Sound quality - 192KBPS and less

[Febs]

Originally Posted by DrBenway

So if one is to change the recording, with whatever risks that entails, one should have a good reason. Saving disk space? Not a good reason.

Perhaps it is not a good reason to you, but it is a very good reason for me and for millions of others. While I'm sure the day will come when small portable players will have essentially unlimited storage space, that day has not yet arrived. Therefore, lossy compression schemes are valuable to me and many others.

(As I've said many times, however, at home, where storage space is for all practical purposes unlimited, I use FLAC or WavPack.)

If space is not a concern for you and you choose not to use MP3 or other lossy formats, I have no quarrel with that. But I do have an issue if you or Stereophile or anyone else claims that a well-encoded MP3 is audibly different from the source without conducting a listening test to support that claim.

[Hi-Fi Low-Life]

Originally Posted by Febs

But I do have an issue if you or Stereophile or anyone else claims that a well-encoded MP3 is audibly different from the source without conducting a listening test to support that claim.

I’ve already stated that the signal degradation that Stereophile was able to illustrate was probably not audible to most listeners, but what I still don’t get is why someone else’s listening tests would be important to you. If Stereophile had conducted a listening test that indicated MP3s were audibly inferior, would you stop listening to MP3s? I wouldn’t because the only listening tests that are valid to me are my own!

[DrBenway]

Originally Posted by Febs

Perhaps it is not a good reason to you, but it is a very good reason for me and for millions of others. While I'm sure the day will come when small portable players will have essentially unlimited storage space, that day has not yet arrived. Therefore, lossy compression schemes are valuable to me and many others.

(As I've said many times, however, at home, where storage space is for all practical purposes unlimited, I use FLAC or WavPack.)

If space is not a concern for you and you choose not to use MP3 or other lossy formats, I have no quarrel with that. But I do have an issue if you or Stereophile or anyone else claims that a well-encoded MP3 is audibly different from the source without conducting a listening test to support that claim.

You have a good point, assuming that it is important to carry around a huge amount of music. Without casting aspersions on you, or anyone else who has that as a priority, I have to confess that this is not a priority for me. The most capacious player I have ever owned is my current one, a Sony RH1.

The 1GB per disk that it offers is more than enough for me. I'm rarely away from my PC for more than a day, so I can refresh my portable with new music on a daily basis. I guess it's cool to have your entire collection at your fingertops (in a perfect world, I'd go for that in a second!). But I am completely cool with making choices as to what goes (or doesn't go) on my portable for the next day or so. I see no reason to opt for degraded files in order to have more music available to me.

There's an old joke:

Q: How was that restaurant you went to last night?

A: Well, the food was not so good, but at least the portions were big.

[monolith]

Originally Posted by Hi-Fi Low-Life

I’ve already stated that the signal degradation that Stereophile was able to illustrate was probably not audible to most listeners, but what I still don’t get is why someone else’s listening tests would be important to you. If Stereophile had conducted a listening test that indicated MP3s were audibly inferior, would you stop listening to MP3s? I wouldn’t because the only listening tests that are valid to me are my own!

It's not a matter of how it affects him. He's already stated that under rigorous conditions he can't distinguish original from mid-bitrate mp3. This only has to do with the authors making baseless claims and passing them off as credible.

[Hi-Fi Low-Life]

Originally Posted by monolith

This only has to do with the authors making baseless claims and passing them off as credible.

If one follows the various links in the article, Stereophile does a pretty good job of justifying their positions. One case in point is the link to their comparative listening test: Stereophile: Watching the Detectives

I don’t agree with Stereophile’s ultimate conclusions regarding MP3 sound quality, but I’m not going to dismiss their technical and listening tests just because they don‘t validate my own experience with MP3.

[b0dhi]

Originally Posted by Febs

No-one disputes that MP3 encoding changes the source file, and has effects such as high-frequency roll-off. The significant question is whether those changes are audible.

Originally Posted by Febs

Similarly, there was a poll a while back asking "Can you hear a difference between -V 0 and the original?" Out of approximately 100 respondents, only about 25% claimed that they could hear a difference, and out of that 25, only 2 actually substantiated their claim with ABX results as the rules of the poll required. Hydrogen Audio listening tests have show that new versions of LAME reach transparency somewhere around -V5.

In the one quote you suggest that it's undetermined whether the effect of MP3 encoding is audible. In the second quote you cite evidence that the differences are audible. I can also send you my results for the Public ABX test (at p<0.001), showing that LAME -v2 is distinguishable from lossless. That doesn't mean everyone can hear the difference, but between the various substantiated ABX results published here and elsewhere, I think it's fair to assume that high bitrate lossy/lossless are distinguishable. Given that, and given that the article is directed at those that can hear the difference, it isn't unreasonable for the author to come to the conclusion they did: -

There seems little point in spending large sums of money on superbly specified audio equipment if you are going to play sonically compromised, lossy-compressed music on it.

Also, the fact that they've used JPEG for the images speaks more to the webmaster than to the article's author. I'd have used GIF or PNG, but only because it would've looked nicer, not because the compression they've used affects the interpretation of the data. For the type of graph shown, JPEG, at the quality level chosen, is good enough. If the data were represented using colour/intensity gradients, that would be a different story because compression artifacts would alter the interpretation of the data.

[Logistics]

Contrary to your post, there is no way that I could prove that you cannot hear a difference, and I would never attempt to do so in any event. It is entirely possible--though unlikely--that you in fact in the very small minority of people who can distinguish a 320kbps MP3 from the original. However, given the fact that so many make that claim yet so few can actually do it, I will remain skeptical of your claim unless and until you support it with ABX test results.

So if I did an ABX test and I could in fact hear a difference, this would affect your life how? Really, posts like that are not productive nor constructive. If you made exactly the same changes to your rig as I do and you can't hear a difference, but I can then what would it matter? Why do you care?

Originally Posted by Hi-Fi Low-Life

what I still don’t get is why someone else’s listening tests would be important to you.

Exactly! It's pretty obvious that the only purpose his comments are serving is to irritate people. It's like a child whining that someone else said they can get a higher score on Pole Position and then calling them out on it; wanting them to prove it. WHO CARES?!

[bigshot]

Originally Posted by Hi-Fi Low-Life

If Stereophile had conducted a listening test that indicated MP3s were audibly inferior, would you stop listening to MP3s?

I would try to recreate their results myself. A controlled test should be repeatable and verifiable. If my results were radically different than the results of most controlled testing, I wouldn't dismiss the possibility that my testing method isn't controlled enough. It would just make me want to pin it down more accurately.

See ya
Steve

[bigshot]

Originally Posted by DrBenway

You have a good point, assuming that it is important to carry around a huge amount of music.

This is the main benefit of the iPod over other sources. I can't think of a better reason. Music is all that matters ultimately. The more music the better.

See ya
Steve

[Febs]

Originally Posted by Hi-Fi Low-Life

If one follows the various links in the article, Stereophile does a pretty good job of justifying their positions. One case in point is the link to their comparative listening test: Stereophile: Watching the Detectives

I don’t agree with Stereophile’s ultimate conclusions regarding MP3 sound quality, but I’m not going to dismiss their technical and listening tests just because they don‘t validate my own experience with MP3.

Unfortunately, that "listening test" is seriously flawed. First, it is single-blind, not double-blind. Second, there are two sample rate conversions that took place that may have impacted the sound of the files. Third, they don't identify the encoder that was used to create the MP3s.

Originally Posted by b0dhi

In the one quote you suggest that it's undetermined whether the effect of MP3 encoding is audible. In the second quote you cite evidence that the differences are audible. I can also send you my results for the Public ABX test (at p<0.001), showing that LAME -v2 is distinguishable from lossless. That doesn't mean everyone can hear the difference, but between the various substantiated ABX results published here and elsewhere, I think it's fair to assume that high bitrate lossy/lossless are distinguishable. Given that, and given that the article is directed at those that can hear the difference, it isn't unreasonable for the author to come to the conclusion they did:

The conclusion that I really take issue with is not the one that you quote, but this one: "Although they are universally described in the mainstream press as being of "CD quality," MP3s and their lossy-compressed ilk do not offer sufficient audio quality for serious music listening."

I simply don't see that the analysis that they did is sufficient to justify their conclusion, especially considering that they apparently have not attempted to do any serious evaluation (through listening tests or otherwise) with more modern encoders.

But thank you for pointing out to me that you passed the Public ABX test. I did not re-read that thread before making my post and either you did not post your results there or I simply missed the fact that you had. It is not my intention to spread misinformation and if I did, I sincerely apologize.

Originally Posted by Logistics

So if I did an ABX test and I could in fact hear a difference, this would affect your life how? Really, posts like that are not productive nor constructive. If you made exactly the same changes to your rig as I do and you can't hear a difference, but I can then what would it matter? Why do you care?

It really doesn't matter much to me personally, because I have done my own testing and reached my own conclusions on what works for me. I care because threads like these can cause people--particularly those new to these concepts--to think that they should be able to hear differences that the vast majority of the population cannot hear. I think that it is useful in these discussions to keep some perspective on how good (or bad) lossy codecs really are. There is a great deal of hyperbole and unsupported claims (e.g., "all 128kbps suck!" or "if you can't hear a difference, it's because your gear isn't good enough") made by people based on faulty or anecdotal evidence, or worse, hearsay. The truth is that lossy codecs have become very, very good at what they do.

I've expressed this concept much more articulately in the past and if I have a chance later, I'll try to do so here as well, but for now, I have to get back to work.