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Endeavor
Hi All,
I'm taking a deeper dive into the digital audio realm and have learned a lot from reading through the info on this board over the past couple of weeks.
So I downloaded EAC and LAME 3.90.3 per the recommendations to increase the quality of my MP3's vs what MusicMatch is currently giving me. Everything installed fine and is up and running.

I noticed the MP3's (APS) seem a little brighter (more high end) than the CD's do when played on my computer. I thought maybe LAME was overemphasizing the high-end, but that didn't seem to make sense based on what I'd read.
So then I used EAC/LAME to generate a WAV file so I could compare the WAV to the MP3. Well, the MP3 sounds very close to the WAV (played through WINAMP) in terms of overall EQ, just relatively minor differences.
So the question is, what would account for the difference in high end between the EAC generated files, and the original source CD? It seems like it must be isolated to the CD drive (Samsung SM-348B). Does the drive do the D/A conversion or is that done somewhere else?
Thanks for your help,
Bill
echo
And how does the wav file sound to you in comparison with the CD? You might want to read some of the FAQ's here first and do a little search on "placebo effect".

Anyway... try disabling all EQ from your audio player.
VCSkier
you might want to look into an abx test so you can really see the differences in what you can really hear. all of us are subject to the placebo effect. foobar2000 is the easiest way to do an abx that i know of. with equalizers and whatnot turned off, wav and cd will be exactly identical. mp3 aps will probably sound identical to you, but it is lossy, meaning that it will lose some quality from the original (wav).

edit: and yeah, you were right, lame will not intentionally "overemphasize" high end. countless hours have been put into lame sounding as close to the original as possible.
Lyx
Depending on how cd-audio is played back on your system, it can be that the CD-audiopipeline of your soundcard "colors" the sound. This for example is the case with my soundcard: all CDs played back directly on my PC sound different(much more treble, less low-freqs) compared to any other sound generated by the soundcard.

Try ABXing WAV vs. MP3. Comparing CD-Audio directly with MP3 has too many sources of error.

- Lyx
VCSkier
QUOTE(VCSkier @ Mar 27 2005, 06:22 PM)
with equalizers and whatnot turned off, wav and cd will be exactly identical.
*




QUOTE(Lyx @ Mar 27 2005, 06:30 PM)
Depending on how cd-audio is played back on your system, it can be that the CD-audiopipeline of your soundcard "colors" the sound. This for example is the case with my soundcard: all CDs played back directly on my PC sound different(much more treble, less low-freqs) compared to any other sound generated by the soundcard.

Try ABXing WAV vs. MP3. Comparing CD-Audio directly with MP3 has too many sources of error.

- Lyx
*



i stand corrected. i was unaware that playing directly from cd's did this.
Lyx
It isn't always the case - depends on soundcard and the way audio is extracted for playback. But its one potential error-source which can easily be excluded.

- Lyx
kjoonlee
Lyx, does that mean you don't use DAE for CD playback?
Cosmo
Do you have an analog connection from your drive to your sound card?
Make sure you're using digital...
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I always physically disconnect the analog wires, just to be sure it's never used.
Vietfobster
lol cd vs wav blink.gif
unfortunateson
Winamp changes its EQ behavior on different file types, so thats probably why you hear differences between a wave and mp3 file.
Endeavor
QUOTE
Do you have an analog connection from your drive to your sound card?
Make sure you're using digital...
I always physically disconnect the analog wires, just to be sure it's never used.

Thanks - I double checked that and the cd drives are only connected to the i/o controller, no analog connections.

QUOTE
Depending on how cd-audio is played back on your system, it can be that the CD-audiopipeline of your soundcard "colors" the sound. This for example is the case with my soundcard: all CDs played back directly on my PC sound different(much more treble, less low-freqs) compared to any other sound generated by the soundcard.

Try ABXing WAV vs. MP3. Comparing CD-Audio directly with MP3 has too many sources of error.

That's what I was wondering about. I guess it depends on the sound card. Your post DID prompt me to look at the soundcard settings and lo and behold, the CD Audio volume setting on the Soundblaster mixer was set a few db lower than the WAV volume. Once I set them the same I couldn't hear any real difference. Distortion?, soundcard being pushed a little harder? Who knows, but it corrected the problem.

QUOTE
you might want to look into an abx test so you can really see the differences in what you can really hear. all of us are subject to the placebo effect. foobar2000 is the easiest way to do an abx that i know of. with equalizers and whatnot turned off, wav and cd will be exactly identical. mp3 aps will probably sound identical to you, but it is lossy, meaning that it will lose some quality from the original (wav).

Cool software, but I was a musician for years and logged hundreds of hours in studios. No software is going to tell me I'm hearing things. wink.gif And Foobar proved it, I was right! (50% of the time). rolleyes.gif lol
That was a humbling experience, but that was through these mid-level PC speakers. I'll try it again with headphones just as an experiment to see if I can hear a difference. Thanks for the tip on Foobar.

Thanks everyone for the help and suggestions.
VCSkier
QUOTE(Endeavor @ Mar 28 2005, 12:22 AM)
I'll try it again with headphones just as an experiment to see if I can hear a difference.
*


yeah, headphones should help. abxing is alot easier w/ them.
dreamliner77
QUOTE(Endeavor @ Mar 27 2005, 11:22 PM)
QUOTE
you might want to look into an abx test so you can really see the differences in what you can really hear. all of us are subject to the placebo effect. foobar2000 is the easiest way to do an abx that i know of. with equalizers and whatnot turned off, wav and cd will be exactly identical. mp3 aps will probably sound identical to you, but it is lossy, meaning that it will lose some quality from the original (wav).

Cool software, but I was a musician for years and logged hundreds of hours in studios. No software is going to tell me I'm hearing things. wink.gif And Foobar proved it, I was right! (50% of the time). rolleyes.gif lol
That was a humbling experience, but that was through these mid-level PC speakers. I'll try it again with headphones just as an experiment to see if I can hear a difference. Thanks for the tip on Foobar.
*




ABX tests are normally most humbling for musicians and studio-meisters (trust me, I'm one myself).
DonP
QUOTE(dreamliner77 @ Mar 28 2005, 12:38 AM)

ABX tests are normally most humbling for musicians and studio-meisters (trust me, I'm one myself).
*



Maybe it's just what I look for in music, but in some ways ABX has the opposite effect on me. Many things I can distinguish in ABX I could never catch by just hearing B, so I don't fret about it. Just the opposite of hearing differences that vanish under the revealing light of blind comparison.
Lyx
QUOTE(kjoonlee @ Mar 28 2005, 01:40 AM)
Lyx, does that mean you don't use DAE for CD playback?
*


Exactly. I never bothered to correct it after i got a new drive, since i rip my CDs and play them from HDD anyways.

@Endeavor:
ABX-testing is a bit more sensitive to the slightest errors in the test-procedure than it seems at first. Even the slightest volume-difference, an enabled EQ, a slight gap at the beginning of one file but not the other, or comparing analogue-output vs. digital-output can distort the test-results(notice that it isn't really the difference between an analogue-signal and a digital-signal which can distort the result but instead that depending on the in/output differet circuits and chips on the soundcard may be used - which in turn may be of varrying quality).

- Lyx
Endeavor
QUOTE
@Endeavor:
ABX-testing is a bit more sensitive to the slightest errors in the test-procedure than it seems at first. Even the slightest volume-difference, an enabled EQ, a slight gap at the beginning of one file but not the other, or comparing analogue-output vs. digital-output can distort the test-results(notice that it isn't really the difference between an analogue-signal and a digital-signal which can distort the result but instead that depending on the in/output differet circuits and chips on the soundcard may be used - which in turn may be of varrying quality).


Yes, once we started discussing different signal paths, it hit me that anything different in the signal path has the potential to color the sound, even a simple volume control, not to mention what you stated about chipsets of varying quality, or circuits tuned for different sources.

Thanks for your time and help,
Bill

Lyx
QUOTE(Endeavor @ Mar 29 2005, 12:34 AM)
Yes, once we started discussing different signal paths, it hit me that anything different in the signal path has the potential to color the sound, even a simple volume control, not to mention what you stated about chipsets of varying quality, or circuits tuned for different sources.
*



Well, if one thinks of it, its a quite funny situation. On one side, we tend to overestimate our own hearing by leaps and bounds - especially on boards like this(and dont get me started on those "audiophile"-circles). But on the other hand, it seems that we're able to pick up very minor differences subconsciously - and then maybe amplify and transform them by placebo(i.e. a tiny gap at the beginning of a file could make us detect a difference in ABX, but we cannot find out what it is, overstress our concentratrion, and then placebo kicks in and makes us falsely blame it on "there was a tiny bit of smearing noticable"). Of course, this is all stuff which we dont notice and care about during normal listening - because then we focus on other things. But when the goal is only to detect a difference, then things become apparent which we usually dont care about - forget noticing 18khz-content in music... a 80ms gap at the beginning of a sample, or a minor volume difference, is way more apparent :)

QUOTE(Endeavor @ Mar 29 2005, 12:34 AM)
Thanks for your time and help,
Bill
*


You're welcome,

- Lyx
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