How to make mp3 sound better

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Whiletrue audiophiles might never accept lossy compression styles as a homestandard just for the convenience factor, many of usdo area an extremely high priority on the manyconveniences readily available by the MP3 format. So we’re left through aquestion: How do we make sure we’re obtaining the most from ourMP3 collections?


Before also thinking about evaluating standardsof quality, it’s crucial to understand also that “this waylies madness.” Audiophiles have wrestled for decades to achieve“objective” dimensions that would sensibly represent thequality of a recording. And while tright here are many objectivemeasurements that can be produced any provided signal, it’sessential to understand that the math of audio measurement andthe subjective experience of high quality are 2 different pets.Furthermore, the mechanics of lossy compression (questioned in Chapter 2) more or less nullify the validity of justabout any type of objective criteria. In various other words, the only tests thatissue for MP3 audio are subjective tests, i.e., real-human being listeningtests. Your ears don’t lie. Even so, it’s possible thatthe file you encode to your very own requirements now can finish up beingplayed on much better devices tomorrow, so it pays to shoot fortop quality a small over your own thresholds.

The the majority of important point to save in mind once testing for MP3 qualityis that your computer more than likely isn’t the best location to perform it.How’s that? Unless you’ve invested a fair sum in high-endcomputer audio tools, opportunities are that your house stereo sounds alot much better than your computer. And if you’re planning to keepyour MP3 repertoire about for a long time, your residence stereo might verywell be the ultimate location for your MP3 papers. Since yoursound card and also computer system speakers may mask a whole lot of subtlety,it’s essential to eliminate those components from the testingchain so that you can tell which limitations are introduced by yourhardware and also which are introduced by the MP3 encoding itself. Inother words, you desire to isolate the encoding as much as feasible andoffer it an optimum setting in which to be tested.


Since “CDquality” is our benchmark here, you want to get your MP3s ontoan audio CD. To run this test, you’ll require accessibility either to aCD burner or to a committed MP3 playearlier device. Find a couple ofsongs via which you’re well-acquainted, preferably ones thatincorporate a wide variety of instruments, consisting of those from the brassand also strings households. It’s frequently much easier to detect limitationsin the MP3 codec via non-digital music, and also the brass and stringfamilies perform a specifically excellent task of putting the codec to the test.However, it’s likewise essential that you choose music you enjoypersonally. To be well rounded, you can want to select one each ofyour favorite jazz, classic, and rock tracks, for instance.


Note

If you have a portable or residence stereo MP3 player, simply patch it intoyour stereo as defined in Chapter 3, and also load itup with encodings produced as defined in the following section. The sameethics described in this area use whether you’reworking from a test CD or from a specialized playago gadget.


Next, you’ll should conserve a referencetrack for each song, definition you should rip uncompressed versions ofeach track to your tough drive (generally in WAV format, though Mac OSusers will certainly want to usage AIFF format). See Chapter 5, for details on ripping tracks straight fromCD without encoding them. For the actual compression, you’lldesire to use the greatest top quality encoder you have the right to uncover (aacquire, seeChapter 5),<29> and encode each track avariety of times, at various bitrates. As you encode, offer each filea descriptive name, consisting of its bitrate. For instance, you might usethe complying with scheme:

Improv.Spacious.64.mp3Improv.Spacious.128.mp3Improv.Spacious.160.mp3Improv.Spacious.192.mp3Improv.Spacious.256.mp3
Automating Test Encodings

If the procedure ofencoding the very same track over andover aobtain sounds tedious, it is. Here’s a manuscript you can useunder Unix/Linux or BeOS to automate the process, assuming you havethe LAME encoder somewright here in your path. This need to be exceptionally straightforward tomodify to work with other encoders:

#!/bin/shFileName="$1"# Start a loop and also encode as soon as at each bitprice specifiedfor i in 64 96 128 160 192 256; perform echo Creating "$FileName".$i.mp3 lame -ms -b$i "$FileName".wav "$FileName".$i.mp3 echodoneIf you’re on a DOS/Windows machine, here’s a batchfile that will certainly accomplish the exact same effect:

Echo offrem examplecollection filename=%1if not exist %filename%.wav goto errorrem The complying with must go on a single line -rem We had to wrap it to two lines for this bookfor %%B in (64 96 128 160 192 256) execute lame -ms -b%%B %filename%.wav %filename%-%%B.mp3goto exit:error echo Documents %filename%.wav does not exist goto exit:exitWhether you’re running the the bash or the DOS variation,conserve the script as a paper in your system’s course with a filenamelike “TestEnc” and also then run:

TestEnc filenameassuming your input file is calledfilename.wav. Of course, these scripts assume thatLAME can be uncovered in your mechanism course as well.


Once you’ve encoded each sample at a range of bitrates,you’ll need to interpret them back to WAVformat and also burn the resulting tracks to an audio CD (although yourburning software might take treatment of this convariation for you; check out Chapter 5 for details). Since the filenameswon’t be existing on the audio CD, take treatment to print out orcompose down the track numbers and the matching bitprices soyou’ll have actually a recommendation sheet in the future. Once your audio CD iscomplete, find the greatest quality stereo you deserve to (yours or afriend’s), grab your recommendation sheet, dim the lights, relax,and also listen through the CD. While you might want to skip ago and also forthbetween the recommendation tracks (which will sound the same to theoriginal CD audio tracks) and the encoded tracks later, you shouldfirst listen to the disc all the method via. Don’t be tooquick to flip earlier and forth in between tracks, as that will certainly just leadto schizophrenia and also ear fatigue. The idea is to internalize the“flavor” of the tracks relative to one another. Eveningsmay develop the ideal listening environment, as you’ll likelyget less ambient noise and less sensory competition from vision(assuming some darkness). If you’ve been listening to loudmusic or noises during the day, save the test for anotherday—your ears will certainly currently be fatigued. Self-run audio testsutilizing your own hearing as a “benchmark” should alwaysattempt to isolate variables and also incorporate a best-case scenario,against which every little thing else need to be measured.


Note

If your residence stereo or entertainment system contains an on-boarddigital-to-analog converter which provides settings for surround soundor for various room impacts (concert hall, tiny room, and so on.),it’s important to disable these options and also make sure yoursystem is collection on the defaults. If you use an equalizer or other audio“enhancing” gadget, disable it or run it flat (unlessit’s a “set-and-forget” processor very closely tunedto neutralize a certain room). You’re testing your encodingsright here, not your tools. Artificial interferences in signal flowwill certainly weaken the integrity of the test.


As you listen, take note of the the majority of subtle sounds in the referencetrack, and also attempt to identify whether those sounds are still present inthe various encodings. Can you hear the clarinetist taking thatbreath just prior to his solo? The sound of the guitarist’s handsgliding over her strings? What around the sense of room (soundstageexpansiveness)? Can you pinallude the place of various instrumentsin the recording studio as accurately via records that have gonewith the MP3 process as you can with the reference track? Whataround dynamic range? Are you detecting specific subtleties of the highand low varieties being chopped off or smeared out? Perhaps mostimportantly, do the MP3 encodings have actually a feeling of“presence?” Can you cshed your eyes and also imagine that theperformance is taking place there in your living room? Does a givenencoding make the performer sound sort of “mechanical” or“electronic?” Does the performance seem to be even more ormuch less intense with any of the encodings? Do any type of of them carry out a bettertask of making you desire to tap your foot or sing alengthy or dance, or doany of them make you feel edgy, or bored? Do the MP3 encodings sound“hollow” or “swishy” to you? Chances are,you’ll be amazed to uncover simply exactly how a lot high quality has actually beenshed in the 128 kbps and also reduced encodings.

The bitrate at which you literally cannot tell the difference betweenthe reference track and the MP3 encoding is the bitprice at which youshould start encoding your MP3 tracks, offered you’re willingto part with the added disk room this will certainly consume (of course, ifyou’ll be burning most tracks to writeable CD for permanentstorage, this may be much less of an issue). To be really safe, and tomake certain your tracks will certainly sound excellent no issue what playago systemthey finish up on one day, encode at abitrate higherthan the one at which you couldn’t tell a distinction.

If you don’t have actually accessibility to a CD burner, then your following bestbet is to affix your sound card’s line-out jack to one ofyour house stereo’s inputs, and try similar tests. However, keepin mind that unmuch less you use a fully digital transfer system (i.e.,using digital coax or optical cable from the sound card to yourdigital receiver or exterior DAC), you’ll be hearing thelimitations of your sound card’s digital-to-analogconverter.


Audio Test Checklist

To set up a test favor this in a hurry(actually, it’s best not to hurry when doing points like this),remember these easy steps:


Choose a referral track from your collection via whichyou’re familiar. Look for a referral track via a broad varietyof tools and not too a lot thickness. A wall of guitar distortionis not a good alternative, though you’ll gain blended results withright electric guitar under miscellaneous encoders. Well-recordedacoustic guitar, vocals, strings, and also brass will certainly present you moreconstraints in the MP3 codec than difficult rock. Rip the recommendation trackto uncompressed WAV or AIFF format.

Using the best encoder you deserve to uncover,encode the recommendation track at a selection of bitrates, making use of defaultsettings in the encoder. Alternatively, test assorted encoders at thesame bitrate.

Burn thereferral track and the decoded encodings to an audio CD. Keep a liston paper of all the tracks going onto the CD.

Find the beststereo you have the right to, relax, close your eyes, and just reap the music.Don’t begin analyzing closely or paying unique attention tosubtleties and nuances until after you’ve calm into themusic.


As you understand, computers keep and also manipulateinformation—consisting of audio information—digitally. Butyour ears are analog devices, and also so are speakers.<30> Somewherein the process of obtaining indevelopment out of your computer system and intoyour ears, the signal need to be converted from digital to analog. Thetool that affects this convariation is called thedigital-to-analogconverter, or DAC, and also its roleis vital. The high quality of the DAC plays a vast part in the overallquality of the resulting audio pouring from your speakers orheadphones.

In the situation of most stock sound cards, the DAC is a component of thecard’s chipset. However, some higher-end sound cards offerdigital outputs, which have the right to be hooked up straight to the digital inputof a digitally equipped stereo receiver or pre-amplifier. If yourreceiver or amplifier doesn’t have digital inputs(they’ll be clearly marked), you can purchase an outside DACor use the DAC constructed right into a DAT deck, Minidisc player, or DCC, whichwill then sit in between your computer and also your receiver/pre-amp. Thequality of external DACs is regularly directly pertained to their cost; aextremely high high quality DAC have the right to cost $1,000 or even more, though you need to beable to pick up a suitable design for a few hundred bucks.

In any kind of instance, by turning the job of conversion over to a dedicatedunit, you deserve to bypass the frequently bad high quality integrated DAC on mostsound cards, and obtain a far better resulting sound stream out of yourmechanism.<31>When purchasing a sound card, make sure it has digital outputs inaddition to the typical line out. If you’re severe abouthigh quality, do some research study virtual to discover out which cards have thefinest on-board DACs. If you’re really, really severe, considera high-finish outboard (external) DAC.

On the flipside, the reverseprocess—analog-to-digital conversion (ADC) may also come right into play, dependingon your requirements. If you setup to encode music from analog sources suchas actually tapes, LPs, or microphones, you’ll likewise appreciate the extrainput top quality you’ll get by making certain your resource signal isstored in the computer system after having actually passed through a high-quality ADC(either onboard or outboard), fairly than the one constructed right into youraverage sound card.


MostGUI MP3 players include some kind of equalization mechanism,generally accessed by clicking a switch on the player’sinterchallenge labeled "EQ.” Bringing up the equalizernormally screens a row of sliders (a lot of frequently 10, though tright here couldtheoretically be any number of them). So, what precisely isequalization, and what does it gain you? The simplest means toconceptualize equalization is to think of the bass and also treblecontrols on your home stereo, and also imagine that you had actually a separateknob for each of many a lot finer slices of the frequency spectrum,affording you a lot tighter control over the resulting output signal.


The allude of equalization, of course, is to make the resulting audiosound better. EQ have the right to be applied to compensate either for poorlyvideotaped audio, for constraints in your speaker quality or architecture, orfor the speaker placement or acoustics in the listening room. Theultimate objective of equalization is to obtain a “flat”frequency response (for this reason the name“equalization”)—one in which the signal does notsound “colored” by the signal handling chain, storagemedia, or playback equipment.<32> Equalization have the right to additionally be used to eliminateaudio artifacts stored in the original recording. For example, youmay be able to partly correct a recording via an annoying 60Hzhum, or to partially remove some of the scratchiness of encodingstaken from LPs (though the last can be pretty tricky, sincescratchiness frequently crosses many kind of different frequencies, and youdon’t desire to throw the baby out through the bath water).

Regardless of these advanced capabilities, many kind of (if not most) world useequalizers not so a lot to correct for anomalies regarding rise thefrequencies they prefer and also to diminish the ones they don’t. Forinstance, hip-hop fans might want to pump up the bass frequencies, whiletimeless listeners may want to “sweeten” the strings.

Before you go tweaking your equalizer’s sliders through wildabandon, think about the equalizer as something to be experimented withgently and systematically. Listen very closely to the resulting soundafter each adjustment, and pay attention to just how manipulating onesub-band also affects your perception of others—diminishing onesub-band also have the right to cause others to sound more prominent. Keep in mind also that ifyou uncover you need to equalize greatly to compensate for roomacoustics, negative speakers, or a poor sound card, you have to consideraddressing these troubles straight. Equalization is a band-aid, not apanacea. Be conscious of the potential for over-equalization, and of theconstraints of EQ ethics in general:


Without the majority of expensive test devices, you have actually no concrete goalto aim for—you’re simply tweaking until something in thesound “feels” better for one factor or an additional.

See more: Asus Splendid Video Enhancement Technology Windows 10, Asus Splendid Video Enhancement Technology

EQ bands come in precharacterized widths and slopes, yet your equalizationrequirements don’t—they’re frequently more“fuzzy” than the usual collection of EQ bands enables for(it’s sort of choose trying to apply mascara with a hairbrush...and no mirror).

Analog equalizers can present distortions, specifically phasedistortion. Digital equalizers have the right to minimize some of these results.


It’s basic to confuse louder and also brighter sound for bettersound. Optimum top quality is achieved when music sounds as organic aspossible—equalize via an ear toward a herbal soundsetting. Over-equalization can conveniently degrade sound quality. Invarious other words, the answer to the question, “Why equalize?”is regularly “You shouldn’t, unless the instance demandsit.” It’s much easier to destroy the sound than to enhance it.Experiment through your EQ, yet don’t overdo it.


Artificial Audio Enhancers

Everynow and then, you’ll come across a product that claims toboost the high quality of computer system audio dramatically. Generally, theseproducts (QSound’s iQ, http://www.qsound.com, being an example) work byrunning a series of proprietary algorithms over the outbound audiostream and also applying digital effects to the stream simply before itheads for your sound card. Much favor the sample impacts that comewith some sound card chauffeurs, or the presets found in some hometheater amplifiers, these products create the illusion that the soundphase extends out beyond the edge of your speakers, generating a 3Dsound stage on the fly. These products deserve to likewise take a monophonicsound stream, such as you’ll frequently gain as soon as listening toSHOUTcast or icecast streams, and “turn them intostereo.”

Do these assets work? Well,there’s no question that the effects are fairly dramatic, andyou’ll a lot of absolutely notice a distinction over normal playback.But the fact is, these products are producing a signal thatisn’t current in the resource by playing auditory tricks withchannel changing and also phase relationships (bouncing sound wavesversus one another). What these commodities execute is unherbal andunrealistic, and also while they may make a cheap computer sound systemsound even more dramatic, they absolutely won’t bring you any closerto the artist’s vision of exactly how the music was intended to sound.

If you select to experiment with assets like iQ, keepin mind that the signal you’ll be hearing is not“true.” This may or may not matter to you, depending onyour perspective. My position is that effects choose these are bestscheduled for usage through games, but should be disabled as soon as listening tomusic.


While you need to, of course, equalize as necessary to hit the sweetspot that functions for a offered case, there’s one commonlysupplied configuration of which you may want to be aware: The classic"Fletcher-Munson” curve, which takesbenefit of the reality that the ear is not as sensitive to low andhigh frequencies as soon as music is being played at low volumes. Hence,increasing these frequencies rather over normal deserve to aid music tosound even more organic at reduced volumes (Figure 4.1).


Note

Interestingly, the attribute of the loudness switch on your receiveris similar; use an Fletcher-Munchild equalization curve to the musicrenders it sound even more organic at lower quantities.


*

Note that many MP3 equalizers, such asWinAmp’s, let you storeequalization curves as presets, which can be loaded up aget laterwithout painstakingly re-developing them. Depending on your player, itmay also be feasible to store a prime equalization curve straight inthe MP3 file itself, so you deserve to optimize every one of your songs’equalization curves separately. This capcapacity is dependent onthe fact that the ID3v2 specification enables for a huge array ofmeta-data storage capabilities in MP3 files; in various other words, you mustbe utilizing an ID3v2-compliant decoder qualified of storing EQ presets. Atthis writing, this capability continued to be pudepend theoretical, though ithave to come to be a realistic possibility as the ID3v2 spec builds moremomentum. See the ID3 area of this chapter for details.


Since different tracks might require different equalization curves,WinAmp allows you associate anEQ precollection withany provided track. Here’s how to associate an EQ curve with atrack:


Play the track normally, and also push AUTO in the EQ interchallenge.

Dial in your EQ curve.

Click the Presets button and navigate to Save → Autofill Preset.

Allow WinAmp to associate the present track’s filename through thepresent EQ curve.


After producing an association in between a track and an EQ curve, theassociation is stored by WinAmp in a document namedwinamp.q2 in the WinAmp installation directory(the file cannot be edited by hand). Any time AUTO is permitted in theequalizer and that track is played, the preferred EQ curve will certainly snapinto action.


Unfood preparation Bad Transfers

Eextremely so frequently, you might finish up via an MP3 file that’sbeen corrupted during transport somehow, commonly by being transferredin ASCII mode fairly than binary. If you have to encounter one ofthese, search the Internet for uncook.exe,Uncook95, or OK Unprepare, all of which carry out essentially the samething—repair the damage that was done to the file duringdeliver and make it playable aobtain. Linux and BeOS customers might desire tokeep a copy of mp3asm (http://www.ozemail.com.au/~crn/mp3asm.html) aroundfor the very same function.

If you’re making use of a recentinternet browser and also the web server you’re accessing has actually been collection upeffectively, this need to never before happen, though it’s nice to knowthere are devices easily accessible to correct the instance if it does.


Note

In the majority of cases, the equalizers built into MP3players will have no impact on the audio stream once playing audioCDs, since CD audio is regularly routed straight from the CD player tothe sound card without relocating via software application initially. In this situation,the MP3 player is simply supplied as a convenient interconfront onto the CDtransport’s manage butloads. However before, tright here are plug-inseasily accessible that will “steal” the CD audio signal and routeit via the MP3 player (the NullSoft CD/Line Input plug-in forWinAmp, with the “sampling” alternative permitted, for example).See Section 4.5 in thischapter for details. Once the CD plug-in has actually been enabled, you shouldhave the ability to usage the equalizer and also assorted visualizers to communicate withCD audio.


<29> The test describedbelow can likewise be used to test various encoders against one another.The only distinction is that you’ll desire to encode the referencetrack at the same bitrate, however with differentencoders. In reality, you may desire to encode at miscellaneous bitrates witheach encoder in your test, so you deserve to determine whether a givenencoder excels at low bitprice encodings however falls dvery own at higherbitprices, for example.


<30> Or, at leastern, a lot of of them are; totally digital PCM speakersare beginning to appear on the sector.


<31> Of course, the rest of your device need to beof high top quality before you go spending money on a DAC. Putting anexterior DAC in a system with poor speakers, for instance, probablywon’t bring about noticeably better sound.


<32> Keep in mind, yet, thatmany recording studios usage equalization to addshade, not to rerelocate it—a fact which drives some audiophilesnuts.


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