you have the full unfold and render, then a 24/48 MQA file in the above scenario would be "unfolded" to 24/96, and then the whole thing would be resampled up to 24/192 - although again, the original data is lost forever, so that 96 to 192k resampling simply doubles all the samples in the 96k file. And again, the samples in the 96k file are themselves only a partial representation of the original, because the "folding" process that stuffed a 96k file into a 48k file container necessarily threw out some of the original data.

 

By contrast, a FLAC file throws out none of the data - it simply packs 100% of the audio data into a smaller file than the original, using algorithms to more efficiently store the data.

 

MQA compression is akin to mp3. FLAC compression, by contrast, is akin to ZIP - a ZIP file retains 100% of the original data. An mp3 does not.

[Cebolla]

7 hours ago, tmtomh said:

MQA is lossy compression

MQA, be it in its undecoded state or in its decoded state, is always a PCM audio signal - therefore given that PCM is not compressed, it follows that MQA is not compressed.🙂

Not arguing that MQA isn't lossy, though!

[Cebolla]

8 hours ago, KingRex said:

How do they differ.  How does MQA get from 16 something to 24 something without decompressing.  There has to be a operation going on that uses computing resources.  

MQA only gets "from 16 something to 24 something" when you decode it. The computer player application doesn't have to decode MQA and use "computer resources" that way, as that job can be left to an external DAC that supports MQA decoding.  It most certainly is not "decompressing" MQA, as MQA is already PCM.

[Cebolla]

9 hours ago, KingRex said:

I have a single server usb connected to my dac.

Wow!

 

Not sure why you are not more concerned about Roon Core Server's already relatively large computer resource use as an audio file player in its own right, as well as maintaining its audio file library and other background activities 'affecting' HQPlayer on the same machine - when compared to its 'mere' extra resource use of it performing "Qobuz FLAC decompress"

[mansr]

MQA is a partially compressed format. In a typical 24-bit 48 kHz MQA stream, the upper 15 bits contain regular PCM data for frequencies up to 24 kHz. The low 8 bits are a compressed representation of the 24-48 kHz frequency band. The decoder decompresses this and joins the two bands to produce a 96 kHz audio stream with a resolution of approximately 16 bits. The compression must necessarily be lossy as, due to the fixed compression ratio, the number of possible inputs is greater than the number of possible outputs.

[Cebolla]

Ok I was being a bit mischievous - not being entirely happy with MQA being described as compressed, given its hybrid nature and dual personality. Partially compressed describes it aptly.

[firedog]

14 hours ago, KingRex said:

FLAC is lossless compression like MQA.  My setup is designed to do best up to 24/192 pcm.  No decompressing or upsampling.  Thats my setup.  If I purchase high resolution FLAC,  I need to use DBPoweramp to decompress and turn it onto WAV.  

 

Now I need to find out if I can put Qobuz offline library files onto my drive pre, decomptessed.  

MQA is lossy compression. 

A player like Roon can decompress flac before it sends it to your streamer. It can also turn any stream into 24/192 if your setup works better that way.

[tmtomh]

21 minutes ago, Cebolla said:

Ok I was being a bit mischievous - not being entirely happy with MQA being described as compressed, given its hybrid nature and dual personality. Partially compressed describes it aptly.

 

I don't care that much about the semantics, so if folks want to call it partially compressed that's fine. But my understanding is that a file is either compressed or it is not. If the data is rearranged and put into a different file format in order to reduce its size, then to my mind that's compression.

 

With MQA in particular, frequencies in the audible range are not compressed in terms of sample rate - an MQA file is 44.1 or 48kHz. But the bit-depth is impacted by the compression, with one or two of the first 16 bits used to store compressed/encoded higher sample-rate data for the unfold. To my mind, that makes MQA a compressed format. 

 

But again, I do not want to get into a semantics fight about whether it's partially compressed or just compressed. The point, IMHO, is that it's lossy, and it's proprietary.

[tmtomh]

4 hours ago, Cebolla said:

MQA, be it in its undecoded state or in its decoded state, is always a PCM audio signal - therefore given that PCM is not compressed, it follows that MQA is not compressed.🙂

Not arguing that MQA isn't lossy, though!

 

I do feel it's important to note that this is incorrect. mp3, AAC, FLAC, WAV, AIFF, and ALAC are PCM too, but they are compressed. Whether or not something is PCM has nothing to do with whether or not it's compressed. If you are using "PCM" to mean, "a PCM source in a file wrapper," that's fine - but then in that case you still cannot say that MQA is not compressed, because it is not just a file wrapper for PCM in the way that WAV and AIFF are, and it is not a lossy, non-destructive wrapper/encoding like FLAC and ALAC are.

[Cebolla]

26 minutes ago, tmtomh said:

If you are using "PCM" to mean, "a PCM source in a file wrapper," that's fine - but then in that case you still cannot say that MQA is not compressed, because it is not just a file wrapper for PCM in the way that WAV and AIFF are, and it is not a lossy, non-destructive wrapper/encoding like FLAC and ALAC are.

That was indeed what I was referring to - the point being MQA is the PCM audio signal source (albeit with something done to it) and therefore not a file wrapper full stop. So, MQA can be losslessly carried uncompressed by WAV & AIFF,  losslessly carried compressed by FLAC & ALAC and even carried lossily (God forbid) compressed by MP3 and the like.

[KingRex]

3 hours ago, Cebolla said:

Wow!

 

Not sure why you are not more concerned about Roon Core Server's already relatively large computer resource use as an audio file player in its own right, as well as maintaining its audio file library and other background activities 'affecting' HQPlayer on the same machine - when compared to its 'mere' extra resource use of it performing "Qobuz FLAC decompress"

Yes Roon is a resource drain.  That is why I try to  break up the processing and use the server in Roon Server mode and use another computer ethernet connected to operate Roon and manage the library.  Sonically its audible to operate this way. 

 

Sonically I know my machine is very good.  I put a Roon based endpoint in my setup and sonically it was tough to tell the difference.  As I said earlier, it was a little more clear and a touch more treble. Kind of like what I hear when I play FLAC but in reverse.  With FLAC its a little more hazy and a touch less extension.  

 

Some high resolution AIF files I have are very nice.  Other lack a little something.  Probably more to do with the recording.  Then again, the recording is king when it comes high performance playback as we all have system with high resolving capability and hear every change.

 

Thanks again for all the feedback.  

 

FYI, I use the Mojo Audio digital setup.  The owner Ben, keeping with the times is putting a ethernet rendering card in his upcoming DAC.  He too gets processing noise kills sound quality and its best to break up the duties.  That is partly why I have not bought an endpoint at this time.  I assume a built in renderer with an I2S connection will be superior to USB.  That is the way MSB and Esoteric are doing it.  Same with Rockna.  Rockna differs as they still uses 2 boxes and a cable.