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  #21  
Old 10-21-2011, 04:25 PM
Celestial Being Celestial Being is offline
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u

Last edited by Celestial Being; 10-22-2011 at 03:42 PM.
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  #22  
Old 10-21-2011, 04:35 PM
skip252 skip252 is offline
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Time Out!

A big heads up about ABi. If you don't want inaccuracies discussed then don't post them. What you are posting is contrary to what's established as the standard for testing lossy encoding. If you can't respond in the same respectful manner the questions are being posed it's better that you don't respond at all. Calling other members names like troll won't be tolerated.

Last edited by skip252; 10-21-2011 at 04:54 PM.
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  #23  
Old 10-21-2011, 04:50 PM
Celestial Being Celestial Being is offline
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!

Last edited by Celestial Being; 10-22-2011 at 03:43 PM.
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  #24  
Old 10-21-2011, 05:35 PM
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I don't think it's important if your 15 or 35, Enigmatic makes a very valid point if you don't abx you'll never know for sure, but hey that's up to you. Just don't make claims without testing as those are false IMHO. BTW I didn't read anything malicious on his part, rather it’s sound advice. BTW just because you can hear the mosquito ring doesn't necessarily mean that you can tell the difference between a properly encoded file and another done at a much higher bit rate.
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  #25  
Old 10-21-2011, 06:03 PM
Enigmatic Enigmatic is offline
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Quote:
Originally Posted by Celestial Being View Post
They "probably" (a phrase you used ALOT in your posts) can't hear the difference(s), because of presbycusis.
Probably because it depends on things like the listener and the music. They cannot hear a difference, because there is no difference that can be heard.
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I don't put ABX testing on a pedestal like you do.
http://www.theaudiocritic.com/downloads/article_1.pdf:
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Regular readers of this publication know how to refute the various lies invoked by the high-end cultists in opposition to double-blind listening tests at matched levels (ABX testing), but a brief overview is in order here.
Quote:
The ABX methodology requires device A and device B to be level-matched within ±0.1 dB, after which you can listen to fully identified A and fully identified B for as long as you like. If you then think they sound different, you are asked to identify X, which may be either A or B (as determined by a double-blind randomization process). You are allowed to make an A/X or B/X comparison at any time, as many times as you like, to decide whether X=A or X=B. Since sheer guessing will yield the correct answer 50% of the time, a minimum of 12 trials is needed for statistical validity (16 is better, 20 better yet). There is no better way to determine scientifically whether you are just claiming to hear a difference or can actually hear one.

The tweako cultists will tell you that ABX tests are completely invalid. Everybody knows that a Krell sounds better than a Pioneer, so if they are indistinguishable from each other in an ABX test, then the ABX method is all wet—that’s their logic. Everybody knows that Joe is taller than Mike, so if they both measure exactly 5 feet 11 1⁄4 inches, then there is something wrong with the Stanley tape measure, right?

The standard tweako objections to ABX tests are too much pressure (as in “let’s see how well you really hear”), too little time (as in “get on with it, we need to do 16 trials”), too many devices inserted in the signal path (viz., relays, switches, attenuators, etc.), and of course assorted psychobabble on the subject of aural perception. None of that amounts to anything more than a red herring, of one flavor or another, to divert attention from the basics of controlled testing. The truth is that you can perform an ABX test all by yourself without any pressure from other participants, that you can take as much time as wish (how about 16 trials over 16 weeks?), and that you can verify the transparency of the inserted control devices with a straight-wire bypass. The objections are totally bogus and hypocritical.

Here’s how you smoke out a lying, weaseling, obfuscating anti-ABX hypocrite. Ask him if he believes in any kind of A/B testing at all. He will probably say yes. Then ask him what special insights he gains by (1) not matching levels and (2) peeking at the nameplates. Watch him squirm and fume.
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According to the Audio Engineering Society, people can not tell the difference between CD & Super Audio CD in ABX double blind testing.
This topic has already been discussed. Please do a search first.
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http://en.wikipedia.org/wiki/Sacd

How many of the participants had some form of presbycusis?
Well, perhaps one day someone might be able to hear a difference.
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The vast majority of audio engineers state that even the untrained ear can hear a noticable difference between a Super Audio CD and a regular CD.

SA-CD FAQ

http://www.ps3sacd.com/sacdfaq.html
Quote:
Can I hear the difference?

While the difference between regular audio CD and the high-density layer of SA-CD can be quite easily perceived, even to untrained ears, the sound difference between SA-CD/DSD on the one hand and DVD-Audio/hi-res PCM on the other hand will be more subtle.
Those ABX tests have shown that no one was able to hear a difference.
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So just drop the ABX testing posts.
Please see the above and my signature.
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Just respect my right to trust my ears, and stop harrassing me.
Please see the above and my signature.
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If you're talking about your status on this board, skip252 make his point to me in a VERY respectful way.
You claimed that I was dense.
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There is nothing respectful in your posts to me. It show a lack of upbringing and tact on your part. You're embarassing yourself, NOT me.
I apologize. I will try to be more respectful to you in the future.

Last edited by Enigmatic; 10-22-2011 at 06:41 AM. Reason: minor
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  #26  
Old 10-23-2011, 04:01 PM
saratoga saratoga is offline
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Celestial Being:

I saw a bunch of misconceptions about SNR in those edited posts. You need to remember that SNR isn't really meaningful for lossy audio. In reality SNR is basically just another way of saying bitrate. For this reason you need to use ABX tests to determine if one mp3 file is better then another. Just comparing the SNR will give you bad (or even flat out wrong) results because theres no reason to think a file with higher SNR will sound better then one with lower SNR given how the psychoacoustical processing in modern lossy encoders work.

Since it seems like you haven't really looked much into how all these things work, I'm going to repeat my earlier advice: just use lame -v2 with the latest lame version. The encoder will worry about things like q settings and SNR for you in order to give you the highest quality. Trying to double guess the encoder without fully understanding whats going on is just going to led you astray.
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  #27  
Old 10-23-2011, 04:52 PM
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Seeing as this immature kid rage-quit with a rather rude message, even though people really tried to help him, I think it's time to show him to the door.
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  #28  
Old 10-23-2011, 05:03 PM
saratoga saratoga is offline
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Wow didn't notice he'd edited every single post he'd ever made. That's pretty . . . special to have that kind of free time to spend raging on the internet.
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