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You too can be an audio expert

Discussion in 'Audio' started by Mez, Apr 20, 2010.

  1. Mez

    Mez Regular member

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    Thanks for making this into a sticky and leaving it open to discussion and additional informative links. Although there are some more prestigious audio forums, AD is the only one I have seen to have this one stop information mart. In about an hour you can become a very well informed audio expert.

    I also invite others to post valuable but obscure articles here as well. I strongly suggest interested parties to download the tools and utilities if they think they will need them. Some are on personal web sites. They will not be available for ever. I keep a folder of these utilities and have burned then to a CD just in case. I have gone to look for utilities after I rebuilt my computer only to find they were gone and I had no way to install them on my new computer even though I had a back up of the old HD. I had deleted the setup package.

    As I did some research for an answer for a query in this forum I came across this article. Spoon is one of the world foremost digital audio experts. He posted this gem and I wish to share it with you. It is well worth the time to read it no matter your expertise. The articles are brief for the amount and quality of info given.

    Spoon's soap box

    I was meaning to post this for some time. I have posted this link several times in the forum. This is the best place for it. This is Hydrogenaudio's wiki for the Lame encoder. Hydrogen Audio may be the most respected audio forum on the web. Spoon is a member but not a very active. With the proper settings, Lame will produce a perfect lossy version of a lossless source. Granted every few years someone finds and artifact and posts proof on Hydrogenaudio that the artifact exists. This means a minimum of two audio snippets one the lossless source the other the lossy with the artifact and the time index of the artifact.

    An honorable mention for quality goes to a Helix (Xing/Guess) encoder that might give you an artifact in 1,000 ripped CDs. The known artifacts are high pitched and soft. I have never heard anyone being able to pick the artifact out by ear in the music. Xing is blazing fast vs Lame which is turtle slow when set to high quality. This is very popular HiFi encoder.
    Hydrogen Audio Lame Wiki

    One other ripping tip... dbPowerAmp allows you to rip as CDa. This mode copies both the audio and the original data error information into an audio file for each track. With the burner app you get with the reference version of dbpoweramp you can produce an exact replica on an audio CD or a personally formulated CD with exact replicas of each tract. Good for all you perfectionists out there. I could myself in that group. Just because I can't hear the difference, I like to know I have perfection or the ability to create a perfect replica.

    I strongly suggest everyone to download dbpoweramp 30 day (now 21 day) free trial and install the all major encoders. I believe you can only install them while it is active. I do not know since apparently I have paid the yearly subscription for so long everything still seems to work after I let my subscription laps. After the 30 days 2 utilities still work, both are activated from file explorer so you do not have to access the main app. There is a tool that allows you to see the tag data of any audio file you installed the encoder for. You can also convert audio formats which you have the to and from encoders from file explorer. That is why it is best to add too many encoders instead of too few.

    Audio quality/format info and some source links in AD audio forum
    Last edited: Nov 11, 2010
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  3. Sudds

    Sudds Regular member

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    Nice link there Mez, i do be about the db forums myself.
  4. Mez

    Mez Regular member

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    Here are some gems, these check for audio quality

    Tau Analyzer can produce an audio spectrum track by track from a CD. You can ascertain the max frequencies. If there are instruments that should produce ultrasonic harmonics you should see them in the spectrum. If they are not there either you are mistaken or the audio may have been compressed (made from lossy audio not original). This can be used as a lossless-lossy test. Pure vocals and electronics never produce ultrasonics. Voices peak a 2 kHz ultrasonics start at about 20-22 kHz. The test only makes sense to use on a good lossless audio. Lossy are not supposed to have ultrasonics. You can check the Hydrogenaudio Lame wiki (the link is in this thread) for pitch cutoffs and verify that a 320 CBR mp3 is only a bloated 128 BR file. For example the highest pitch is only 17 kHz but their ought to be some 20 kHz peaks.

    Tau Analyzer and other utilities by True Audio


    AudioTester detects anomalies in audio files such index vs audio discrepancies that would indicate some sort of corruption.
    AudioTester

    MP3-Library is a handy little quality tool for mp3s. It scans for corruption and can fix some corruption by deleting the corrupt element. Often the corruption is only 1 or 2 frames. You can't hear a missing frame or 2. You can also edit some meta data. More often than not tags are the source of corruption since they get edited while the audio does not. It will also allow you to copy older versions of tag data and save them in the newer format. In all cases you can have it back up your old file as you save. I strongly recommend this!
    MP3-Library
    Last edited: Aug 30, 2010
  5. Mez

    Mez Regular member

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    So you think you are a discerning listener, then you ought to check this out. Ethan Winen hosts an Acustic Myth workshop. He pokes fun at what he calls "propellerhead audiophyles". Much of what they claim is so important to sound quality, can't be heard unless the test is not a blind test.

    Then Ethan Winer allows you to hear for yourself things like dither, eq, resampling, consumer vs professional sound cards, microphones, amplifiers, etc. You get to hear for your self professional grade vs good consumer grade. For instance, he captures audio on both a professional sound card and a consumer sound card. I can't tell the difference then he plays and recaptures the sound over and over again with the consumer card. I can't hear the difference after over 100 generations. Still, if he is doing professional work he uses the best, as he should. The point is as a consumer, a professional sound card is really a waste. This is a must for anyone that wants to be an informed listener.

    Acustic Myth Workshop
    Last edited: Jul 13, 2010
  6. Mez

    Mez Regular member

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  7. Mez

    Mez Regular member

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    Here is some CDA info...

    CDa/CDA is how audio is stored on an audio CD. Below is a direct quote from wizbit.net. I would have linked it but this is succinct enough to cut and paste and this may outlive the link. Because the format comes with extensive error checking, I have heard but can't find the quote now (I will post if I find it), that audio CDs are produced in a way they are a bit hard to read. CD players come with a tool to use the error information better than what is available to computer CD readers, again by design. The error checking problem can be circuvented by using different error checking info such as accurip. accurip.com

    A comment... dbPowerAmp allows you to create a CDA file. I suspect it incorporates the audio, header and error checking info for that audio track so you can burn an exact copy of that track without the rest of the tracks. The high end subscription includes a burn program which must intelligently burn the file back as an audio CD as a perfect duplicate versus a super good version of the tract.
    Last edited: Sep 22, 2010
  8. Mez

    Mez Regular member

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    Methods for copying protected CDs


    Both dbPowerAmp and EAC prebata 3 ignore simple copy protection. For more involved protection try using AnyDVD.

    For those of you interested in EAC nitty gritty, this extremely informative thread concerning ripping in general and will be a reward for the curious.

    A HA discussion about EAC Recently this discussion was 'gutted'. Much of the pro-DRM removal posts were removed. I will paraphrase... 'if your software reads the disk as a player reads the disk you can legally avoid DRMs'

    EAC prebeta 3!
    Last edited: Mar 19, 2012
  9. Mez

    Mez Regular member

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    Audio management reviews

    A comment, many of these rip CDs but I would use a dedicated ripper. MM 4 will upgrade to put it in the same league as EAC and dbPowerAmp and I will still use those but if you aren't going to use the big 2, MM4 is the only good choice for an all in one audio manager.

    I use all of these but since I have an extreme library and prefer the busy UI, I normally use Media Monkey but I use all of these because each does some tasks better than the rest.

    Starting with Media Monkey

    Media Monkey has a busy screen interface, easy to use, best for managing large collections and users that have special needs. This app can assimilate custom routines written by users who are VB programmers. These will accomplish specific complex trasks such as, building you a list of released music that you don't have for a an artist you pick, reverse ratings-normally user ratings are downloaded from the computer to the player this uploads the ratings from the player to the computer.
    Media Monkey and other Reviews Cnet

    Why I love Media Monkey

    From the Media Monkey board

    Winamp
    Uses elegant minimal user interface. Plays a few more formats than Media Monkey in a native mode. Has some nice custom features built in that you would need to find a script if you were using Media Monkey.
    Winapm review Cnet

    Winamp review

    From Winamp board why it is the best

    Foobar
    Not nearly as popular as the rest on this page but has powerful tools not seen in the other audio managers on this page. Popular with audiophiles and caters to that audience. It is a must have for any audiophile.
    Foobar2000 Cnet

    Itunes
    Popular because it is bundled with Apple products. It uses a minimal UI.


    WMP
    Popular because is is bundled with all MS OS products. It uses a minimal UI.
    WMP review cnet

    Comparison reviews
    A comparison review for the big 4

    General reviews

    ipod sync software review
    Last edited: Nov 13, 2010
  10. Mez

    Mez Regular member

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  11. Mez

    Mez Regular member

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    Conversion schemes

    Unless you are converting from lossless you will lose some fidelity in a conversion. If you convert wisely, the loss will not be hear able.

    Pay attention to formats and format density. If you installed dbpoweramp you can see all the meta data from and audio you have installed a codex for from file explorer. You really need this to properly convert. If you convert to something that contains less data you lose quality. If you convert to something that contains more data you use up more space and have put lower quality into a higher quality container. You have falsely labeled you lossy file. These mislabled files if shared have brought about a mistrust of lossy files. Many users only trust lossless files.

    MP3 VBRs have the most density, mp3 ABRs, m4a, ogg, wma, and real media the next, mp3 CBR next and then lossless. Do not confuse density with bit rates. Lossless is about 1,400 CBR so they are very high quality. You want to try to match density and bit rate for the best conversion. You don't want to try to put dense data in a less dense format without upping the bit rate. The reverse will give a false indication of the quality of the audio.

    I suggest unless you keep a lossless copy, convert to some form of mp3 since everything play them. Then you will not have to convert them again. Use the mp3 ABR format for m4a, ogg, wma, and real media and you can keep the same bit rate. If you convert the more dense format to an mp3 CBR (the standard mp3) you will lose hear able quality in lower than 190 BR, especially if you are converting 128 BRs or lower.
    Last edited: Mar 5, 2011
  12. Mez

    Mez Regular member

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    Dynamic compression of music

    This is where during mastering of an audio the loudness of the loudest peaks are 'chopped off'. There is a backlash of audiophiles against this technique. They abhor the 'unnecessary' tampering of the music. To understand why this is done you need to understand the Fletcher–Munson effect. I do not take sides on this issue but there are very good reasons to compress the music, mainly because it sounds better.

    Fletcher–Munson "Loudness, its definition, measurement and calculation" Journal of the Acoustic Society of America Oct. 1933

    Fletcher–Munson Curves

    In brief, humans can't hear high or low pitches well. As we approach the limits of our hearing ability, the tone must be much louder. We hear in human voice range the easiest. As we approach our hearing limit the loudness in dbs has to increase logarithmically to hear the tones at all. In music, the highest pitches are harmonics which are softer than the primary notes. We will hear the higher notes and tones only if the music is played loud. The louder the music the more highs and lows we can hear. The other way to 'fix' this is to boost the loudness of the highs and lows.

    On the soap box
    The other fall out of Fletcher–Munson is that although humans can hear 20 kHz, adults can't hear 20 kHz in music. A 30 yr old can barely hear 15 kHz at 120 db let alone 30-40 db as in the music. Persons believing that they can hear the difference between lossless and a good mp3 that cuts off at about 20 kHz is mistaken. To faithfully capture 30 khz requires huge bandwidth. Not only is the basic information of a 30 kHz 1000 times more than a 30 Hz tone but the sample rates have to be much more frequent for the whole piece to be able to capture the high pitched peaks faithfully. Because in a CDa format, space is reserved for a maximum bandwidth of ultrasonics, most of the data is empty , all 0s. 60 minutes of silence takes the same space as 60 minutes of ultrasonic audio. You can faithfully capture all hear able audio in a 200 BR audio even though lossless is 1450 BR. The belif that you must be losing something between lossy and lossless is false. The reality is, you MIGHT be losing some ultrasonics. Electronic instruments and vocals do not have ANY ultrasonics. The difference between the 2 is lossless faithfully captures ultrasonics lossy ignores them. With today's cheap storage you can easily afford to archive in lossless. However, to believe you can hear the difference is very wrong.

    Back to the Dynamic compression of music... by increasing the volume of the lows and decreasing the loudness of the highs, you can play the music louder so you can hear it more clearly. It is not a 'commie plot'. You will not be able to hear the compression you need software analysis to measure the loss of dynamics but you will hear the highs and lows more clearly if you play it loud. I personally would chose to equalize the music and leave the dynamics alone.
    Last edited: Apr 9, 2011
  13. Mez

    Mez Regular member

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    AMR files
    What is Adaptive Multi-Rate (AMR)
    Adaptive Multi-Rate (AMR) is an audio data compression scheme optimized for speech coding. AMR was adopted as the standard speech codec by 3GPP in October 1998 and is now widely used in GSM and UMTS. It uses link adaptation to select from one of eight different bit rates based on link conditions.

    AMR is an audio format which is extensively used in mobile devices in various applications ranging from normal audio player/recorder to VoIP kind of applications. AMR can be further categorized as: AMR-NB( NarrowBand ) and AMR-WB( WideBand ).

    AMR-WB ensures that speech quality is optimized in a mobile station by verifying its ability to determine when to request a change to another codec with either more or less error correction and protection as signal quality changes. AMR-NB (Adaptive Multi-Rate Narrowband) is a vocoder employed in low-bitrate applications like mobile phones.

    AMR is also a file format for storing spoken audio using the AMR codec. Many modern mobile telephone handsets will allow you to store short recordings in the AMR format, it should be remembered that AMR is a speech format and is unlikely to give ideal results for other audio. The common filename extension is .amr.

    Free AMR audio player software - AMR Player
    AMR Player is one freeware to let you can play the AMR audio files on your PC, and support to convert common multimedia file formats ( such as MP3 or WAV) to audio AMR/AWB format, or output AMR audio files to MP3/WAV audio format.

    The usage of AMR Player is very simple, click "Add Files" button of the main interface, select the one ".amr" file, then click "Play" button, AMR Player can decode the AMR audio file, then play the audio/music for you. If you want to convert AMR to MP3 format, just select one AMR files that you had added, click "AMR to MP3", input one MP3 file name, the free program can convert your AMR files at once, both MP3 and WAV are popular audio formats.

    Here is the link and there is a player at this site
    http://www.amrplayer.com/
  14. Mez

    Mez Regular member

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    DRM removal

    Great article and better than writing it myself.

    AD audio information sticky

    There is software that will remove the DRMs like tunebyte. You can even use audacity to record the audio as you play it but it is much slower than the professional removers.
    Last edited: Aug 23, 2011
  15. Mez

    Mez Regular member

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    Making a perfect copy of an Audio CD -

    You need to buy dbPowerAmp Reference. That includes a burn app. You can rip to CDA then you can burn them back to a blank CD. That should make a bit perfect replica of the original. This is over kill in my opinion but if this is what you want to do, this is the best way to do it.

    Explanation- It is the only software that copies the error correction info from the CD as well as the audio. All other packages make up their own error correction information from the audio. That works for a perfect copy, maybe...
    Last edited: Oct 24, 2011
  16. Mez

    Mez Regular member

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  17. Mez

    Mez Regular member

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    Capturing 78s -
    The common misconception is you can capture 78s like 33s NOT!

    You need a 78 needle. The 78 needle is much fatter. The needle is supposed to touch both sides of the groove without touching the bottom. The bottom has dust that a proper needle avoids. A 33 digs in the dust creating much more noise because the dust helps the needle make contact with the sides which carry the audio info. The dust damages the grove and sounds terrible. You needle can't touch both sides at the same time so the fidelity is poor. I would read into the cartridges as well. Some my not add the RIAA equalization to the output.

    You should thoroughly clean your records before playing them. There is information in the various links how to do this best. I suggest a vacuum brush then the water based cleaning as in the Audacity link. Dust adds to noise and can damage your records.

    78 Needle links

    Detailed info

    LP gear 78 needles

    Sure 78 needles

    UK

    I suggest capturing with Audacity. Much can be done to restore the recording to what it was supposed to sound like. Again none of this is a bit obvious to an average person. There are equalizations applied to the recordings and possible equalizations applied by the cartridge. I am not sure the various equalizations applied to the master when the record was produced must be removed. Since that is how the creator thought the record should sound. Still, you ought to be aware of such things.

    When you are done you will have a recording that will sound better than what you will hear playing a 78.

    Much good information about different types of capture, though the author is not an expert in all areas

    What Audacity has to say about capturing 78s
    Last edited: Apr 9, 2012
  18. Jeffrey_P

    Jeffrey_P Regular member

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    78's need a pre Amp with a flat frequency response. It's just not the Needle and cartridge that makes a great 78 --> digital reproduction.

    http://www.soundhifi.com/78.html

    Jeff
  19. Mez

    Mez Regular member

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    If you actually checked out all the links that was the UK link. All the needles in my links come with cartridges. The 78 cartridges save time and effort by eliminating the RIAA equalization found in all 33 cartridges. As the links state, the records have their own equalization which can be removed with audacity. Leave it in, leaves you with the sound intended by the label.

    Jeff what do you mean preamp? The cartridge amplifies the signal enough to move it through a few feet of patch cord. None of these guides suggest using a real preamp. They all suggest plugging the patch cord directly into the sound card. Digital amplification is 100% clean since you only alter the loudness setting. The best preamp in the world can't do that.

    I am glad SOMEONE reads this sticky. I am sure not many do. I was staggered by all that I did not know about playing a 78. Now I know why they always sound so terrible.
  20. Jeffrey_P

    Jeffrey_P Regular member

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    My turntable cartridge does not have enough gain to optimize the input signal to my PC's Realtek HD audio input without generating unacceptable amounts of noise. It has a USB output but really lacks in sound quality. I use analog phono jacks/plugs. I would also have to upgrade the turntable to a model that plays @ 78 RPM and a cartridge.

    I don't know if you've looked into the pricing of classic turntables but they cost as much as $4000.00.

    Here is a link to Thorens turntables which are probably the best of the best in turntable world. All state of the art (if there is such a thing.)

    http://www.thorens.com/turntables.html

    Interesting stuff since vinyl is making a huge comeback. Not only is the frequency range exceptional but good luck adding copy protection. ;)

    Jeff
    Last edited: Apr 10, 2012
  21. Mez

    Mez Regular member

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    If worse came to worse I would repair my old dual it is probably close to those. The design is very close. It has a synchronous motor and a very heavy platter. You can't see a waver on the strobe marks your eyes are more than 100 times a sensitive as your ears. The arm is set to 20ths of a gram. I see it as insanely over kill. The motor finally died I can get a new one for a few hundred bucks. I don't see the need to repair it. I do not see the beauty of vinyl. I captured the vinyl and never touched them again. Magnetic audio is far more exact. Even CDs do not play identical every time you play it. I am certain vinyl is far more iffy. The only reason it is not obvious is human hearing is not very keen or precise.

    CDs exceed the frequency range of human hearing, a baby's hearing. By 20 years old if you have not listened to loud noises, you can only hear 70% of that range. At 30 you can't discern a 190 constant bit rate mp3 over a CD in a blind test. Although you can't hear ultrasonic music it damages hearing more at the same db level than hear able audio.
    Last edited: Apr 10, 2012

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