Audio File Storage Formats

[Tungsten Gruvsten]

Here's some that i've used:

Ginger Baker Trio - Going Back Home

-'Rambler' on here is very lush and the ride and splash cymbal hits are unbelievably clean and present.

King Crimson - Larks Tongues in Aspic

-Listen to part one, the percussion at the very start and the buzz saw guitar that comes in have very strong overtones. The main heavy part is a bit too distorted to be of any use.

Tortoise - S/T

-John McEntire's purist analog recording traditions make this album an excellent test of anything audio...no digital anything on this album save for the transfer during mastering.

Cymbals, vibes, tons of high end info all over the entire album.

Red House Painters - Songs for a Blue Guitar

This is a recording masterpiece-The one i take to demo speakers and rooms i'm not familiar with. It just has everything. If you are going to use it for a test, at least listen to it for it's beauty as well. The pedal steel and background harmoniesin "Song for a Blue Guitar" is goosebump-inducing. The acoustic guitar in 'Priest Alley Song', the big reverbed out vocals on 'All Mixed Up' (blows away the cars original!!) Everyone should know this album!

Hmmm ones you might have...

Floyd - Meddle - pay attention to the acoustic guitar strums during Fearless

Peter Gabriel - Us

"Come Talk To Me" is a very lush Gabriel production, lots to listen for here.

Neil Young - Harvest

"Out on the Weekend" is sparse in arrrangement, but you can hear the effects of the room it was recorded in...

And for Steve

David Bowie - Space Oddity

Listen to the 12-string and voice reverb in 'Letter to Hermione' - a second acoustic comes in with a wide stereo spread-use this to check for sound field definition. Also for stereo separation check out 'Cygnet Committee' - there should only be the tiniest bit of kick drum (and the odd snare hit for effect) in the left channel and if you listen to only the left channel you can really pick out some definition between Bowie's vocals, the killer vox guitar tone and the organ(farfisa maybe?)

Also the end of 'God Knows I'm Good' has some groovy 12 string and multi-tracked acoustic guitar bits to check out...only about :30 sec though.

And here's the ultimate ones:

Glenn Gould: Bach Variations (Sony Super Bit Mapping version)

-you should be able to crank this, and still here glenn gould humming a little bit during the quiet passages.

Vladimir Horowitz - The Last Recording(Sony Super Bit Mapping version)

The dynamics on this are huge-no compressors or anything in the signal path when recorded. Pay special attention to the low chords in Haydn's "Adagio e cantabile"

I'd also suggest pretty well any Rudy Van Gelder recorded Blue Note stuff-he was a master.

Now, make sure the test is double blind, even put a couple different bit rates(160, 192, 256,320 as well as VBR) in there with the original wav file and try a wav file with a 22k cutoff...make their ears work for it...

sorry bout that rant....i'm bored...

[\/\/illy]

Hey Tungsten! Great input! Thanks so much. I've got some Crimson around (Bible Black?) and some Giger Baker (with Fela Ketu) but not the specific albums that you've mentioned. Meddle was one of the first things I transferred for this test. I also ripped Animals while I was at it. I've got a great Fela album (Both Sides: Jazz & Dance) that I think i'll throw into the mix.

Just to confirm that last part you wrote: You're suggesting that I listen to a song in more than two formats right?

I guess to be fair I need to play both the MP3 and the CD through the same computer connected to my stereo right? If I use my CD player for the CD and the computer for the MP3, that's not really fair is it? My computer connects to my stereo through a digital optical cable. I wonder if the CD-ROM drive is going to pass through DAC and then ADC before it gets passed off to the stereo or it'll stay digital all the way to the DACs in the stereo?

[Tungsten Gruvsten]

quote:

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Originally posted by \/\/illy:

[QB]

Just to confirm that last part you wrote: You're suggesting that I listen to a song in more than two formats right?

...I guess to be fair I need to play both the MP3 and the CD through the same computer connected to my stereo right?

[QB]

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For sure. Rip the same file at 192, 256 and 320kbps mp3's. For the original file, rip a wav file(rip it from the CD using EAC without compression) to include with the mp3's. This way all files are playing off the harddrive, through the digital cable, then one D>A conversion at the receiver.

Fromt the Skeptics Dictionary:

"A double-blind test is a control group test where neither the evaluator nor the subject knows which items are controls. A random test is one which randomly assigns items to the control or experimental groups.

The purpose of controls, double-blind and random testing is to reduce error, self-deception and bias. An example should clarify the necessity of these safeguards. "

http://skepdic.com/control.html

Sooo.... that being said:

Rip all the files to a directory. Give them all letters or numbers for filenames-something arbitrary.

Since Winamp will display the kbps of any file, you can use it to determine afterward which is which. (768kbps is a wave file)

Make sure no one can see the Computer to determine which is which. Have someone not involved drag all the files into the winamp playlist randomly, this person not knowing what is what either.

Give the listener(s) a sheet of paper and as the tracks are played have them write down if it's an mp3 or original. Listen to them all, either total songs or bits, having someone available to skip tracks.

Do the entire test twice and mix up the order of the songs each time - There is no need to play wav/mp3 versions of the same file back to back, maybe do that as a separate test to see if you can detect a difference between the two.

Get a little bit inebriated and try it again...maybe start a hypothesis on mp3 recognition and sobriety....hehehe

good luck!