The Effects of MP3 Compression on Perceived Emotional Characteristics in Musical Instruments

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Err
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The Effects of MP3 Compression on Perceived Emotional Characteristics in Musical Instruments

Post by Err »

Clickbait title here: http://www.avclub.com/article/vinyl-sno ... -le-246959

This showed up on my Facebook feed so I took the bait. However, after reading the actual study here:

http://www.aes.org/e-lib/browse.cfm?elib=18523

you'll see that their methods were essentially BS to give the results they wanted.

Abstract:
Musical instrument sounds have distinct timbral and emotional characteristics that can change when audio processing is applied. This paper investigates the effects of MP3 compression on the emotional characteristics of eight sustained instrument sounds using listening tests. The experimental paradigm involved a pairwise comparison of compressed and uncompressed samples at several bit rates over ten emotional categories. The results showed that MP3 compression strengthened neutral and negative emotional characteristics such as Mysterious, Shy, Scary, and Sad, and weakened positive emotional characteristics such as Happy, Heroic, Romantic, Comic, and Calm. Angry was relatively unaffected by MP3 compression, probably because the background “growl” artifacts added by MP3 compression decreased positive emotional characteristics and increased negative characteristics such as Mysterious and Scary. Compression effected some instruments more and others less; trumpet was the most effected and the horn the least.
However, they only tested up to 112K bitrate. See table 2: http://www.aes.org/e-lib/download.cfm/1 ... f?ID=18523

Full disclosure, I don't care for the MP3 format mainly due to how it can't do true gapless playback. You'll only notice this if continuous music is split into tracks. While I listen to flac format, I'd be hard pressed to tell the difference between a 256 to 320 Kbs MP3 and lossless in most cases. When you get into 198 and lower MP3 territory, I can start hearing discrepancies in the upper range such as cymbals. Low volume sections of music are also handled poorly in lower rate MP3. The worst offender I've heard was The Door's Riders on the Storm. At the beginning where you should be able to hear a bit of low tape hiss that's present on the CD or Vinyl, you hear the lower bitrate MP3 try to suppress the hiss and the result is a glassy-sounding, weak organ. A 256+ MP3 won't do this if the encoding was done well.

In my opinion, this study didn't go far enough in their testing. The bitrates they used should've been the controls as they knew going into this that instruments would sound bad. 128, 156,198, 256, and 320 should've also been included. I can almost guarantee that at some point the emotional response to the instruments change. Also, lossless encoded at lower bitrates should give the same result. Poor encoding is poor encoding and it's not inherent to any certain format.
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FlyingPenguin
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Re: The Effects of MP3 Compression on Perceived Emotional Characteristics in Musical Instruments

Post by FlyingPenguin »

I have to admit tbat even at 320 cymbals sound like crap to me. Compression just messes up cymbals. I really don't notice compression artifacts any other time unless there's a drum solo. Then the crappy cymbals stand out.

Then again, I'm a former sound engineer and tend to notice things most people don't. Like I hate how so many tracks today are over driven to distortion.

All that said, I'm no fanatic and MP3 is fine for me. I just won't use VBR if I encode them myself.

For a long time we all listened to music on crappy 8 tracks and we were happy. Our parents listened to all their music on AM radio and they were happy.

Most people have satellite radio and they REALLY compress the crap out of it. It's aweful to me - far worse than a 128 Kbit MP3 IMO, and yet people are happy with it.
"Turns out I’m 'woke.' All along, I thought I was just compassionate, kind, and good at history. "

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Re: The Effects of MP3 Compression on Perceived Emotional Characteristics in Musical Instruments

Post by Pugsley »

FlyingPenguin wrote:I have to admit tbat even at 320 cymbals sound like crap to me. Compression just messes up cymbals. I really don't notice compression artifacts any other time unless there's a drum solo. Then the crappy cymbals stand out.

Like I hate how so many tracks today are over driven to distortion.
I used to do Live PA work back in the day and mostly ran monitors but on occasion ran FOH. I too hate all the clipping in shit now. RHCP is dead to me now. I LOVE their music but cant stand listening to it. That's why i still enjoy Dark side of the moon. Why can't we have more engineers like Alan Parsons.

Some of the EDM people know more about mastering then so called engineers. Deadmau5 comes to mind. Love his stuff.
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Re: The Effects of MP3 Compression on Perceived Emotional Characteristics in Musical Instruments

Post by FlyingPenguin »

I did a LOT of monitor mixes back in the day. I found that a lot more interesting (and challenging) than PA mixing.

I did monitor mix for Sarah Vaughn at Gusman Cultural Center in Miami just a few months before she died. Sweet lady and she complimented me highly because - unlike a lot of monitor mix sound engineers - once I got the mix right around the 3rd or 4th song I LEFT THE BOARD ALONE unless one of the performers gave me a hand signal.

I never felt the need to fiddle with things just to look busy, and artists appreciated that. If you do your job right during dress rehearsal, everything should be close except for overall levels which generally need to go up during the performance. Sometimes someone needs to hear some more drums, or (more often) a lot less guitar.
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Re: The Effects of MP3 Compression on Perceived Emotional Characteristics in Musical Instruments

Post by Losbot »

I look for FLAC copies since my car will play them, as well as MP3.
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