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Comment by _Marak_ | Hacker News Reader

Based on the comments here, it seems this tool is powered by youtube-dl.

youtube-dl is a great tool ( supports multiple websites outside of youtube as well )

The problem is...if you use youtube-dl to rip songs from youtube you are going to be stuck with a not so great quality bitrate.

Based on some quick research, it looks like the top quality audio bitrate you can get currently get from youtube is 126.886 kbps. That's going to really reduce the quality of any song you rip from the site. Most songs are digitally released at 320kbps these days. CD quality is 192kbsp.

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Maybe I'm biased because for the music I listen to, the quality makes little difference, but if you want the high bitrate, shouldn't you expect to actually pay for the song?

You see the same sorts of comments on torrent sites, people saying like "this is not actual 320kpbs audio, I analyzed it with [whatever] and it's clearly 128kbps reencoded as 320kbps", which I guess is fine as a PSA, but it does imply a really high expectation from people illegally uploading music for free to be illegally downloaded for free.

This has been an age old question since Mp3s were created. However, I'm going to disagree with you there on saying that CD quality = 192kb. I've heard 192kb files and they sound like complete garbage. If you're looking for true "CD quality" that would be LPCM 44100 Hz 16 bits stereo for a bitrate of 1411 kbps.

I've heard this before elsewhere and the response then was that the person was confusing kilobits with kilobytes. 1411kbps/8bits/byte = 176.375Kbps. The closest you can get to that is 192Kbps. There's a big difference there.

MP3 bitrates are conventionally given in kilobits per second, not bytes.

> I've heard 192kb files and they sound like complete garbage.

I'm curious, did you blind test yourself? I blind tested a friend of mine who kept saying so, and he did barely better than random.

It's very easy to tell the difference between 192kbps and FLAC if you have a decent subwoofer and the song ever goes below 30hz. On run-of-the-mill speakers and earbuds, probably not.

It's extremely rare for music to contain anything below 30Hz. Even below 40Hz is rare. The only place you're likely to find such low frequencies is sound effects in movie soundtracks.

I'm sorry, I pulled that number out of my ass.

I should have said 'if the frequency goes sufficiently low'.

Unless you are into Bassnectar and the like... ;)

Interestingly, a lot of "bass heavy" music focuses on frequencies around 50Hz, not the really deep sub-bass. This makes sense when you consider human hearing. Those higher frequencies sound much louder to us, and they're still low enough to get the tactile feeling.

It really does depend on the file. However, if we're talking about most 192KB music files, they tend to sound "tinny" or shallow. There's not a lot of depth to the sound as compared to quality you would get from a CD.

From Wikipedia's page on Compact Disc Digital Audio:

Each audio sample is a signed 16-bit two's complement integer, with sample values ranging from −32768 to +32767. The source audio data is divided into frames, containing twelve samples each (six left and right samples, alternating), for a total of 192 bits (24 bytes) of audio data per frame.

https://en.wikipedia.org/wiki/Compact_Disc_Digital_Audio#Dat...

That has nothing to do with the bitrate -- the fact that you're getting a different unit on your 192 should be in an indication (bits or bits/frame, as opposed to kilobits/second).

CDs store audio as 16 bit samples, with 44100 samples per second. This gives a bitrate of 16 bits * 44100 Hz = 705600 bits/second (705.6 Kbps). This is per channel, so the total bitrate of the format is 1411.2 kbps, as stated (modulo rounding) by the GP.

EDIT: in fact, the article you link specifically says (a couple sections further down) that the bitrate is 1411.2 kbps.

This means CDs should have ~800MB of usable space. Why only 700MB?

    705600 * 2 = 1411200              # bits/s for stereo channel
    80 * 60 = 4800                    # seconds in 80 minutes
    1411200 * 4800 = 6773760000       # bits in a 80 minutes CD
    6773760000 / 8 / 1024 /1024 = 807 # In MB

Error correction.

While a 'raw' redbook CD can hold ~850 MB, it is standard to included error correction codes so that a slightly scratched CD can still work.

CD quality is not 192 kbps. 320 is the maximum bit rate that a MP3 can provide, and is the standard for the other lossy formats (such as AAC). These formats compress audio by cutting out difficult to hear frequencies. By contrast, CD quality is considered lossless, because it represents the entire frequency of the sound wave. 320 kbps is less data than a CD. Whether the jump from a good quality MP3 to a lossless format gives you a higher quality listening experience is up for debate, but 126 kbps is definitely terrible.

This website can help you compare the bit rates and see if you can hear the difference. http://www.npr.org/sections/therecord/2015/06/02/411473508/h...

Yes, YouTube's audio quality is noticeable worse than a 320kbps MP3, for me the difference makes the music less enjoyable.

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