sound quality, mp3 vs cd's

[ranthore]

putting together my surround system and was wondering, if i should get one of those 50 cd changer thingys , i do prefer mp3s as i can get exactly what songs i want , but my friend said some of those changers let you make playlists so you can do the same thing, so im wondering, does mp3 music have the same quality as cd if so ill skip that as mp3 files are soeasy to use. and dont take alot of space.

thanks in aadvance for all your advice

 

[ThA tRiXtA]

Hello Ranthore.

To start off, MP3's are smaller in size than CD audio tracks because they are compressed. When you compress things, you lose quality.. in this case sound quality, or more specifically dynamic range.

You can offset this somewhat by encoding your MP3's in a higher bit rate, with the highest possible being 320 KBPS. The average a few years ago was 128 KBPS, but keep in mind even at 320 KBPS you are still compressing the file.

That being said, in my opinion it more comes down to the quality of system your going to pair your music with. If you going to drop the $$$$ on a full range audio system that has high fidelity than you should just drop the extra little bit on a CD player.

In a car maybe, or on a iPod dock or just a bedroom stereo, are you really doing critical listening? My guess would be no. Even in your car, with wind and road noise making your noise floor much higher than it would be in a normal room it is hard to really appreciate the subtle nuances of a song reproduced faithfully on a CD.

Just on a side note, I don't know how many CD's you have, but I would go more than a 50 changer. Sony makes a 400 CD carousel now. I have the 300 disc version and aside from being a little slow swapping discs it works great. The point with a multi disc changer is so you don't have to handle and change your media all the time. 50 will still leave you doing that consistently.

And your friend is right, you can make group lists, playlists, anything you want.

Good luck.

 

[highfigh]

Hello Ranthore.

To start off, MP3's are smaller in size than CD audio tracks because they are compressed. When you compress things, you lose quality.. in this case sound quality, or more specifically dynamic range.

You can offset this somewhat by encoding your MP3's in a higher bit rate, with the highest possible being 320 KBPS. The average a few years ago was 128 KBPS, but keep in mind even at 320 KBPS you are still compressing the file.

That being said, in my opinion it more comes down to the quality of system your going to pair your music with. If you going to drop the $$$$ on a full range audio system that has high fidelity than you should just drop the extra little bit on a CD player.

In a car maybe, or on a iPod dock or just a bedroom stereo, are you really doing critical listening? My guess would be no. Even in your car, with wind and road noise making your noise floor much higher than it would be in a normal room it is hard to really appreciate the subtle nuances of a song reproduced faithfully on a CD.

Just on a side note, I don't know how many CD's you have, but I would go more than a 50 changer. Sony makes a 400 CD carousel now. I have the 300 disc version and aside from being a little slow swapping discs it works great. The point with a multi disc changer is so you don't have to handle and change your media all the time. 50 will still leave you doing that consistently.

And your friend is right, you can make group lists, playlists, anything you want.

Good luck.

If it was an older car, I would tend ot agree but when you consider anything recent, the noise floor isn't all that hard to mask. A few watts into speakers with 87dB sensitivity and you're over 95dB. When the road noise is less than 80dB, that's only 15dB but a lof of music is OK with that. Another couple of watts and road noise is unnoticeable unless it's a quiet passage in Pop, Jazz or some classical, like chamber music.

 

[cfrizz]

Hi Ranthore.

No the sound qaulity of mp3's is not the same as cd's. But then again you can get a badly recorded cd that sounds like crap as well.

Basically it all comes down to how well the music was recorded in the first place that determines the quality of either the cd or mp3.

If you are doing a serious listening session, then use cds. If you just want background music, then a mp3 player cannot be beat. I love hearing music all day long without having to get up to change cds.

Some of the songs are pratically indistinguishable from cd's and others sound even worse then they do on the cd I took them off of!

 

[Adam]

I'd skip the huge CD jukebox if I were you. I think that their time has passed. You can store soooo much more audio on a single hard drive than you would put in a jukebox - and that's even uncompressed audio, so a perfect copy with the same audio quality as the original CD.

Are you set on using MP3, or are you open to using a different codec? I think that 320 kbps MP3s should work just fine on the system that you've been talking about putting together, but there are lossless codecs available.

BTW, we've discussed putting MP3 files onto a DVD and playing them through your Blu-ray player. One single-layer recordable DVD (that holds about 4.5 GB) will store roughly 32 hours of continuous audio that is encoded at 320 kbps.

 

[highfigh]

putting together my surround system and was wondering, if i should get one of those 50 cd changer thingys , i do prefer mp3s as i can get exactly what songs i want , but my friend said some of those changers let you make playlists so you can do the same thing, so im wondering, does mp3 music have the same quality as cd if so ill skip that as mp3 files are soeasy to use. and dont take alot of space.

thanks in aadvance for all your advice

MP3s aren't great and for a real system where sound quality is #1, they won't cut it. CD changers are nice if the discs never need to leave it. If they do, it's not very convenient. If you are just starting to get ideas, think about a music server, a new iPod that can play .wav files or connect a computer with a really good sound card to the system. Some Denon (and other brand) receivers have a USB and ethernet port so an external hard drive can be connected and you can select songs, playlsts, etc from a computer. You could use a PDA or any other network-enabled device, too, like an ASUS Eee, Nokia N.800, Blackberry or Treo.

I have a ReQuest server and the sound quality is excellent. It's controllable via network or IR, RS-232, etc. It can be configured to save everything as bit-for-bit files and/or MP3. The MP3 files are used to synch to iTunes to load into an iPod or for streaming over a network. It can be accessed from any computer that's on the internet, if the user name and password are used on the secure website.

 

[WmAx]

I'll give you the straight scoop, based on actual research, not on my opinion.

MP3s, when encoded with a high quality modern encoder like LAME, and at sufficient bandwidth, are transparent when compared to the source, in most circumstances. It is a rare sample that causes an audible deviation, and even then, chances are, you would need the direct source to compare to in order to find this extremely rare exception.

Of course, if your MP3 source is the internet, there is no telling how they were encoded, and you may likely end up with low quality files.

-Chris

 

[fmw]

I've done bias controlled listening tests comparing WAV files (CD) to 320 mp3. There is no audible difference. I've also listened to the audio that was removed while compressing the music. It sounds like a barely audible breeze. There is a point at which the digital compression becomes audible, however, so the answer to your question is yes or no depending the on the specs of the mp3. It is possible to make MP3's that have no audible degradation of sound and it is possible to make MP3's that sound truly awful.

 

[ErinH]

Guys, do yourself a favor. And be honest...

have a friend make a CD of uncompressed (wav) and 320kbps encoded tracks. Then do some A/B listening tests. Give the friend your results and let him tell you have accurate your listening test was. You'll be very surprised.

A group of us car audio enthusiasts did this in both car and home audio setups. He had all sorts of music (rock, pop, 'audiophile reference', etc). The results were pretty surprising. The leader of the 'experiment' also had us rate our confidence on our tests. 0-100% confidence. That definately made for some interesting results.

I lied to myself for years. It was a surprise to see how hard it was to truly tell a steadfast difference. A lot of other 'golden ears' were also surprised.

 

[OttoMatic]

Yet we hear, and accept, so many descriptions of how the new lossless audio formats are better than the old Dolby Digital and DTS formats (BluRay vs. DVD). What's the difference, really?

 

[davidtwotrees]

Don't buy a giant carousel! Put your money in a music server. I have one and it has changed my musical life. Audio ReQuest was mentioned and they are the industry leader. I just couldn't afford one at the time I made my purchase. They record cds in lossless formats.........I did buy and Escient Fireball SE80 and love it. It only does mp3 and all my music is recorded at 320 kbps. I can not tell the difference on my rig between 320 and CD. If you have the scratch, I would look at the Audio ReQuest servers.....if you are on a budget my server can be had for like $600 dollars. I think it holds 600 hours at 320kbps. It is plug and play and requires NO tech saavy or geek know how. And the gui on screen is much better than any computer set up I have seen.......what ever song is playing, the artwork is used as the screen saver on my plasma. Servers are the Bomb.

 

[TLS Guy]

I'll give you the straight scoop, based on actual research, not on my opinion.

MP3s, when encoded with a high quality modern encoder like LAME, and at sufficient bandwidth, are transparent when compared to the source, in most circumstances. It is a rare sample that causes an audible deviation, and even then, chances are, you would need the direct source to compare to in order to find this extremely rare exception.

Of course, if your MP3 source is the internet, there is no telling how they were encoded, and you may likely end up with low quality files.

-Chris

Who ever did those tests had lousy equipment, and or played a steady diet of pop music! I have a collection of recordings, that I can switch between mp3 files at the highest bit rate, and uncompressed wav. files in Wavelab. On my rig it very easy for listeners to distinguish the two.

Actually on a lot of program the lossy codecs really sound pretty grim.

Opera is another. The Dolby digital sound tracks are not listenable quality. You have to listen to the lossless PCM track to have a listening experience the right side of pleasant. Pretty much all DVD opera buffs have found the same thing.

In lossy codecs the bass looses its robust quality and definition. Singers sound strained. In particular Placido Domingo's voice is significantly altered in timbre. The brass looses its lovely warm bloom.

For what I listen to you can absolutely forget lossy codecs.

 

[skizzerflake]

putting together my surround system and was wondering, if i should get one of those 50 cd changer thingys , i do prefer mp3s as i can get exactly what songs i want , but my friend said some of those changers let you make playlists so you can do the same thing, so im wondering, does mp3 music have the same quality as cd if so ill skip that as mp3 files are soeasy to use. and dont take alot of space.

thanks in aadvance for all your advice

The definite answer is...it depends. Whether you can hear a difference between mp3 and a cd depends on your listening environment, your ears, the codec used to create the mp3, the bit rate and the accuracy of the equipment. You mentioned surround so recall that getting surround out of a 2 channel source also requires digital processing of the original input, which changes it again. Try it out and see how it sounds.

 

[WmAx]

Who ever did those tests had lousy equipment, and or played a steady diet of pop music! I have a collection of recordings, that I can switch between mp3 files at the highest bit rate, and uncompressed wav. files in Wavelab. On my rig it very easy for listeners to distinguish the two.

Actually on a lot of program the lossy codecs really sound pretty grim.

Opera is another. The Dolby digital sound tracks are not listenable quality. You have to listen to the lossless PCM track to have a listening experience the right side of pleasant. Pretty much all DVD opera buffs have found the same thing.

In lossy codecs the bass looses its robust quality and definition. Singers sound strained. In particular Placido Domingo's voice is significantly altered in timbre. The brass looses its lovely warm bloom.

For what I listen to you can absolutely forget lossy codecs.

Yes, such lousy equipment: one of the main standing tests was in a studio control room with B&W 801 speakers and several audio professionals as the subjects. The codec used was LAME, and music types were various. The tests were strictly DBT. Sighted testing does produce substantial bias, even when no real difference is present. The only music that can artifact a good encoder is primarily something with extreme, high amplitude high frequency transients. Constanet soles and harpsichord solos are typically the easiest to mess up an encoding.

Bitrate alone does not dictate 'quality'. A 320kbps LAME mp3 encoding and a 320kbps Xing mp3 encoding are radically different!

-Chris

 

[ParadigmDawg]

I agree with the group telling you to consider a music server. All my CDs are loaded in WMP as WAV files and I use my AVR as the server. The PS3 also makes a decent server if you can't afford a "real" one.

 

[TLS Guy]

Yes, such lousy equipment: one of the main standing tests was in a studio control room with B&W 801 speakers and several audio professionals as the subjects. The codec used was LAME, and music types were various. The tests were strictly DBT. Sighted testing does produce substantial bias, even when no real difference is present. The only music that can artifact a good encoder is primarily something with extreme, high amplitude high frequency transients. Constanet soles and harpsichord solos are typically the easiest to mess up an encoding.

Bitrate alone does not dictate 'quality'. A 320kbps LAME mp3 encoding and a 320kbps Xing mp3 encoding are radically different!

-Chris

I can give you a list of CDs, that if you convert them to a lossy codec, that sound will be quite obviously degraded, and it won't be subtle. It will be instantly and glaringly obvious.

 

[TLS Guy]

I agree with the group telling you to consider a music server. All my CDs are loaded in WMP as WAV files and I use my AVR as the server. The PS3 also makes a decent server if you can't afford a "real" one.

I agree. I have a 250 gig hard drive on my work station, but it is filling up.

My laptop needed a hard dive change, so that was an excuse to buy a 1.5 terra byte hard drive. I will by two I think and set up a mirror system. That is the way to go.

 

[gus6464]

http://www.stereophile.com/features/308mp3cd/index.html

 

[fmw]

Who ever did those tests had lousy equipment, and or played a steady diet of pop music! I have a collection of recordings, that I can switch between mp3 files at the highest bit rate, and uncompressed wav. files in Wavelab. On my rig it very easy for listeners to distinguish the two.

Actually on a lot of program the lossy codecs really sound pretty grim.

Opera is another. The Dolby digital sound tracks are not listenable quality. You have to listen to the lossless PCM track to have a listening experience the right side of pleasant. Pretty much all DVD opera buffs have found the same thing.

In lossy codecs the bass looses its robust quality and definition. Singers sound strained. In particular Placido Domingo's voice is significantly altered in timbre. The brass looses its lovely warm bloom.

For what I listen to you can absolutely forget lossy codecs.

I suspect your tests aren't blind or you are comparing to overly compressed mp3's or badly made ones. What you need to do is listen to the part of the 320 mp3 that was removed during the compression. That will give you a different attitude. Then you can do some blind testing and see what I mean. You cannot put mp3's in a single category. There are many ways to make them. Properly made 320 mp3's are indistinguishable from wav files - any music, any time, any listener, any equipment. Not fiction. Not opinion.

 

[TLS Guy]

http://www.stereophile.com/features/308mp3cd/index.html

I agree with all of that. May son who is an engineer with a lot of expertise in this area did a study with me about three years ago. Lossy codecs are severely wanting. He has got married and is busy, and has a high pressure job on a top secret project at Seagate.

He has now shelved his project to find a different basis for lossy codecs. He feels that data storage is so cheap, plentiful and improving all the time, that there is going to come a time pretty soon where there is no need for lossy codecs, and that we should work towards abandoning them.