Lossless mp3 (44.1 KHz 24bit 2ch 244kbps) vs. FLAC

My question is about the quality evaluation of the music source in the Signal Path analyser in the Roon client.
I have CDs ripped in “Losess MP3” format (44.1 KHz 24bit 2ch 244kbps) which is evaluated as inferior quality compared to FLAC in 44.1KHz 16bit 2ch.
Why is that?
Any thoughts on Losless MP3?


What is “Lossless MP3” and how do you suppose you get 24bits from a 16bit CD?

MP3 is 16 bit not 24.
FLAC is lossless, MP3 is lossy.
Google MP3 Vs FLAC or similar.

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Do not quite understand this. MP3 can be ripped in different bit rates. Very low 96kbs to 128, 160, 192 and then topping out at 320kbs. You can also rip to MP3 with a technique called a Variable Bit rate which as it states the bit rate varies through out the song however this does not make it lossless.

You are referring to a bit rate of 244kbs which seems to me it is a variable bit rip. Depending on which program that you using to read this file, that rate could change depending on where a particular program grabs the sample to evaluate. I have seen a sample rate in variable bit rate in the high 700kbs but again this does not make it lossless.

I am not familiar with any program can rip a MP3 into 24bit.


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If your are going to RIP, do it once, do it lossless and FLAC is the way to go.


The benefit of this that your rip is future proofed for any other codec that might arise in the future.


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Agreed, I do not believe lossless MP3 exists.


Lossless MP3 doesn’t exist. I’m no engineer or expert here - but as it was explained to me (on here) MP3 encoding does not have a fixed bit depth, so - regardless of what was input - an MP3 can be decoded / rendered as 16-bit or 24-bit (or something else presumably). Roon started rendering MP3 and other lossy formats as 24-bit a couple of updates ago - with audibly excellent results IMO. So, if you have a stash of MP3s Roon is a great way to play them - but lossless is always the way to go if you can get it (whether ripping or downloading).


I wonder if the term “lossless mp3” is used by your ripping/encoding software to designate high-bitrate mp3? There is no such thing as actually lossless mp3 - information is lost when encoding to mp3. However, I could see someone using the term “lossless” to imply that a truly lossless format is indistinguishable from a high-bitrate mp3. The implication is incorrect, at least to my ears, but I could see such casuistry coming from a marketing department or someone with an axe to grind.

I believe the formula to get kbps is something like:
Bit depth (Levels per sample) * samples per second *2(for stereo).

So CD quality is 16/44.1 or 16*44.1(*2 for stereo) kbps. = 1411.2kbps

I always wondered why CD quality is called lossless - if the recording was made in, say, 24/96 (4,608kbps) and then gets pared down to CD size, then surely it is, in fact, lossy not matter which format you use to rip the CD.

By the same token, if some terrible recording studio recorded in 8/15.25 (lol) then a digital format of that snip recording at 244kbps would be lossless.

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That depends on how you compress and decompress it. All the musical data will be in a CD file, it’s the effect of digital filters on the signal that cause damage. So we have upsampling with apodizing filters and MQA to try to minimise this.

10 posts were split to a new topic: MQA is the new MP3

Hello all,
First of all. Thanks for all the great replies and comments. Super community spirit.

You are all right; MPS is not lossless but lossy. I used the term “lossless” loosely. My apologies.

In any case, I ripped the MP3s at highest quality settings using the LAME encoder. The parameters I listed above are what the ROON Signal Path analyser shows me for my MP3 files : 44.1 KHz / 24 bit / 2 ch / 244 kbps.

And that’s a little bit my question: How come the Signal Path analyser shows the MP3 files with those parameters ?

To test the quality, I ripped a couple albums to FLAC also using the LAME encoder, but I hear no difference in my setup: Roon streaming to an AudioQuest Dragofly Red DAC connected to a vintage Technics SU3400 integrated power amp (https://audio-database.com/TechnicsPanasonic/amp/su-3400-e.html) driving a pair of FOCAL Chorus 926 speakers (https://www.focal.com/en/home-audio/high-fidelity-speakers/aria-900/floorstanding-speakers/aria-926). But at my age (retired) that’s probably normal.

Everyone - Thanks for all your reactions.

Interesting - can you show an image of your signal path, please?
Are you upsampling with DSP by any chance?

Roon processes the MP3 file into those parameters. What you’re seeing is Roon’s decompression of the lossy MP3. Sounds pretty good to me.

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Yep Bill is correct. All lossy codecs such as MP3, oggvorbis or AAC will get upsampled to 44.1/24 in Roon so it can handle them better so that’s what you are seeing. If you rip flac lossless then you will notice a difference in sq compared to these regardless of upsampling g. Garbage in Garbage out is always the rule.

Roon does not “upsample” MP3 and AAC to 24 bit. It decodes those lossy files to 24 bit.



What’s exactly the difference?

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When something is lost, it’s is lost forever. No matter how much you upsample it.

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Check out this thread: A way to decode lossy files to >16 bits per sample [Delivered in build 333]

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