Converting MP3 To Wave

A question has come up regards including an MP3 to Wave converter when delivering programme audio to radio stations who can only use Wave format in their playout systems. Now, I am concerned about the audio quality of a file that has been converted from MP3 to Wave. Is it even wise to consider doing this? Will there be further file compression involved, or does it result in a good audio quality file?

Bernie.

Will there be further file compression involved, or does it result in a good audio quality file?

No further compression, but the resulting wav file won't be any better than the MP3 - it simply can't be. All the damage is done when compressing to MP3 in the first place.

Sadly I hear that mp3 distribution is becoming the norm for some record companies. While you are lucky that your playout system uses uncompressed files, some use alternative compression systems (like mpeg1 layer 2) so the audio will be subjected to two different compression systems. If you are also transmitting on a digital network then the audio will go through yet another compression algorithm. The problem with all these algorithms is that they assume that the audio is pristine before being compressed and they make no allowance for audio that has already been compressed.

I'm now hearing severe bit reduction artefacts on many UK radio stations (including BBC national channels) and also regularly hear aliasing on the output of one major radio station.

It would be great if the audio, once compressed, could remain compressed all the way through the transmission chain but, given the different codecs already in use, this is unrealistic. The best we can hope is that bandwidth and storage increases sufficiently to make the use of compressed formats unnecessary before the transmission stage.

Cheers

James.

Will there be further file compression involved, or does it result in a good audio quality file?

No further compression, but the resulting wav file won't be any better than the MP3 - it simply can't be. All the damage is done when compressing to MP3 in the first place.

Thanks Steve.

The best we can hope is that bandwidth and storage increases sufficiently to make the use of compressed formats unnecessary before the transmission stage.

Nice idea - but it will never happen.  There will always be some reason for compressing file sizes.

Bandwidth is like a road - you build a road and it gets congested with cars, so you widen it.  The wider you make the road, the more cars will want to use it - more importantly, smaller cars means even more cars can occupy the same space.    Think of the storage space in any house, the junk always accumulates to equal the amount of space available.

The only thing which would put a stop to all this nonsense would be the end-user complaining about the product and refusing to buy it, but you're making a mistake if you believe any more than 0.5% of the listening public even care, never mind know about all this stuff.

The record companies can get away with offering MP3 as an audio standard for the simple reason that few people know (or can hear) it sounds like c**p and the majority think it sounds good.

We're actually reaching a point in the timeline where there is a whole generation of listeners who have only ever used MP3's - CD's are as defunct as 78's, as far as they are concerned.

We're actually reaching a point in the timeline where there is a whole generation of listeners who have only ever used MP3's - CD's are as defunct as 78's, as far as they are concerned.

And it's probably not that they couldn't tell the difference if they were educated to hear it... but that they would decide not to care.  To those of that mind, quantity (thousands of tunes on an iPod) wins out over quality (an hour+ on a CD).

Sheer numbers trumps substance.

I grew up in the 1960s listening to KJR and KOL in Seattle on a hand-held, monaural, am transistor radio with its fair share of static (from me being about sixty miles north of Seattle).  Somehow, I came to love most of the "quality" songs I heard.  And, surprise, surprise - most of the songs I came to love are the ones which have survived and are still played today on oldies stations (now in stereo, with CD quality).  The moral of the story being that I was obviously not the only one who came to love those songs - in spite of the mediocre audio quality.  From time to time, this forum gets a question on the order of "how do you write a hit song?".  Of all the advice offered, none comes close to saying "make certain it is recorded with pristine audio quality".

A bad song will not become a hit simply because it is recorded with and played back on top of the line equipment.  And a good song will not languish simply because it is played back on poor equipment.

I understand the value of high fidelity.  But, for most of us, there is more to music than the quality of the playback.

am (AM) transistor radio with its fair share of static

Didn't we all... who are of some age.  Nevertheless, that's all that was offered back then.  Not even FM stations played the most popular stuff, unless it was Easy Listening or Classical or older 40's Jazz.  The travesty nowadays is: copy/save, copy/save, copy/save... all to your heart's content and all in what the masses believes is that magical digital domain where everything stays pure.  

Except --  we know what happens to multiple mp3 saves.

And then I run into this... Consumers wanting better quality?

it's probably not that they couldn't tell the difference ...  but that they would decide not to care.  ... quantity wins out over quality.

Sheer numbers trumps substance.

Cal, not to be ornery but just to make certain my point is understood.  As I'm sure we all understand - the quality of a song is not necessarily correlated with the quality of the sound (listening medium; e.g., staticky AM radio).  If the quality of the song is high (in the mind of the listener anway), it may not matter that the quality of the audio is low.  I don't necessarily see it as a bad thing that folks would give up audio quality (lower bitrate) in order to have a larger collection of quality songs (however they define them).  Substance need not be trumped by sheer numbers if substance is defined as the quality of the songs rather than the quality of the audio.

if substance is defined as the quality of the songs rather than the quality of the audio.

Yep, I'm sure that's how we thought of it.  In fact, I probably still would be okay with that even today, except... in some past Age.... I stumbled onto Cool Edit 2000, and a mere $69 changed everything.

Bernie,

I would not concern yourself with it too much.  You might, however, look into the possibility of using high-complexity AAC coding.  US broadcasters are finding out that our digital HD radio doesn't play well with mp3 at all.  While AAC is still going through the double-compression process, it doesn't seem to be nearly as awful sounding on the air.

Emmett

A question has come up regards including an MP3 to Wave converter when delivering programme audio to radio stations who can only use Wave format in their playout systems.

What I have had to do Bernie is either FTP all the material and give them a user name thru my domains FTP access for download or overnight mail a burnt CD.  Unfortunately most of these systems will not accept any MP3s--HAS to be .wav--therefore they have option 1 or 2.  One of my clients even has to have the final mixdown normalized to 75% THEN saved as a .wav--some of these on air systems are very fickle.

Just my 2 cents worth....

Smiles,

MM

Yes, there isn't much uniformity amongst the playout systems, some use this format and some use that one .. MPEG 2, Wave, MP3. Everyone is talking about AAC http://en.wikipedia.org/wiki/Advanced_Audio_Coding , but I have only seen it in the context of online streaming, can we use it in Audition, and if not, how do we use it?

I also wonder why people are still complaining about the audio quality of MP3. The digital/binary technologies involved must be either at a very early stage or we have to learn to listen differently .. or even create different sound or create the same sounds differently for this new technology. At a very basic level I know that digital recordings using the binary "on-off" system is leaving out tiny bits of sound or information, and these were supposed to be inaudible, so what is it that we're noticing (that's missing) in MP3 recordings that makes it sound bad? I don't understand the technologists implementing something that would sound bad! The general public doesn't seem to complain at all, only the audiophiles and broadcast people, in which case, don't use it then, no one is forcing us. If the playout formats are no good then go back to tape until the digital formats have been improved or are good enough, I don't hear the photographers, graphic artsists, video editors and writers complaining about their new digital equipment and formats, I'm sure they are delighted with the new digital way of working. If digital audio is truly so aweful then stop using it and that will force the developers to hurry up and develop something usable.

It sounds like you're confusing "digital" with "lossy compression".  The "binary "on-off" system" sounds like you're referring to ANY digital sampling - and that it "leaves out" anything is patently untrue, given enough bit depth & sampling rate.  IMO anyone claiming a good 24/96k system "leaves anything out" on principle (besides noise & distortion) is deluded.

But lossy compression does indeed leave things out, as well as introduce its own artifacts.  This occurs in ANY lossy media format, from JPG pictures, to MPG video, to MP3 audio.  Mostly it's about bitrate, as these common formats look/sound indistinguishable from their uncompressed sources *to most people* at higher bitrates.  This is true of all those media I mentioned, too - a 5:1 ratio on any of those formats looks/sounds GREAT.  The problem is, people usually use higher compression (a rate that is considered by SOMEONE as "good enough) - usually 10:1 - 12:1 or even more.  NOW we get artifacts.

As a side note, I don't think it's usually what's MISSING that tells the tale - it's the artifacts.  I don't pick up a lower color depth or slightly narrowed audio bandwidth or soundstage very quickly - it takes careful perusal.  But JPG "blocks", MPG "mosquito noise", or MP3 "swirlies" catch the attention very quickly.

If I misread your confusion and this is all simple prattling, please forgive me and chalk it up to my need for a 2nd cup of coffee...