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  1. #1

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    Default Ripping Redbook CD at bitrate 320

    I've been ripping RBCD using MS Media Player using a bitrate of 320, and then burn it back to a CD, to make a replica/copy. What I find interesting is, I can't seem to be able to notice ANY difference with the original source. From slam, micro dynamic, instrument details, etc, no difference. So, in my opinion, the bitrate at 320 seems to be the optimal bitrate.

    Thoughts, opinions, and experiences?
    I am sorry, I have no opinion on the matter. I am sure you do. So, don't mind me, I just want to talk audio and pie.

  2. #2

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    320's really high, i use a little less and am quite happy... i think people avoid compression out of principle more than anything else...
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    If you are making CD copies, why compress at all? Rip it uncompressed as a .wav with EAC and burn that back to CD.

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    Quote Originally Posted by anonymouse
    If you are making CD copies, why compress at all? Rip it uncompressed as a .wav with EAC and burn that back to CD.
    Because you can fit 4-5 original CD's into a single 320 CD.

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    what type of music are you doing this for?

    i have not done experiments like this but when i have heard differences between compressed and uncompressed it is usually in very wide-range music (classical) and not so much in rock/pop music.

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    Default cd copies

    Hi,
    I find that so many of the players I would play the disc on are not able to play anything but wav files. So I have used wav files for all recordings. The car, the work, and the portable cd players I use all play redbook only so the debate about the difference in quality isnt an issue because they wont make any sound unless it is a wav file.
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  7. #7

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    I use clone CD and choose the burn on the Fly. I have never noticed any problems

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    It may not be night and day, but I can definitely hear a difference on my wma files ripped at 320 KBps - even in my crappy car system.

    I'm surprised that you can't hear a difference between the original and the compressed, even though it's a small difference at 320 KBps.

    Having said that, I rip all my stuff at 320 into wma and that works fine for the car. Even though I can hear a difference, it's not much and not enough to offset the convenience of having most of my music collection fit inside a 320 cd case. I don't do critical listening in the car, so it works fine for me.

    FWIW, these discs don't get play time in the house anywhere...
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  9. #9

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    Quote Originally Posted by PolkThug
    Because you can fit 4-5 original CD's into a single 320 CD.
    I thought when you actually burnt the CD it was just uncompressing the MP3 and putting it on the disc. So, regardless of the bitrate you choose, the same amount of music fits on the CD (X number of uncompressed bytes). Now, if you're making an MP3 disc, that's a different story. Then compression takes a role. Maybe that's what needs clarification. Are we talking MP3 discs or standard copies?
    I too have used 320 bitrate, but I'm not sure I could hear a difference with with 256. Maybe 320 for me was more a peace-of-mind thing. But, if you're keeping these MP3's on your PC, it'll obviously use more space.

    Bikerboy,
    I wonder if your MP3 issue has something to do with a setting within the software that treats WAV's different than MP3's when burning. Things like "closing the disc" and "adding a 2 second gap" and "burn at once" and stuff like that can help or hamper a CDP. I only wonder because I thought burning software just uncompressed the MP3 (like to a WAV) anyway and then used that temp data to actually burn the CD.
    I don't know, just some thoughts.
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    I copy original cds onto my hd using Windows Media. It burns onto another cd @ 128 kbps. I have noticed no difference when played on my Rotel CD player.

    If it's a poor quality original it will be a poor quality copy.
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  11. #11

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    Quote Originally Posted by cfrizz
    If it's a poor quality original it will be a poor quality copy.
    ;) :D

    Great point

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    Great discussions! I guess I am not the only one wondering about this.

    Polkmaniac, I tried to hear the difference, but I can't. I have a pretty decent setup on two channels and HT, but still no obvious difference when I compare it with the originial CD, other than a sense of "I think I hear a slight..." placebo effect, perhaps.

    Btw, I ripped-to-HD-and-burned-to-CD two-step process since I also synch it with my iPod (via iTunes). Most of you know I am a Jazz freak, so I make copy of those albums that I really like, to play on my bedroom (two channels) system, for convenience reason.

    Is there a higher bit-rate ripping beyond 320?
    I am sorry, I have no opinion on the matter. I am sure you do. So, don't mind me, I just want to talk audio and pie.

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    I've never seen anything beyond 320 for MP3, but that doesn't mean there isn't. Not sure.
    Seems like you could just go with WAV format which is uncompressed if you wanted really high bitrate.
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  14. #14

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    I'm pretty sure 320 kbps is the max birate for MP3s...
    I have heard a noticeable difference when mp3s are ripped below 112kbps, especially on the high end spectrum... anything above 112kbps (128, 256, 320) sounds the same to me (maybe my ears are F****d up)
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    I actually did an AB comparison between 192k mp3's and the original. I personally could hear a difference in the high end and the depth of the music. This was with Norah Jones and her voice changed quite a bit. This was using Klipsch RF7 speakers off a Denon 3806 and a 3910 as the source. We actually had two players and just changed the input on the receiver so it was a fast A-B switch. Not like we took the disk out then put in the other and forgot what the first sounded like.
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    Kind of off subject, but isn't the bitrate of .wav files 1411kbps?
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  17. #17

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    yep:
    44,100 samples * 16 bit * 2 channels = 1411.2 kbps

  18. #18

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    Try VBR (variable bitrate) as well, you can set median at 320 but enable VBR and save yourself some decent file size.

    I tend to use 128 VBR with LAME most of the time, it's better than plain 128 without being too much larger. You get a nicer high end than straight bitrate and the weirdness up high is reduced.
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    To each their own but going from 1411 kbps to 320 kbps should be noticeable. I admit if you take a great recording in .wav or.cda which is standard and convert it using the likes of the Freuhauffer algorythm at 320 kbps, it can sound pretty good. But, IMO on a high resolution system you'll notice some differences. There seems to be a tad more glare, less definition and natural decay on cymbals and the lower midrange can sound hollow and thin and the bottom end just rolls off rather than extends. This has been my experience with recordings I am very very familiar with. Personally when I'm making Mp3's for portables 320 is the minimum for me.

    All MP3's are not evil, but they should never be used in place of the real thing in a reference system. You can get away with using them in a portable player, boombox type players, car environment, low quality home gear (HTiB), compliation music for a party or sampling music, etc. Never on a high quality home system or in place of the real thing, like purchasing them thru an on-line music seller.

    YMMV

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    Use a variable bit rate at 192 then you are using more or less bits as required by the music or a particular passage. It optimizes sound and size. More bits when necessary and fewere bits if not necessary. No sense in encoding at 320 for a chilled out love song. There wouldn't be enough info to bother encoding that high so you are just wasting space.
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    Quote Originally Posted by phipiper10
    Use a variable bit rate at 192 then you are using more or less bits as required by the music or a particular passage. It optimizes sound and size. More bits when necessary and fewere bits if not necessary. No sense in encoding at 320 for a chilled out love song. There wouldn't be enough info to bother encoding that high so you are just wasting space.
    Except the fact that 70% of the music is missing even at the highest bit rate. That last sentence is simply not true and is a gross simplification. Compression in the form of Mp3's is not a good thing, passable for certain situations as I mentioned in my previous post. Let's not get all rosy and happy and start making statements like the last sentence. This is how misinformation is perpetuated and then taken as fact.

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    The intent WAS to oversimplify. I'm not advocating mp3s over CDs. I've had literally thousands of CDS in shn or flac formats to avoid mp3s used check sums etc to insure quality. MP3 is practically profanity in the circles I've been in before. I'm just saying that at 192 VBR for people who do use mp3s very few people will tell the difference. It would be crazy to play at 128 on a true audiophile system for the purposes of critical listening. Hopefully like you said if you are using mp3 it's in your car or while working out etc. With VBR rate you are getting more bang for your buck than straight CBR at the same rate. That was really my only point.

    There may be 70% less information but not necessarily 70% less music to the ears. Nobody would use mp3s if 70% of the music was missing - So if 75%of the music was missing for example the Beatles would sound like Ringo doing a drum solo?. Not really.

    No flames intended.
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    Quote Originally Posted by phipiper10
    The intent WAS to oversimplify. I'm not advocating mp3s over CDs. I've had literally thousands of CDS in shn or flac formats to avoid mp3s used check sums etc to insure quality. MP3 is practically profanity in the circles I've been in before. I'm just saying that at 192 VBR for people who do use mp3s very few people will tell the difference. It would be crazy to play at 128 on a true audiophile system for the purposes of critical listening. Hopefully like you said if you are using mp3 it's in your car or while working out etc. With VBR rate you are getting more bang for your buck than straight CBR at the same rate. That was really my only point.

    There may be 70% less information but not necessarily 70% less music to the ears. Nobody would use mp3s if 70% of the music was missing - So if 75%of the music was missing for example the Beatles would sound like Ringo doing a drum solo?. Not really.

    No flames intended.
    Got it.....I try to be a one person crusade against Mp3's being used in place of regular audio files. Just setting the record straight and wasn't meaning to come down on your post. :)

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  24. #24
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    I am not armed with that much technical information in regards to bit's, and the information (and lack thereof) in different sizes, compression values, etc... All I have is experience listening and trying a lot of different equipment, etc...

    I'll keep it simple. There was a time when I felt the difference between a 320 kbps mp3 and the original .wav was more/less imaginary. I've spent some time training myself on what to listen for. Of course, it's also much easier when you get higher resolution electronics! :p Well, you all know where I'm going with this one.

    Most of the time's, the difference between a good 320kbps rip and the original .wav is noticable. I usually find the differences to be a few steps above what most would probably call "subtle". Definately noticable, enough to where you can acknowledge you have made a few sacrifices to get that file size down, but not enough to where you cannot enjoy the said track.

    Now what really intrigues me is a good rip in a proven reliable format, ala flac. I honestly cannot distinguish the difference between the original and these rips.

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    A 320 MP3 CD with 100 songs on it is great to pop in your home system on random play!

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    Zero, have you experimented with .ogg files any? They're supposed to be a great alternative to MP3, too.
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  27. #27
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    Yep. Good alternative. Not that much support and popularity with .ogg. Its become more mainstream with PC gaming industry though.

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    I went back and fourth on this same matter for a long time not to long ago when i was trying to decide what format to rip all of my cd's to to put on my car computer. I tried everything from 128cbr 192vbr 320cbr 320vbr flac ogg wav etc etc. For what i could hear, i heard absolutley no difference between the first set of tests (the 128 - 256 in cbr and vbr) The second half of the test i think the differences were just in my head but i did think i herad som differences (i really need to do this one blind with a buddy so i know if i was actually hearing differences or not)

    I tried flac and did not like it, either i was doing something wrong or that is how a flac sounds. Flac files sounded worse than the 128cbr counterpart, it actually soundd pretty hollow and even had some distortion on the high end??

    For simple ease of the rip and confidence in the fact that i did lose any quality i have started to rip all of my cd's as wav files onto my car computers harddrive. This was alot easier than continueing to debate with myself about wich compression format was better.

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    Quote Originally Posted by BrentMcGhee
    I tried flac and did not like it, either i was doing something wrong or that is how a flac sounds. Flac files sounded worse than the 128cbr counterpart, it actually soundd pretty hollow and even had some distortion on the high end??

    For simple ease of the rip and confidence in the fact that i did lose any quality i have started to rip all of my cd's as wav files onto my car computers harddrive. This was alot easier than continueing to debate with myself about wich compression format was better.
    wow brent, i am really suprised by this. i can definately see why there would be differences between the different mp3/ogg formats since they are all in some way changing the output waveform but with flac there really is no difference at all (technically) between it and .wav. i guess i would lean towards somehing going wrong with either the encoding or decoding that you are using (or maybe the player?). the idea with flac and shn is that the original PCM bitstream is recoverable from the file so that whatever is going into your DAC is exactly the same set of bits that you would get if you were playing back a wav file.

    now not that i am going to tell you that you are not hearing differences, just that i see it being highly unlikely that it is the acutal file format that is causing the differences.

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    Talking Warning Long Post-But interesting

    Quote Originally Posted by BrentMcGhee
    I tried flac and did not like it, either i was doing something wrong or that is how a flac sounds. Flac files sounded worse than the 128cbr counterpart, it actually soundd pretty hollow and even had some distortion on the high end??
    Mp3's are subtly different and not everyone can hear much of a difference or cares to hear much of a difference. My only point in discussing Mp3's is that people experiment for themselves and not make blanket statements about them being the same as the original audio file. That's when I fly off the handle many times against Mp3's

    You must have had some issue with your FLAC files as those should have sounded the best. As you know it's a lossless format and for the most part creates the original wave exactly, atleast beyond what myself and most who use it can hear or even measure for that matter. Plus a car environment is not condusive for great fidelity.

    FWIW,

    MP3 is a compression format. It provides a representation of pulse-code modulation-encoded (PCM) audio data in a much smaller size by discarding portions that are considered less important to human hearing (similar to JPEG, a lossy compression for images).

    A number of techniques are employed in MP3 to determine which portions of the audio can be discarded, including psychoacoustics. MP3 audio can be compressed with different bit rates, providing a range of tradeoffs between data size and sound quality.

    ***the highlighted passage is why mp3's should never be used to replace the real thing, psychoacoustic's is an integral part of great sounding music***

    Because MP3 is a lossy format, it is able to provide a number of different options for its "bit rate"—that is, the number of bits of encoded data that are used to represent each second of audio. Typically rates chosen are between 128 and 320 kilobit per second. By contrast, uncompressed audio as stored on a compact disc has a bit rate of 1411.2 kbit/s.

    MP3 files encoded with a lower bit rate will generally play back at a lower quality. With too low a bit rate, "compression artifacts" (i.e., sounds that were not present in the original recording) may appear in the reproduction. A good demonstration of compression artifacts is provided by the sound of applause: it is hard to compress because it is random, therefore the failings of the encoder are more obvious, and are audible as ringing.

    As well as the bit rate of the encoded file, the quality of MP3 files depend on the quality of the encoder and the difficulty of the signal being encoded. For average signals with good encoders, many listeners accept the MP3 bit rate of 128 kbit/s and the CD sampling rate of 44.1khz as near enough to compact disc quality for them, providing a compression ratio of approximately 11:1. MP3s properly compressed at this ratio can achieve sound quality superior to that of FM radio and cassette tape, primarily due to the limited bandwidth, SNR, and other limitations of these analog media. However, listening tests show that with a bit of practice many listeners can reliably distinguish 128 kbit/s MP3s from CD originals[citation needed]; in many cases reaching the point where they consider the MP3 audio to be of unacceptably low quality. Yet other listeners, and the same listeners in other environments (such as in a noisy moving vehicle or at a party) will consider the quality acceptable. Obviously, imperfections in an MP3 encode will be much less apparent on low-end computer speakers than on a good stereo system connected to a computer or -- especially -- using high-quality headphones.

    Good encoders produce acceptable quality at 128 to 160 Kibit/s and near-transparency at 160 to 192 kbit/s, while low quality encoders may never reach transparency, not even at 320 kbit/s. It is therefore misleading to speak of 128 kbit/s or 192 kbit/s quality, except in the context of a particular encoder or of the best available encoders. A 128 kbit/s MP3 produced by a good encoder might sound better than a 192 kbit/s MP3 file produced by a bad encoder.

    It is important to note that quality of an audio signal is subjective. A given bit rate suffices for some listeners but not for others. Individual acoustic perception may vary, so it is not evident that a certain psychoacoustic model can give satisfactory results for everyone. Merely changing the conditions of listening, such as the audio playing system or environment, can expose unwanted distortions caused by lossy compression. The numbers given above are rough guidelines that work for many people, but in the field of lossy audio compression the only true measure of the quality of a compression process is to listen to the results.

    If your aim is to archive sound files with no loss of quality (or work on the sound files in a studio for example), then you should use Lossless compression algorithms, currently capable of compressing 16-bit PCM audio to 38% while leaving the audio identical to the original, such as Lossless Audio LA, Apple Lossless, TTA, FLAC, Windows Media Audio 9 Lossless (wma) and Monkey's Audio (among others). Lossless formats are strongly preferred for material that will be edited, mixed, or otherwise processed because the perceptual assumptions made by lossy encoders may not hold true after processing. The losses produced by multiple stages of coding may also compound each other, becoming more evident when the signal is reencoded after processing. Lossless formats produce the best possible result, at the expense of a lower compression ratio.

    Some simple editing operations, such as cutting sections of audio, may be performed directly on the encoded MP3 data without necessitating reencoding. For these operations, the concerns mentioned above are not necessarily relevant, as long as appropriate software (such as mp3DirectCut and MP3Gain) is used to prevent extra decoding-encoding steps.

    There are several limitations inherent to the MP3 format that cannot be overcome by using a better encoder.

    Newer audio compression formats such as Vorbis and AAC no longer have these limitations.

    In technical terms, MP3 is limited in the following ways:

    * Bitrate is limited to a maximum of 320 kbit/s
    * Time resolution can be too low for highly transient signals
    * No scale factor band for frequencies above 15.5/15.8 kHz
    * Joint stereo is done on a frame-to-frame basis
    * Encoder/decoder overall delay is not defined, which means lack of official provision for gapless playback

    Nevertheless, a well-tuned MP3 encoder can perform competitively even with these restrictions.


    FLAC is distinguished from general lossless algorithms, such as ZIP and gzip, in that it is specifically designed for the efficient packing of audio data: while ZIP may compress a CD-quality audio file by ten to twenty percent, FLAC achieves compression rates of thirty to fifty percent.

    While lossy codecs can achieve ratios of eighty percent or more, they do this by discarding data from the original stream. FLAC uses linear prediction to convert the audio samples to a series of small, uncorrelated numbers (known as the residual), which are stored efficiently using Golomb-Rice coding. It also uses run-length encoding for blocks of identical samples, such as silent passages. The technical strengths of FLAC compared to other lossless codecs lie in its ability to be streamed and in a fast decode time, which is independent of compression level.

    FLAC has become the preferred lossless format for trading live music online. Monkey's Audio and Shorten are frequently used as well, although FLAC files are smaller than Shorten files.

    FLAC is also a popular archive format for owners of CDs and other media who wish to preserve their valuable audio collections. If the original media is lost, damaged, or worn out, a FLAC copy of the audio tracks ensures that an exact duplicate of the original data can be recovered at any time, a restoration impossible from a lossy archive (e.g., MP3) of the same data. The optional creation of a CUE file makes the CD perfectly identical to the original CD.

    FLAC supports only fixed-point samples, not floating-point. This is to eliminate any rounding errors to ensure bit-perfect reproduction. It can handle any PCM bit resolution from 4 to 32 bits per sample, any sampling rate from 1 Hz to 1,048,570 Hz in 1 Hz increments, and any number of channels from 1 to 8. Channels can be grouped in cases like stereo and 5.1 channel surround to take advantage of interchannel correlations to increase compression.


    More specifics on FLAC

    http://www.swee****er.com/expert-cen...udioCodec(FLAC)

    H9
    Last edited by heiney9; 03-29-2006 at 09:18 AM.

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