The Dumbing Down of Audio

[jdswph]

Right on Gene!

Gene sums up the issues with today’s technology.

I am reminded of promises of technology from early Sprint commercials "You can hear a pin drop". Remember that?

Today convenience has become more important than quality. People used to be upset if there was a crackle on their wired telephone but now accept mediocre quality and dropped calls with cellular technology. They also used to be impressed with the CD; you can play it without pops or clicks in full resolution. Today they're impressed when the MP3 player holds 130 albums at one quarter of the original resolution!

Not for me.

 

[gene]

Gene sums up the issues with today’s technology.

I am reminded of promises of technology from early Sprint commercials "You can hear a pin drop". Remember that?

Today convenience has become more important than quality. People used to be upset if there was a crackle on their wired telephone but now accept mediocre quality and dropped calls with cellular technology. They also used to be impressed with the CD; you can play it without pops or clicks in full resolution. Today they're impressed when the MP3 player holds 130 albums at one quarter of the original resolution!

Great points! Thanks for the feedback.

 

[MDS]

Not true. MP3 don't discriminate that way between genres. If anything, some modern 'green block' hypercompressed and limited rock and pop might pose more of a challenge for codecs , than music with a natural sonic imprint.

You are way too zealous in your defense of MP3. I did not imply or state for that matter that the codec identifies the genre. It is the characteristics of Jazz and Classical music that is often difficult to encode well. Rock or Pop that just happens to have similar characteristics will also be difficult to encode well. The probability that a hyper-compressed Rock track will clip when encoded as MP3 is 1.0 (100%).

MP3 is a general purpose codec designed to be suitable for a wide range of music. It is a jack-of-all-trades and therefore by definition cannot be perfect for everything. Mostly I agree that it works extremely well but I do have a small amount of music where it is possible to tell the difference between the MP3 and the uncompressed WAV (subtle though it may be).

 

[krabapple]

You are way too zealous in your defense of MP3. I did not imply or state for that matter that the codec identifies the genre. It is the characteristics of Jazz and Classical music that is often difficult to encode well. Rock or Pop that just happens to have similar characteristics will also be difficult to encode well. .

What characteristics are those?

 

[WmAx]

Might I suggest you have another expert take a closer look at Chris Tham's results, whihc you reference in this editorial? I'm not convinced they demonstrate what they claim to demonstrate.

Indeed. If I use the same method(arbitrarily picking a narrow part of the spectrum in a FFT spectrograph) of quoting dynamic range as Tham, then my $30 Soundblaster Live! 24 bit sound card has a 130dB dynamic range. However, the Adobe Audition calculated values are the correct ones, which Tham did not seem to like. Then we can get into the fact that Tham did not analyze the formats at all, but instead, really all she did was show properties of different mastered versions of the same album. An important issue, I believe, because the article seems to be written in a way that it is about the formats, when really it is not. The only format that was able to be analyzed, at least partially, is the LP version, simply because it's inherant noise floor was so high as to exceed that of the mix(which is never all that good most of the time anyways unless digital sound reduction filters are used).

-Chris

 

[gmichael]

IMO Ipods beat the heck out of the quality of carrying around a transistor AM/FM radio. They serve a great function to be able to bring your music with you. But when some people bring them home and use them as their source of music is when the real joy of listening is being lost. Some seem to think that they are hi-fi. Not so. But they have their place. And thank G.d for them.

 

[Steve1000]

That's been my experience too. Thanks for taking the time and trouble to add what I think is a more correct perspective.

128 kbps runs a moderate chance of sounding different from CD, but higher bitrates don't. You may be surprised to find how difficult it can be to tell a
high-variable bitrate MP3 from source. The codecs have gotten VERY good in the last few years.

 

[Steve1000]

Absolutely.

There's nothing wrong with the audio quality of the ipod. It's all in how you use it. Personally I think a much bigger danger is the hearing loss from constant listening to loud modern mastering at loud levels, over earbuds. This isn't *intrinsic* to ipod or any other device, it's just a matter of common practice.

 

[rolski]

IMO....They serve a great function to be able to bring your music with you....Some seem to think that they are hi-fi....But they have their place....And thank G.d for them.

My sentiments exactly.
I used to carry approx 15Kg of CD's around with me when I travelled, now I just have my iPod & Etymotics - and also a far larger cross-section of my music to enjoy. However, since my tender teenage years I have always listened to music-on-the-move, so portable audio is not new to me, but it sure is more convenient now !

Most of my friends have similar MP3 players, but I spend time with them explaining that this is great, but not as good as it could be. They see & hear my rig at home & are amazed, but then I take the time to explain that they don't have sell their house to get good sound - four of my male friends & one female have got into HiFi in the last 12 months as a result of this.

Good music & its reproduction are an inherent part of quality of life - everyone has memories (good & bad) triggered by hearing a certain tune - it's the way our brains are wired.
Moral of the story ? For those of us who enjoy or are obsessed by Hifi, stop bleating & complaining about the dumbing-down of Audio & get out there and do something about it !

 

[tbewick]

I'd like to have a quick bash at film soundtrack 'dumbing down'. Many modern films suffer from excessive volume [1]. I feel this stems from the fact that films are no longer necessarily played at reference level in the cinema. Film makers therefore feel the need to boost the dialogue volume in order that dialogue is audible in theatres not playing back at reference level. Indeed, the film industry is in someways more worthy of criticism because a reference level does exist for playback, which is not the case in the music industry.

'The loudness of the soundtrack is a problem we feel needs improving. Even though the Dolby LEQ programme has helped control the level of trailers and cinema advertising, many feature films are still too loud, especially movies designed for children and the family. We are often all under pressure to increase the loudness in our mixes, but the effect on the audience really must be considered. The majority of cinemas decide on the second option and lower the listening level and subsequently the dialogue suffers. We feel that Dolby has always been at the forefront and perhaps discussion should be encouraged to attempt to rectify this problem.'

- [2] Dolby interview with Eddy Joseph, Graham Daniels and Ray Merrin.

I'd also like to have a pop at the 0 dB FS Audioholics article linked to in the 'Dumbing Down' article. The article is so bad and misleading that it could belong on the Stereophile website. I did read the 0 dB FS some time ago and remember the comments about how CD's from the plant don't sound as good as the original master. This is ridiculous. Are you trying to tell me that it's possible to include a free DVD with my newspaper but a 25 year old digital format cannot be correctly manufactured? What about error correction? I also think that the point about digital clipping is irrelevant. Maybe an early CD player with only 14 bit accuracy would have trouble with hot mixes, but surely not any modern equipment!

[1] http://www.dolby.com/assets/pdf/tech_library/54_Moviestooloud.pdf
[2] http://www.homecinemachoice.com/articles/hccarticles/interviews/200111DolbySound/200111DolbySound1.php

 

[gene]

I'd also like to have a pop at the 0 dB FS Audioholics article linked to in the 'Dumbing Down' article. The article is so bad and misleading that it could belong on the Stereophile website. I did read the 0 dB FS some time ago and remember the comments about how CD's from the plant don't sound as good as the original master. This is ridiculous. Are you trying to tell me that it's possible to include a free DVD with my newspaper but a 25 year old digital format cannot be correctly manufactured? What about error correction? I also think that the point about digital clipping is irrelevant. Maybe an early CD player with only 14 bit accuracy would have trouble with hot mixes, but surely not any modern equipment!

You obviously read the title of the article, but likely not its content, the references and endorsements by many pros in the industry as to why this happens. It is deliberate!

I suggest reading the article in its entirety, examining the measurements and related links within the article before further commenting. Digital clipping is a very real and documented problem. Error correction cannot resolve this and has no bearing in this discussion.

 

[tbewick]

I'm sorry that I didn't click on the link you gave in the article, because I thought that it was referring to an article I had read previously. I did manage to find the part I was referring to here, which is from the article I did read:

'I don't think I've ever had a CD come back from a plant that sounded as good as the PMCD I sent them (really unscientific claim, sorry...but in an a/b comparison using the same d/a converter the difference is obvious to the CLIENT...Some studies, though informal, have found that higher burn speeds of the glass master at the CD production plant cause the "digital pits" that are inscribed on the CD to be less uniform. The lack of precision will cause higher timing jitter and increased errors. Typically timing jitter will cause more distortion of low amplitude signals, and more distortion of higher frequency signals.'

- http://www.audioholics.com/techtips/specsformats/currentrecordingtrendsP12.php

Is there any good evidence showing that this is important? The CRCC encoded data is read off the CD and then goes through error correction, which to all intents and purposes is perfect. If there is a large stream of uncorrectable errors, you'll hear clicks or interruptions in playback. All jitter should be rejected at this stage. Jitter should only become an issue when using a digital interface and/or when the data is sent to the DAC. Based on the discussions I've had on the forum before, in a typical system it is unlikely that jitter would produce audible results.

I have read the AES paper and related articles in the past. I did do a small, unscientific comparison on a highly compressed, digitally extracted recording normalised to 50 % (~14 bit) and 100 % levels. I couldn't hear any obvious differences. The recordings sounded bad in both instances. In my view, digital clipping is a non-issue because a highly compressed recording probably sounds bad with or without digital clipping. This goes along with the assertion, made in the articles themselves, that these tests for digital clipping serve no purpose.

On a good recording, any digital clipping would be of limited duration and therefore inaudible. I would say that the poor sound quality of highly compressed recordings is almost entirely due to the use of limiters and compressors in mastering. This is readily verifiable by extracting the audio digitally and examining the waveform. Digital extraction of the audio would not be subject to digital clipping as it is only a case of reading off the correct data from the CD.

 

[tbewick]

I had another read through all the articles again and quite frankly there is quite a lot of rubbish here. The dynamic comparison article is so bad that probably even Stereophile would not publish it.

'Note that the values for the CD recording are not as "good" as the EAC digital rip. This gives an indication of the difference between CD "real world" performance vs "theoretical" performance.'

The last sentence here is particularly ambiguous. This test is not fair because the ADC will introduce noise and distortion. In a well-designed system, ADC's have more of an affect on performance than DAC's. This is why digital interfaces were developed, so that quality would not be reduced in multiple ADC/DAC conversion stages.

'In other words, the LP recording has a lower noise floor than the CD recording for the majority of the spectrum (frequencies above 2kHz ).
LP's surface noise, which is responsible for the poor dynamic range, is mainly concentrated below 500Hz where the noise level is around -50dB. '

This noise is highly deterimental to sound quality as LP bass performance is severely limited by noise. Anyone who had listened to vinyl would tell you this.

'As you can see, the noise floor is convincingly below -90dB all the way down to 400Hz. So it would appear LPs do have a reasonable dynamic range for the majority of the audible frequency range.'

Not all of the audible range! Below 400 Hz is very important and contains a cosiderable amount of sound information.

'Many vinylphiles have long claimed that they can hear "below" the noise floor of their LPs. My observations would seem to partially support this claim: surface noise is fairly "structured" (it has a distinct "sound" as opposed to random noise) allowing our brain/ears to "filter" it away and listen to the "music" all the way down to the "real" underlying noise floor which is comparable to CD.'

Random noise is more benign than structured noise! Are you seriously trying to tell me that vinyl rumble is more desirable than white noise 90 dB below the signal level?

'LP's difference between maximum to average is around 11.56dB, compared against the CD recording at 11.11dB and even the digital rip at 11.35dB.'

What does this prove? There's a good chance than the vinyl has a lower average volume because of wear and usage. You don't even have the original master tape for comparison.

'This finding supports my own subjective impressions comparing the CD against the LP. I much prefer listening to the LP over the CD on my system. The CD sounds dull, congested, muddy, and lacking in dynamics. If I push up the volume, the sound becomes noticeably harsh and artificial. The LP on the other hand sounds more "dynamic" and "exciting." '

This could be taken right from Stereophile.

'I suspect a lot of this spectral information is harmonic distortion and there is not much useful frequency content significantly above 20kHz in the original master tape.'

The first mention of harmonic distortion. Don't LP's introduce considerably more harmonic distortion than digital formats? How about wow and flutter? What audible affect are these higher frequency components meant to have? From what I know, frequencies above 20 kHz are not audible.

Quotes from:
http://www.audioholics.com/techtips/specsformats/LPvsCDformats2.php

 

[Dan Banquer]

Well it certainly appears from the post above that Gene has once again hit the nail on the head. The articles that this web zine posts of this nature are peer reviewed by a number of sources, including well respected recording engineers, and electrical engineers, who are not part of the Audioholics staff. None of which are on the staff at Stereophile by the way.
Hyper compression is most definetly destroying music and CD correction systems are not designed to handle it. If you wish more technical papers on this subject send me an e mail address and I will send some. AES Level 109 by Lund and Sorenson is a good one to read.

I have noted no comment from anyone in this thread on the dumbing down of pop music. Am I missing something?
d.b.

 

[JoeE SP9]

<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><A href="http://www.audioholics.com/news/editorials/DumbingDownAudio.php"><IMG style="WIDTH: 125px; HEIGHT: 103px" alt=[cube] hspace=10 src="http://www.audioholics.com/news/thumbs/cube_th.jpg" align=left border=0></A>Despite our advances in science, one divine truth can always undermine us – <I style="mso-bidi-font-style: normal">marketing</I>.<SPAN style="mso-spacerun: yes">&nbsp; </SPAN>I fear we are breeding a generation of ignorance to music and fidelity playback. <SPAN style="mso-spacerun: yes">&nbsp;</SPAN>If you haven’t heard an unamplified musical performance recently, do yourself a favor and attend one.<SPAN style="mso-spacerun: yes">&nbsp; </SPAN>Your ears will thank you for it.<SPAN style="mso-spacerun: yes">&nbsp; </SPAN>If your only exposure to music is via a compressed playback system (ie. iPOD, MP3) and cubed speakers, consider one of our Recommended Systems.<SPAN style="mso-spacerun: yes">&nbsp; </SPAN></SPAN><?xml:namespace prefix = st1 /><st1ersonName><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Don</SPAN></st1ersonName><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">’t get dumbed down, do this to preserve the sanctity of your own musical intelligence. <?xml:namespace prefix = o /></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">[Read the Editorial]</SPAN></P>

For myself and I presume most of us here, you are preaching to the already converted.

 

[tbewick]

Well it certainly appears from the post above that Gene has once again hit the nail on the head. The articles that this web zine posts of this nature are peer reviewed by a number of sources, including well respected recording engineers, and electrical engineers, who are not part of the Audioholics staff. None of which are on the staff at Stereophile by the way.
Hyper compression is most definetly destroying music and CD correction systems are not designed to handle it. If you wish more technical papers on this subject send me an e mail address and I will send some. AES Level 109 by Lund and Sorenson is a good one to read.

I have noted no comment from anyone in this thread on the dumbing down of pop music. Am I missing something?
d.b.

I don't have any problem with the data presented on digital clipping, I just don't think that for these pop/hyper-compressed recordings it's important. The stuff is hyper-compressed and deliberately clipped all over the place to start off with. I don't see that digital clipping is going to make it much worse - 'garbage in, garbage out'. This is my conclusion after extracting such tracks and normalising to around 6 dB below full-scale - the tracks still sound rubbish. For well produced recordings with less compression, I can't see how digital clipping is an issue either. There may be a few peaks around full-scale, but these peaks will be of such short duration that any digital clipping would be inaudible.

In a technical sense, I know that digital clipping is something to be considered. In a Dolby white paper I read a while ago, one of the said benefits of using AC-3 dialogue normalisation is the introduction of more digital headroom. If, however, you look through the Audioholics articles, you'll see that there are a lot of Stereophile-like, unjustified, unsubstantiated, and generally misleading statements like the ones I commented on earlier in the dynamic comparison of LP, CD, DVD-A, and SACD. I wouldn't have a problem if the comparisons were made with reference to the original studio master tape, but without this, the tests don't show anything of value. In any case, I've never come across any good arguments against the fact that CD is an entirely transparent format. As for those claims against CD manufacturing plants, I don't care who made them, they're utter nonsense.

 

[Dan Banquer]

I don't have any problem with the data presented on digital clipping, I just don't think that for these pop/hyper-compressed recordings it's important. The stuff is hyper-compressed and deliberately clipped all over the place to start off with. I don't see that digital clipping is going to make it much worse - 'garbage in, garbage out'. This is my conclusion after extracting such tracks and normalising to around 6 dB below full-scale - the tracks still sound rubbish. For well produced recordings with less compression, I can't see how digital clipping is an issue either. There may be a few peaks around full-scale, but these peaks will be of such short duration that any digital clipping would be inaudible.

In a technical sense, I know that digital clipping is something to be considered. In a Dolby white paper I read a while ago, one of the said benefits of using AC-3 dialogue normalisation is the introduction of more digital headroom. If, however, you look through the Audioholics articles, you'll see that there are a lot of Stereophile-like, unjustified, unsubstantiated, and generally misleading statements like the ones I commented on earlier in the dynamic comparison of LP, CD, DVD-A, and SACD. I wouldn't have a problem if the comparisons were made with reference to the original studio master tape, but without this, the tests don't show anything of value. In any case, I've never come across any good arguments against the fact that CD is an entirely transparent format. As for those claims against CD manufacturing plants, I don't care who made them, they're utter nonsense.

Try www.digido.com for additioonal information. This is Bob Katz's web site and contains a lot of information on many of the issues of digital mastering.
d.b.

 

[nibhaz]

I have noted no comment from anyone in this thread on the dumbing down of pop music. Am I missing something?
d.b.

Well, I was under the impression that the label “pop” music and “dumbed down” were interchangeable terms and have been so for quite sometime.

 

[ScottMayo]

Is there any good evidence showing that this is important? The CRCC encoded data is read off the CD and then goes through error correction, which to all intents and purposes is perfect. If there is a large stream of uncorrectable errors, you'll hear clicks or interruptions in playback. All jitter should be rejected at this stage. Jitter should only become an issue when using a digital interface and/or when the data is sent to the DAC. Based on the discussions I've had on the forum before, in a typical system it is unlikely that jitter would produce audible results.

There's a strange misconception around, that the timing of the pits on the CD causes jitter and affects music. It doesn't. The CD format is designed around the idea that no motor is perfect, and so the bits on the disk have inevitable timing variations - both when written and read. That doesn't matter. Those bits aren't played as music. They are simply copied to a buffer ahead of time, and a *stable clock* is used to read the bits out with precise timing. Disk timing doesn't matter, as long as the bits can be copied to the buffer. Clock timing does matter, and just about any audiophile grade CD player has a decent clock. Spread the word!

On the other hand, the checksum used for redbook is not really very good. It doesn't correct all errors, or even close. A few hours with EAC has convinced me that this is a real problem - even with software designed to do rereads and extra correction work - something a regular CD player wouldn't have time to do - you can get copies that are not 100% accurate. I always advise people - bring your new disk home, and rip it first thing. Before it gets dirty and scratched.

 

[MDS]

On the other hand, the checksum used for redbook is not really very good. It doesn't correct all errors, or even close. A few hours with EAC has convinced me that this is a real problem - even with software designed to do rereads and extra correction work - something a regular CD player wouldn't have time to do - you can get copies that are not 100% accurate. I always advise people - bring your new disk home, and rip it first thing. Before it gets dirty and scratched.

Ahhh...the cult of EAC again.

How would one determine that a copy is not 100% identical? You cannot. All EAC does is re-read a few times because the laser can only get to within 1/75 of a second of the actual beginning of the track and each time you read it could be 1/75 too soon, right on, or 1/75 too late. It takes the read that occurs the most number of times as the 'correct' one. A modern CD drive will return the same data on every read.