Audiophile questions: CDs, FLACs, PC optical drives

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PostmanPot

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Hi all

Got a few questions:

1) FLAC music one may find on the net can be like 250MB per album (varies). I would imagine there is surely some loss of quality here, seeing as a ±60min CD should be about 700MB?

2) If storage isn't an issue, would one be able to rip a CD at its pure 700MB quality without any detail loss as FLAC? Would other formats need to be sought? Or will there inherently be loss when converting from CD to digital?

3) If so, what are your common PC optical drives like for CD playback? I've got a Sony-Optiarc.

Thanks.
 
PostmanPot said:
Hi all

Got a few questions:

1) FLAC music one may find on the net can be like 250MB per album (varies). I would imagine there is surely some loss of quality here, seeing as a ±60min CD should be about 700MB?

2) If storage isn't an issue, would one be able to rip a CD at its pure 700MB quality without any detail loss as FLAC? Would other formats need to be sought? Or will there inherently be loss when converting from CD to digital?

3) If so, what are your common PC optical drives like for CD playback? I've got a Sony-Optiarc.

Thanks.
Click to expand...

Why are you assuming that WAV files are the only lossless form of presenting audio data?

Besides, if this is really a concern, then 16 bit 44 KHz sources (CDs) are not the best choice in first place.
 
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I'm hot and bothered, excuse the sarcasm

FLAC- Free LOSSLESS Audio Codec

LOSSLESS being no LOSS

The reason it isn't 700MB is twofold: 1. No cd is full 72min 2. Compression similar to .zip is done, which does not affect the sound at all.

If you want it in the exact same format, but lose all tagging, that is what .wav is. wma lossless, apple losless or flac can at least be tagged.

Simply, if you can hear a difference a. you must have an amazing set up b. you must have a pathetic PC that it can't hold a wav file in RAM, which is what happens with lossless codecs, decompressed and converted to analogue.
 
copacetic said:
Why are you assuming that WAV files are the only lossless form of presenting audio data?

Besides, if this is really a concern, then 16 bit 44 KHz sources (CDa) are not the best choice in first place.
Click to expand...

I did not realise the 700MB equated to .wav form?
 
Mike43110 said:
I'm hot and bothered, excuse the sarcasm

FLAC- Free LOSSLESS Audio Codec

LOSSLESS being no LOSS

The reason it isn't 700MB is twofold: 1. No cd is full 72min 2. Compression similar to .zip is done, which does not affect the sound at all.

If you want it in the exact same format, but lose all tagging, that is what .wav is. wma lossless, apple losless or flac can at least be tagged.

Simply, if you can hear a difference a. you must have an amazing set up b. you must have a pathetic PC that it can't hold a wav file in RAM, which is what happens with lossless codecs, decompressed and converted to analogue.
Click to expand...

Setup is Asus Xonar Essence STX amplified sound card with Sennheiser HD 650. 8GB RAM. Rest of PC is fine. Not sure whether that is amazing enough, because I'm hearing distortion. I also heard it with my HD 595s. So I blame the certain FLAC files. I would imagine there are different ways of ripping to achieve different file sizes? In which case perhaps that's what the problem is. Unless I'm wrong?
 
Yup, FLAC should be fine as far as audio quality goes. There are better media than CD out there providing better sound quality. This is where SACD comes in. If memory serves, BR is also capable of carrying quite a bit better audio quality than CD, but I stand to be corrected on that one.
I'm afraid I'm not that well versed with optical drive technology, so I can't comment on the sound quality being delivered by it. I would think that it shouldn't make a difference seeing as the data is digital.
 
PostmanPot said:
Setup is Asus Xonar Essence STX amplified sound card with Sennheiser HD 650. 8GB RAM. Rest of PC is fine. Not sure whether that is amazing enough, because I'm hearing distortion. I also heard it with my HD 595s. So I blame the certain FLAC files. I would imagine there are different ways of ripping to achieve different file sizes? In which case perhaps that's what the problem is. Unless I'm wrong?
Click to expand...

Nah you're spot on. As with video, there are different methods of encoding. All WAV files aren't even equal either. Completely raw WAVs generated when recording in studio get into the hundreds of MB per track, if not GBs. The trick is to get your hands on these really high quality tracks, which is easier said than done.

Oh, your distortion may be due to your soundcard's powersupply or how its DAC functions. No point in having 24-bit audio if your output device's DAC only supports 12-bit, as an example. Your sound card's firmware may also affect the decoding of the audio and not work perfectly due to the audio format.
 
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Messugga said:
Nah you're spot on. As with video, there are different methods of encoding. All WAV files aren't even equal either. Completely raw WAVs generated when recording in studio get into the hundreds of MB per track, if not GBs. The trick is to get your hands on these really high quality tracks, which is easier said than done.

Oh, your distortion may be due to your soundcard's powersupply or how its DAC functions. No point in having 24-bit audio if your output device's DAC only supports 12-bit, as an example. Your sound card's firmware may also affect the decoding of the audio and not work perfectly due to the audio format.
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Doubt it's my sound card. As I said, specific tracks/albums only i.e notice slight distortion in the left channel or such, slight distortion of vocals... Then on another album from the same artist, no such thing. I can only put it down to poorly-ripped FLACs.

So my question, would I be able to achieve maximum CD fidelity if ripped to FLAC at its highest quality/size settings?
 
PostmanPot said:
Doubt it's my sound card. As I said, specific tracks/albums only i.e notice slight distortion in the left channel or such, slight distortion of vocals... Then on another album from the same artist, no such thing. I can only put it down to poorly-ripped FLACs.

So my question, would I be able to achieve maximum CD fidelity if ripped to FLAC at its highest quality/size settings?
Click to expand...

FLAC (Free Lossless Audio Codec) is a codec (compressor-decompressor) which allows digital audio to be losslessly compressed such that file size is reduced without any information being lost. Digital audio compressed by FLAC's algorithm can typically be reduced to 50–60% of its original size, and decompressed into an identical copy of the original audio data.
Click to expand...

It will be identical, bit for bit.
 
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Basically all tracks (or rather albums) are not created equally which is what it boils down to at the end of the day and why you are hearing distortions where you wouldn't expect.

Have to admit though that on a very high end head-fi setup I couldn't really tell the difference between a FLAC and a 320kps MP3 file so I ended up sticking to MP3 (7-8mb vs 27-30mb does add up after while :))
 
Deezil said:
Basically all tracks (or rather albums) are not created equally which is what it boils down to at the end of the day and why you are hearing distortions where you wouldn't expect.

Have to admit though that on a very high end head-fi setup I couldn't really tell the difference between a FLAC and a 320kps MP3 file so I ended up sticking to MP3 (7-8mb vs 27-30mb does add up after while :))
Click to expand...

I struggle to tell @ 320 myself, but the main point here is that the 1s and 0s streaming off the CD will be IDENTICAL to those streaming off a FLAC rip of the same CD.
 
copacetic said:
It will be identical, bit for bit.
Click to expand...

In my example above, I cannot understand how an artist/band could release a CD with distortion in the left channel, or distortion of high vocals. Surely not? Surely therefore the "ripper" (or their settings) is to blame.

I understand that an identical copy could be ripped to 50 - 60% of the original size. Further, my understanding that that could have varying success, depsnding on the ripper.

Yes?
 
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PostmanPot said:
In my example above, I cannot understand how an artist/band could release a CD with distortion in the left channel, or distortion of high vocals. Surely not? Surely therefore the "ripper" (or their settings) is to blame.

I understand that an identical copy could be ripped to 50 - 60% of the original size. Further, my understanding that that could have varying success, depsnding on the ripper.

Yes?
Click to expand...

Look, I don't want to argue with you. The point is that FLAC is a lossless format, end of story. It is identical to the CD, bit for bit.

Check here, this is my DAW's render dialogue:

tWvav.png


As you can see, the FLAC menu is in terms of encoding speed, not quality, as there are no quality choices to be made, as the encoding is identical to the original source.

There are many other processes that could have been run on those files, such as maximising the audio level, which would then more likely explain any distortion you get. But if you yourself rip something from a CD to FLAC without doing anything else to the file, it will be digitally identical.
 
A wav file is simply a container for PCM (Pulse-code modulation) data. The size of PCM data depends on three things:

- Sample rate (44.1 kHz for CD)
- Bits per sample (16 for CD)
- Number of channels (2 for CD)

So, a 80min CD will contain 44100 * (16 / 8) * 2 * (80 * 60) = 846 720 000 bytes (807.5 mB) of PCM data. The Wav file header adds a couple of kB to that.

One of the reasons that FLAC can make lossless copies that are half the size of the raw data is that there's usually a lot of duplication between the channels.
 
copacetic said:
But if you yourself rip something from a CD to FLAC without doing anything else to the file, it will be digitally identical.
Click to expand...

That's what I wanted to know, because I assume something else has been done resulting in distortion. If I do it myself, I can be assured of an identical copy.
 
Rkootknir said:
A wav file is simply a container for PCM (Pulse-code modulation) data. The size of PCM data depends on three things:

- Sample rate (44.1 kHz for CD)
- Bits per sample (16 for CD)
- Number of channels (2 for CD)

So, a 80min CD will contain 44100 * (16 / 8) * 2 * (80 * 60) = 846 720 000 bytes (807.5 mB) of PCM data. The Wav file header adds a couple of kB to that.

One of the reasons that FLAC can make lossless copies that are half the size of the raw data is that there's usually a lot of duplication between the channels.
Click to expand...

What reasons would lead to there, for example, being distortion in the left channel or distortion of high vocals on one particular FLAC whose source I'm unsure of?

What would you put it down to... Poor production/mastering, or "other processes" having been run on those files by the ripper?

Who is to blame?!
 
Easiest would be to put a scope on the output and look in detail at whether there is distortion. It could be many different things, from the sound card, your powersupply, to your headphones. It could be an unhealthy cap that doesn't filter noise properly at certain frequencies. It could be a resistor that's not balancing things out perfectly due to variance in its value. It could be the sound card's firmware.
 
PostmanPot said:
That's what I wanted to know, because I assume something else has been done resulting in distortion. If I do it myself, I can be assured of an identical copy.
Click to expand...
Are you sure the distortion isn't in the original? Most of the waveforms in sound recordings these days are compressed to the bleeding edge. Combined with some bad sound engineering this leads to clipping on CDs.

Some of the worst examples of this: Metallica's Death Magnetic and RHCP's Californication. I can't listen to either of these due to the constant clipping.
 
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