DT12 CD vs HDTracks - A visual representation

[rumborak]

The graph changed.  Doesn't the red (non-HD) actually have a wider dynamic range spread?

Sorry, yeah, the scaling of the two graphs was difficult because the HDTracks have no gaps, whereas the non-HD does. That rescaled the two funny, which I now fixed.

[BlobVanDam]

Is that graph taking into account the different bit rate of the HD version? It looks too different.

[rumborak]

I dowbsampled both to the same bit rate and bit depth.
And, doing the A/B comparison, I actually don't think it's off. I had to immediately reach for the volume knob when I put on the non-HD version.

[BlobVanDam]

There is an obvious difference in the volume of the two, I guess it's just not a graph comparison I'm used to seeing.

[425]

I wish they would just release the dynamic versions.  Most hardware players have some sort of loudness button, Replay Gain, leveling feature.  The problem is you can take a dynamic version and compress/squeeze it to have the loudness factor for noisy listening environments.  But you can't go the other direction.

I think the issue is that most listeners have no idea how to do that. For right or wrong (it's wrong, but...), I suppose the people who are doing this are assuming that it's better to have Joe Schmoe be able to hear the music through his Apple earbuds while riding on the subway than to appease what is probably a minority group of people who are conscious of and bothered by the loudness. Now, the thing is, Apple does provide on the iPhone what is as near as I can tell something to boost loudness. So, I assume, does Android. But in order to get to that, Joe Schmoe has to know what he's doing. It's located deep in the music player settings under a long list of various things titled simply "EQ."



I would have no idea what I was looking for if I didn't know what loudness was. I would have no idea even to look for something if I didn't know what loudness was. So that's the problem, I suppose, in the eyes of some the people compressing things.

If Apple and other smartphone software designers were to place some sort of Loudness toggle right in the music player and made it clear to the general public that you can use that when you're on public transportation and there's a lot of ambient noise, but that it reduces audio quality, then the excuse would go away. But I highly doubt that the loudness war is on the radar of most software designers. Plus, the situation I am describing is a chicken/egg situation: there'd be little point in making an easily accessible loudness toggle unless a significant amount of popular music started being released in much more dynamic versions, and it would be unlikely that that would be done without an easy way for the common user to change the loudness.

[seasonsinthesky]

Apple devices use a ReplayGain-esque thing called Sound Check to level out loudness so it's the same across playback for your whole library. unfortunately, it's track-based, so it'll throw off transitions on continuous albums... and i've noticed it sometimes gets the volume wrong (i don't think it accounts for the Fletcher-Munson curve, so it doesn't focus on the frequencies we hear best, just overall volume).

there's also a feature in the Info dialog box on iTunes that lets you adjust the volume of every song during playback.

[rumborak]

The graph changed.  Doesn't the red (non-HD) actually have a wider dynamic range spread?

You know, I've only been listening to the HDTracks now for the first time, and yeah, to be perfectly honest, I think they do not all much more than pulling down the volume overall. The audio is still over-crowded and wall-of-soundy, just at a different volume level. That volume level is a better operating point, sure, but as you say, the dynamic range itself didn't increase at all. That new headroom they got, is totally unused.

EDIT: You know, I just compared direct waveforms between HD and non-HD. I am pretty sure they did nothing but pull down the volume, and then upsample the signal.

[425]

Apple devices use a ReplayGain-esque thing called Sound Check to level out loudness so it's the same across playback for your whole library. unfortunately, it's track-based, so it'll throw off transitions on continuous albums... and i've noticed it sometimes gets the volume wrong (i don't think it accounts for the Fletcher-Munson curve, so it doesn't focus on the frequencies we hear best, just overall volume).

there's also a feature in the Info dialog box on iTunes that lets you adjust the volume of every song during playback.

Yeah, but Sound Check is optional and off by default (thankfully, for people like me). Anyone who doesn't know or care much about sound quality isn't going to know or care what Sound Check is.

What I'm saying is that much of the justification for compressing albums—or, at least, the only use case where compressed music sounds better than uncompressed music—is when you're listening in a loud place (like public transit) without noise-reducing headphones or earphones. And many of the people who are doing that are people who don't know what things like compression or loudness—in the context of mastering—mean. That's a big part of the idea behind that. If you're in a subway during rush hour listening to music on your little white plastic earbuds, DT12 CD version is going to sound better than DT12 HDTracks because it's louder. And that's the only time it'll sound better. I'm saying it would help immensely if it was easy and intuitive for Joe Schmoe who doesn't know anything about engineering to switch on and off some form of audio compression. If there was an easy-to-access toggle for something like "Loud Room Mode" (obviously it could have a better name but something that is that obvious to the layperson as to what it means) that would turn on a form of audio compression, that would take away the last remaining advantage of just making everything compressed always.

[rumborak]

It wouldn't need to be a toggle. The smartphone could detect the level of ambient noise, and adjust the compression on the fly.

[425]

That would be pretty cool. However, I would want the option for it to not do that, somewhere in the settings. Maybe what you're talking about could be a system that is on by default, since the average user would want it on, but could be turned off somewhere in the settings.

[rumborak]

(above CD, below HD Tracks)

Ok ... this is a kinda sad post, because it shows that the HDTracks are actually a sham. Yes, they no longer clip like the CD version, but there is no "remastering". They are the same signal. (Compare the peaks and troughs, they correspond 1:1). All they did was to pull the volume down, and because of that it clips less.

[seasonsinthesky]

... that's not a "sham." it would be if it was the same clipped master with the volume reduced, but it's clearly not – the limiter is only compressing, say, 2-3 dB instead of 8 or 9 like the CD master. you can't change that without using the final mix and mastering it differently. if one did, say by applying some EQ changes to the CD master, the clipped peaks would get stretched diagonally, but would still clearly be lopped off.

also, the frequency analysis of the HDTracks version shows it's legitimately a higher sample rate.

not defending the lifeless mix or lack of dynamics, though.

[rumborak]

I was under the impression the idea about DT12's HDTracks is that they went back to the original and remastered it. I mean, no offense, this will have taken the guy 5 minutes to do. He brought up the studio project, pulled down the master volume by a few dB, exported it to WAV, and that was it.

[Implode]

I thought that DT's HD Tracks were merely unmastered, not remastered.

[rumborak]

I think I would call unmastered "remastered"

The point is, other than a volume reduction, which moved it out of the clipping range, HDTracks did nothing to the signal. No offense, but that's not $20 worth.

Should the CD have been like HDTracks in terms of volume? Absolutely, because the clipping on the CD is not good. But, both versions are still brickwalled. I was hoping the HDTracks was better in that regard, but as mentioned, it's nothing but the CD version with slightly lower volume.

[BlobVanDam]

It appears you're right. The HDTracks version still sounds very compressed, but it sounded less compressed to me, with more clarity in the drums/cymbals, and more separation between instruments. I can't believe that was all pure clipping. It looks like the CD version is literally double the volume, with everything hard clipped off above the maximum.

[Calvin6s]

There is a chance the compression was introduced during the initial recording stages.  You can't really fix that.  Well, they might be able to, but it would probably be the equivalent to putting color on black and white movies.

[BlobVanDam]

You'd have to seriously mess up recording an entire album like that, and it would mix differently to doing it after the fact. Given that this is the CD release, it's no doubt just the regular mastering compression. No brainer.

[farsight]

They probably mixed the song into a compressor, and overdid the compression. In that case, remastering would not fix that. There are ways that remastering can make the song more dynamic, but not return it to what it sounded like prior to mix compression.

[ariich]

I'm not sure how you've reached that conclusion, Rumby. If it's because the volume gets louder and quieter in all the same places, then that's surely because it's still all the same notes and the mix wasn't changed.

[BlobVanDam]

I'm not sure how you've reached that conclusion, Rumby. If it's because the volume gets louder and quieter in all the same places, then that's surely because it's still all the same notes and the mix wasn't changed.

I did a comparison myself, and overlaid the two waveforms, scaling the CD version to match the HDTracks version, and they're exactly the same.
If they were using different masters, yes they'd still follow the exact same pattern of loud/soft, but the waveforms wouldn't align due to compression changing the shape of the waveform, because compression is a non-linear amplification.

[farsight]

I haven't listened to the HDTracks version, but it's probable that both mastering engineers in the CD and HDTracks version found the mix to be too compressed already so they opted to not compress the master. So the two versions would look more or less the same when you look at the waveform

Or the Hdtracks version is the the same version as the cd, but just before the limiter. In that case, it's not the exactly the same as just pulling the volume down, but calling it "remastered", would be a stretch, I agree.

[rumborak]

I'm not sure how you've reached that conclusion, Rumby. If it's because the volume gets louder and quieter in all the same places, then that's surely because it's still all the same notes and the mix wasn't changed.

I did a comparison myself, and overlaid the two waveforms, scaling the CD version to match the HDTracks version, and they're exactly the same.
If they were using different masters, yes they'd still follow the exact same pattern of loud/soft, but the waveforms wouldn't align due to compression changing the shape of the waveform, because compression is a non-linear amplification.

Yeah, that's what I'm basing my conclusion on as well. A differently mastered version would (obviously) have at least slightly different waveforms. When you have identical waveforms (save the scale factor), you just have the same signal.

[erwinrafael]

HDTracks never did claim that it used a different master, right? Who made the claim tjat it is a remaster? Not them. Calling them a sham is inaccurate because all they really claim is that they are the best sounding digital music download. From the site:

"HDtracks offers music lovers the highest-quality downloads available anywhere on the web. Many digital music stores only offer heavily compressed MP3 files. When you purchase an HDtracks file, it is the same quality as a store-purchased CD. HDtracks downloads will play with no DRM on any device. In addition, HDtracks is the only site to offer full cover art and liner notes in pdf format."

[Bolsters]

I thought we already knew that it was simply not mastered, and not a remaster? I am sure I remember that being discussed all the way back in 2013 or whenever HDTracks put the album up for download.

HDTracks has only ever promised "high resolution files" as far as I recall. Sometimes they're remastered, sometimes they're not mastered at all, and most of the time they're the same master as the CD. In any case, DT12 HDTracks still sounds better than the CD even if it isn't a remaster.

[rumborak]

I think a lot of people in this forum, at least at this point, were under the impression that the HDTracks version of DT12 were *substantially* different from the CD version. I don't think people were aware that all they got is a slightly less clipping version of the same thing.

HDTracks is of course intentionally vague on the matter. For some select albums in the past they've actually done a great job (e.g. going back to the original tapes etc), and now they're riding those laurels by giving the (implicit) impression that other albums will have gotten the same thorough treatment.

[BlobVanDam]

I thought we already knew that it was simply not mastered, and not a remaster? I am sure I remember that being discussed all the way back in 2013 or whenever HDTracks put the album up for download.

By the better sound quality, we theorized/assumed it was not mastered, but now it appears it is still mastered, at least the compression stage, but not limited.

[erwinrafael]

I think a lot of people in this forum, at least at this point, were under the impression that the HDTracks version of DT12 were *substantially* different from the CD version. I don't think people were aware that all they got is a slightly less clipping version of the same thing.

HDTracks is of course intentionally vague on the matter. For some select albums in the past they've actually done a great job (e.g. going back to the original tapes etc), and now they're riding those laurels by giving the (implicit) impression that other albums will have gotten the same thorough treatment.

I don't know how HDTracks was intentionally vague on the matter when all they claimed is studio quality sound. Even John Petrucci, whose post was often cited here, never made a claim that it is mastered differently from the CD:

"This is what it sounded like as it was playing back in the mix studio. I think all music should be offered in HD!"

No claim of a different mastering that was done. Still, they gave us a different master anyway. I don't think anybody with a clear hearing would say that the HD Tracks version does not have clearer cymbals and more separation between the instruments than the CD version. You can hear it.

[rumborak]

No offense erwin, but I don't get the impression you know what a master is. This is the *same* master, as both Blob and I independently established. The only difference is a decrease in volume, which reduced clipping. That reduced clipping is likely the cause for the improved cymbal sound.
Regarding the "improved separation between instruments", if you could explain to me how the same audio signal (disregarding the clipping) can sound differently? The difference between the two is the same difference as standing 5 feet or 10 feet away from your speakers. Do you hear more separation when you step away from your speakers?

Frankly, I think a lot of the alleged improvements are really placebo.

[ReaPsTA]

Like Blob said, the difference is probably that they took off the hard limiting for the HDTracks release, which would explain a lot of the improvement in sound quality that's still there.

[erwinrafael]

No offense erwin, but I don't get the impression you know what a master is. This is the *same* master, as both Blob and I independently established. The only difference is a decrease in volume, which reduced clipping. That reduced clipping is likely the cause for the improved cymbal sound.
Regarding the "improved separation between instruments", if you could explain to me how the same audio signal (disregarding the clipping) can sound differently? The difference between the two is the same difference as standing 5 feet or 10 feet away from your speakers. Do you hear more separation when you step away from your speakers?

Frankly, I think a lot of the alleged improvements are really placebo.

I may be misusing some of the terms but I know what a master is. What I meant is that they used a different, less loud version for the HD Tracks instead of the loud CD version, even if HDTracks really only promises a CD quality version.

For the placebo effect, it is possible, but I trust what I am hearing when I play back to back the HD Tracks version (at a volume level of 50) and the CD version (at a volume level of 34). And when I say I hear more separation, I actually meant that I hear more cymbals and keyboards. So I maybe misusing the term separation again.

How about you rumbo? The graphs notwithstanding, don't you hear any difference?

[425]

I'll say that this finding is a bit disappointing, but it doesn't change the fact that the HDTracks sounds much better to me due to the lack of clipping. For me, I think it was worth the $20 for that.

I kind of had my suspicions in the back of my head, actually, relating to the other albums' HDTracks. BCSL and ADTOE don't sound that much different, just quieter, while SC is a marked improvement like DT12 that could probably be explained by they pulled the volume down thus reducing clipping. I'd confirm this, since I have all four, but I lack the necessary expertise. I'd imagine that it's the case though. I would still recommend the SC and DT12 HDTracks to anyone who gets fatigued by the CD versions, but would say that BCSL and ADTOE are probably not worth it.

[rumborak]

It's also really not all that surprising. Remastering an album from the original mix is quite the undertaking, and would only ever be possible for a few select bands/albums. Whereas, just grabbing the final master and doing a bit of volume lowering, that's something easily done.

[ariich]

Whereas, just grabbing the final master and doing a bit of volume lowering, that's something easily done.

Well, no they wouldn't do it that way, because you'd still have the clipping presumably. It strikes me that more likely is that (as many have suggested right from the start) some level of mastering was done as part of the mix, with compression applied to individual tracks. The overall mastering would therefore be simply a case of pushing the volume up. Taking that away still makes a big difference to the sound.

[rumborak]

To get a bit more technical, I distinguish between mastering and exporting here.

Mastering, in my book, is the (somewhat) artistic process of applying EQs and compressors/expanders in order to level out the frequency spectrum.
Exporting is the final step where you convert the software's internal representation of the audio (usually floating point these days).

In my interpretation this happened:
1) DT records and mixes the album
2) The mix gets sent to mastering guy, who masters it
3) The (floating-point) master gets exported down to 44.1kHz, 16-bit for CD production

Now, the hard clipping got introduced in step 3, the exporting. Floating-point audio has no volume limitations, but when converting it to 16-bit audio, it had to clip certain samples because their values were too high.

HDTracks took the *same* master from after step 2), the one in floating-point. Then, it lowered the value of the master a bit, and instead of converting to 44kHz, 16-bit, converted down to 96kHz/24-bit. The volume decrease meant that fewer samples clipped, but otherwise it is exactly the same source master.