Dach
With all the talk on this forum about ripping MP3's and sound quality, I decided to do a little experiment. Now, out of necessity (laptops have small drives and I didn't want to get an external drive) I ripped my collection to 96kbps MP3PRO files, and used compatible players. Half the file size, same quality... Or is it? I wanted to know. I built me a DJ rig, but have been unable to test it in a club environment yet. I have my first gig at http://www.tokyodarkcastle.com/ next month, so I wanted to know if I had to re-rip everything. Obviously, 96k is good enough for my weekly college-radio program, but would it be good enough for the clubs?
Tools:
Generic P4 2.8GHz, 512DDR, 60GB 5400RPM, DVD-R, crappy internal sound card
M-Audio Transit USB
Sony MDR-V500 headphones
Software:
Jet Audio 6.0.4
MusicMatch Jukebox 9.0
VirtualDJ 2.02 (Yes, I realize VDJ doesn't support Mp3PRO)
Songs:
"Mother Earth" by Within Temptation (Orchestral Gothic Metal)
"Wax & Wane" by Cocteau Twins (Gothic)
"Ophelia" by The Tear Garden (semi-industrial, heavy beat)
The Experiment:
I downloaded "Ophelia" and "Wax & Wane" from an MP3 site (I paid for them!), which encoded them at 192kbps using LAME. I encoded "Mother Earth" from a CD using MusicMatch Jukebox, at both 192kbps MP3 and 96kbps Mp3PRO. Using JetAudio, I converted the downloaded MP3's to 96kbps MP3PRO. As predicted, the MP3Pro files were about 50% of the size of the MP3 files.
I started up VirtualDJ, and for each song, I cued up the same song on both decks, the MP3 file on one deck, and the MP3Pro file on the other. I synced them up and started playing them at the same time. Fading from one to the other, I tried to listen intently for every little difference or inconsistency that I could. It should probably be noted that the waveforms didn't line up perfectly, but were extremely close. Inasmuch as I could be biased, I had 2 other people (another DJ and a singer) listen to the samples and try to determine first, if they could tell the difference between the two samples, and if they could, which had the better quality. I did both gradual "automix" fades and instant fades.
Results: In the case of "Ophelia" and "Wax & Wane," none of the three of us could hear an audible difference between the two samples. With "Ophelia," one person guessed incorrectly which one they thought had the worse quality. With "Mother Earth," No one else could hear a difference, but I could hear what I would describe as a "brassy" quality to the MP3PRO file, but only at the beginning.
Conclusion: if the sound quality in this setup is indistinguishable over very good headphones, the sound quality should be perfectly fine for the vast majority of club settings. Granted, this is a bit unscientific, and if anyone can find a flaw in my reasoning, please let me know. It might be that VDJ is Just. That. Damn. Good, and it can make crappy MP3's sound divine. But, what I really think it is, is that people make too big a deal bout MP3 "quality." I'd still like VDJ to release an MP3PRO plugin, though.
Däch
http://www.closedcaskets.com/
Tools:
Generic P4 2.8GHz, 512DDR, 60GB 5400RPM, DVD-R, crappy internal sound card
M-Audio Transit USB
Sony MDR-V500 headphones
Software:
Jet Audio 6.0.4
MusicMatch Jukebox 9.0
VirtualDJ 2.02 (Yes, I realize VDJ doesn't support Mp3PRO)
Songs:
"Mother Earth" by Within Temptation (Orchestral Gothic Metal)
"Wax & Wane" by Cocteau Twins (Gothic)
"Ophelia" by The Tear Garden (semi-industrial, heavy beat)
The Experiment:
I downloaded "Ophelia" and "Wax & Wane" from an MP3 site (I paid for them!), which encoded them at 192kbps using LAME. I encoded "Mother Earth" from a CD using MusicMatch Jukebox, at both 192kbps MP3 and 96kbps Mp3PRO. Using JetAudio, I converted the downloaded MP3's to 96kbps MP3PRO. As predicted, the MP3Pro files were about 50% of the size of the MP3 files.
I started up VirtualDJ, and for each song, I cued up the same song on both decks, the MP3 file on one deck, and the MP3Pro file on the other. I synced them up and started playing them at the same time. Fading from one to the other, I tried to listen intently for every little difference or inconsistency that I could. It should probably be noted that the waveforms didn't line up perfectly, but were extremely close. Inasmuch as I could be biased, I had 2 other people (another DJ and a singer) listen to the samples and try to determine first, if they could tell the difference between the two samples, and if they could, which had the better quality. I did both gradual "automix" fades and instant fades.
Results: In the case of "Ophelia" and "Wax & Wane," none of the three of us could hear an audible difference between the two samples. With "Ophelia," one person guessed incorrectly which one they thought had the worse quality. With "Mother Earth," No one else could hear a difference, but I could hear what I would describe as a "brassy" quality to the MP3PRO file, but only at the beginning.
Conclusion: if the sound quality in this setup is indistinguishable over very good headphones, the sound quality should be perfectly fine for the vast majority of club settings. Granted, this is a bit unscientific, and if anyone can find a flaw in my reasoning, please let me know. It might be that VDJ is Just. That. Damn. Good, and it can make crappy MP3's sound divine. But, what I really think it is, is that people make too big a deal bout MP3 "quality." I'd still like VDJ to release an MP3PRO plugin, though.
Däch
http://www.closedcaskets.com/
发表时间 Thu 23 Sep 04 @ 7:37 am
Rune (DJ-In-Norway)
"But, what I really think it is, is that people make too big a deal bout MP3 quality"
true! ;) most mp3's are fine, and for a club enviroment (often pa systems far from hi-fi, and even mono sound) a mp3 at a low bitrate might sound fine ;)
BUT - if you are an audiophile there are small differences in dynamics, in crisp high sounds etc. mp3pro does a good job (its mp3 encoding at variable bitrate, and I recommend that).
But some say that musicmatch have a bad encoder, maybe they improved themself? havent used it for years...
also, VDJ have the LAME encoder, by most people seen as the #1 mp3 encoder in the world ;) so.. yeah... VDJ do have a good sound...
what u need to to for those experiments is compare an encoded mp3 file to the original file at a CD. Bring your friends in, and try a new experiment - compare mp3s to cd's ;) I have found that 160-192kbps with VBR gives a perfect result, having the same dynamics and crisp sound as the original on cd... ;) But for club-use you can for sure encode at less bitrate if you want....
but all in all, I agree with you... there are far to much fuzz about mp3 quality. Most sound just fine.... ;)
dj in norway
true! ;) most mp3's are fine, and for a club enviroment (often pa systems far from hi-fi, and even mono sound) a mp3 at a low bitrate might sound fine ;)
BUT - if you are an audiophile there are small differences in dynamics, in crisp high sounds etc. mp3pro does a good job (its mp3 encoding at variable bitrate, and I recommend that).
But some say that musicmatch have a bad encoder, maybe they improved themself? havent used it for years...
also, VDJ have the LAME encoder, by most people seen as the #1 mp3 encoder in the world ;) so.. yeah... VDJ do have a good sound...
what u need to to for those experiments is compare an encoded mp3 file to the original file at a CD. Bring your friends in, and try a new experiment - compare mp3s to cd's ;) I have found that 160-192kbps with VBR gives a perfect result, having the same dynamics and crisp sound as the original on cd... ;) But for club-use you can for sure encode at less bitrate if you want....
but all in all, I agree with you... there are far to much fuzz about mp3 quality. Most sound just fine.... ;)
dj in norway
发表时间 Thu 23 Sep 04 @ 1:05 pm
amazingsounds
I did my own experiments with different bit rates a few months ago (just using AudioEdit and Windows Media Player).
I did this at a venue (banquet hall) I perform at regularly with full speakers (I use JBL Eon15's and Eon Subs) at a moderate volume level. I never like to play too loud. :)
Here's what I found:
At 256 none of us (there were 5) could tell the difference between the original CD and 256. One person thought the 256 sounded better.
At 192, again we could not tell the difference.
At 128 - Three of us noticed "something different" - I thought it sounded 'tinny' and the other two said it seemed to be a bit 'noisier' sounding.
At 96 there was a very distinctive difference (from the CD as well as from 192) but we could hardly tell the difference going from 128 to 96. But at 96 we could ALL tell there was a difference.
The biggest reason you want to have good QUALITY in both the music AND your speakers (as in not old worn out, over powered, etc.) is the FATIGUE factor. People will get 'tired' or fatigued from music which is not played properly (even improper EQ settings) which will cause them not to want to dance as much and/or to think negatively about their experience.
So, I decided then and there that all my music would be at 192 minimum!
I must confess to being unfamiliar with MP3'PRO' however and therefore my experiments did not include that 'type' of file.
But if you are going to experiment, you should do it in a REAL setting (not at home and surely not with HEADPHONES) to see how the sound travels and sounds over the entire venue.
DJAlan
I did this at a venue (banquet hall) I perform at regularly with full speakers (I use JBL Eon15's and Eon Subs) at a moderate volume level. I never like to play too loud. :)
Here's what I found:
At 256 none of us (there were 5) could tell the difference between the original CD and 256. One person thought the 256 sounded better.
At 192, again we could not tell the difference.
At 128 - Three of us noticed "something different" - I thought it sounded 'tinny' and the other two said it seemed to be a bit 'noisier' sounding.
At 96 there was a very distinctive difference (from the CD as well as from 192) but we could hardly tell the difference going from 128 to 96. But at 96 we could ALL tell there was a difference.
The biggest reason you want to have good QUALITY in both the music AND your speakers (as in not old worn out, over powered, etc.) is the FATIGUE factor. People will get 'tired' or fatigued from music which is not played properly (even improper EQ settings) which will cause them not to want to dance as much and/or to think negatively about their experience.
So, I decided then and there that all my music would be at 192 minimum!
I must confess to being unfamiliar with MP3'PRO' however and therefore my experiments did not include that 'type' of file.
But if you are going to experiment, you should do it in a REAL setting (not at home and surely not with HEADPHONES) to see how the sound travels and sounds over the entire venue.
DJAlan
发表时间 Thu 23 Sep 04 @ 4:00 pm
Dach
I wish I had a venue I could try this out at beforehand. I am, however, just starting out, and there are not a lot of places for an upstart goth DJ to ply his trade. There are FAR more goth DJ's than clubs here in LA. My logic with using headphones was that it would more closely approximate a really good club sound system than would any speakers I could easily plug into my laptop.
Däch
http://www.closedcaskets.com/
Däch
http://www.closedcaskets.com/
发表时间 Thu 23 Sep 04 @ 7:38 pm
djbambi
Unfortunately with headphones you won't be able to hear "muddy bass" defects as well as with a good set of speakers.
However with headphones you'll be able to detect low-bitrates "artifacts" in the mid-to-high-frequency range better, and realize that less-than-128kbps mp3s are not acceptable.
I use studio reference monitors in my home setup (JBL 4208) with a good amp (Hafler TransNova), and I know that when stuff sounds good on them, it'll sound good pretty much everywhere.
IMHO, the ideal mp3 bitrate is 160Kbps for vinyl encoding (have a great stylus! it'll only sound as good as the weakest link in the recording chain), and 192Kbps for CD encoding. Anything over that is overkill, and anything under is too risky.
Nicolas
However with headphones you'll be able to detect low-bitrates "artifacts" in the mid-to-high-frequency range better, and realize that less-than-128kbps mp3s are not acceptable.
I use studio reference monitors in my home setup (JBL 4208) with a good amp (Hafler TransNova), and I know that when stuff sounds good on them, it'll sound good pretty much everywhere.
IMHO, the ideal mp3 bitrate is 160Kbps for vinyl encoding (have a great stylus! it'll only sound as good as the weakest link in the recording chain), and 192Kbps for CD encoding. Anything over that is overkill, and anything under is too risky.
Nicolas
发表时间 Thu 23 Sep 04 @ 8:38 pm
vantinedj
I rip at 128 and bought a BBE sonic maximizer. It really boosts the sound and you cannot tell the difference at all between a cd and mp3 (except for the occasional bad rip). If works well for the mobile dj such as myself.
Here is what they look like:
http://www.americanmusical.com/item--i-BBE-882I--src-D0301DT0HAMS0000.html
Here is what they look like:
http://www.americanmusical.com/item--i-BBE-882I--src-D0301DT0HAMS0000.html
发表时间 Fri 24 Sep 04 @ 12:25 am
Dach
I had a thought that maybe my Transit was cleaning up the sound a bit. I don't know for sure. Although, for the price of that BBE unit, I could just buy a huge external HDD and rip everything at 320k or something.
发表时间 Fri 24 Sep 04 @ 8:45 am
sambukashot
I started out with 160 but soon reliased it's a waste of time. The best results are at 256, i work with large sound systems in clubs (30K) and you can tell the difference, the lowest rate i would use is 192.
发表时间 Fri 24 Sep 04 @ 9:27 am
bagpuss
I use CD-ex to encode, with VBR, and with this you can specify the minimum bitrate and the maximum, so it uses a higher quality when needed and lower on times of silence or quiet less complicated parts...
I use 128kbps - 320 kbps,
With this a 6 minute mp3 would typically be around 8 megs,
The sound is perfect and probably better than 192 at fixed bit rate...
The encoder you use most important, then look at a minimum "fixed" bitrate of 160kbps and mazimum of 220kbps, I would reccomend you use 220, as external harddrives are getting bigger and cheaper all the time...
but music isn't getting longer...., so it makes sense.
Don't make the big mistake of useing the wrong encoder and at a too poor bit rate..., else you'll be faced with the long proccess of doing it all again...
I use 128kbps - 320 kbps,
With this a 6 minute mp3 would typically be around 8 megs,
The sound is perfect and probably better than 192 at fixed bit rate...
The encoder you use most important, then look at a minimum "fixed" bitrate of 160kbps and mazimum of 220kbps, I would reccomend you use 220, as external harddrives are getting bigger and cheaper all the time...
but music isn't getting longer...., so it makes sense.
Don't make the big mistake of useing the wrong encoder and at a too poor bit rate..., else you'll be faced with the long proccess of doing it all again...
发表时间 Fri 24 Sep 04 @ 1:01 pm
Rune (DJ-In-Norway)
mp3pro is just mp3 encoding at variable bitrate...
as bagpuss said, variable bitrate will give higher bitrates to complex areas of the song, and less bitrate to more quiet part of the song... hence give a BETTER overall result.
And some encoders using LAME, like CD-ex, can let you specify what the lowest and highest bitrate for VBR encoding should be.... like setting it to 128 at lowest, 320 at highest.
Or other encoders will let you set it to 192 average...
it gives a PERFECT result ;)
and agree... 192 is the best setting... anything above is kinda overkill, anything less is not good... :)
as bagpuss said, variable bitrate will give higher bitrates to complex areas of the song, and less bitrate to more quiet part of the song... hence give a BETTER overall result.
And some encoders using LAME, like CD-ex, can let you specify what the lowest and highest bitrate for VBR encoding should be.... like setting it to 128 at lowest, 320 at highest.
Or other encoders will let you set it to 192 average...
it gives a PERFECT result ;)
and agree... 192 is the best setting... anything above is kinda overkill, anything less is not good... :)
发表时间 Fri 24 Sep 04 @ 1:49 pm
Dach
With all due respect, MP3PRO is definitely not MP3 with a variable bitrate. MP3PRO splits the signal into 2 paths, 1 encoded and 1 synthesized. Since typically all sounds above 10KHz are harmonics of sounds below 10KHz, those parts are synthesized by the codec. Consequently, a 96kbps MP3PRO file should (and in my testing with MP3PRO compatible players, does) be identical in sound quality to a 192kbbps MP3. An incredibly detailed explantion of how MP3PRO works can be found at http://www.digit-life.com/articles/mp3pro/. This page was part of the reason I decided to go with MP3PRO in the first place. All the quality, half the space.
Däch
http://www.closedcaskets.com/
Däch
http://www.closedcaskets.com/
发表时间 Fri 24 Sep 04 @ 7:17 pm
bagpuss
Yes their are many different encoding formats for music, the original mp3 is obviously the most popular, beware of some though as there are differences...
Usually slight but still differences, for now i'm more than happy with plain old mp3...
Usually slight but still differences, for now i'm more than happy with plain old mp3...
发表时间 Fri 24 Sep 04 @ 10:20 pm
Rune (DJ-In-Norway)
@DACH
sorry, my bad... :)
MP3pro is for sure MP3 encoding with SBR, and not VBR (sorry, my bad...lol)
MP3PRO is an extended MP3 version that uses SBR for increasing the efficiency of this codec for low bitrates.
SBR means "Spectral Band Replication" and is used with AAC (called aacPlus or AAC+ then) or MP3 (then called mp3PRO) to increase the coding efficiency of these standard codecs, but only for low bitrates around 20-64 kbps for AAC and 32-96 kbps for mp3PRO, as it will not help for higher bitrates when the codecs have sufficient headroom to encode the high frequencies without SBR.
THEREFORE mp3pro is for LOW encoding ONLY, to make those files sound better.... and a choice if you want to save space.
But 192kbps with VBR sounds a lot better (encoding at 320 for complex areas of song, 128 at quiet part)
So, again, encoding with VBR (variable bit rate) at 192kbps average is the best.... ;) acording to many many many audiophile users all over the world...
but mp3pro is a good choice if you want to save space... keeping filesize lower. Not tested myself, but are said to not have the dynamics and quality of a mp3 encoded at 192 vbr... as stated above..
;)
sorry, my bad... :)
MP3pro is for sure MP3 encoding with SBR, and not VBR (sorry, my bad...lol)
MP3PRO is an extended MP3 version that uses SBR for increasing the efficiency of this codec for low bitrates.
SBR means "Spectral Band Replication" and is used with AAC (called aacPlus or AAC+ then) or MP3 (then called mp3PRO) to increase the coding efficiency of these standard codecs, but only for low bitrates around 20-64 kbps for AAC and 32-96 kbps for mp3PRO, as it will not help for higher bitrates when the codecs have sufficient headroom to encode the high frequencies without SBR.
THEREFORE mp3pro is for LOW encoding ONLY, to make those files sound better.... and a choice if you want to save space.
But 192kbps with VBR sounds a lot better (encoding at 320 for complex areas of song, 128 at quiet part)
So, again, encoding with VBR (variable bit rate) at 192kbps average is the best.... ;) acording to many many many audiophile users all over the world...
but mp3pro is a good choice if you want to save space... keeping filesize lower. Not tested myself, but are said to not have the dynamics and quality of a mp3 encoded at 192 vbr... as stated above..
;)
发表时间 Mon 27 Sep 04 @ 1:51 pm