Is there anything to this hi-rez stuff?

[TMoney]

As someone who thinks standard 16/44 redbook sounds fantastic, I'm pretty skeptical about this whole hi-rez 24-bit movement. I did some blind testing with a buddy and I thought our results were worth posting. I'd love to hear what people think.

TL:DR Folks: Just read the BOLD stuff.

So my buddy and I conducted a few blind tests to see if we could hear a difference between 24 and 16 bit versions of the same tracks. We used two albums, the 24/96 version of Alison Krauss & Union Stations Paper Airplane from HDTracks and a 24/48 rip (using dbPoweramp) of Tool's Lateralus HDCD.

Obviously using the same tracks but with different mastering jobs from different versions of the album can make quite a big difference in the overall sound. To combat this issue, we created our 16-bit tracks directly off down-sampled versions of the hi-rez tracks. I used iTunes to down-convert copies the 24/96 and 24/48 tracks into 16/44 versions.

Our test gear was:

DAC: Antelope Audio Zodiac (the basic version)

AMP: KGSSHV

PHONES: SR-009

For our tests we first listened to the hi-rez and low-rez versions of the tracks sighted so we could see if we could hear a difference when we weren't blind. Once we had listened to both the hi-rez and low-res version of the track enough to familiarize ourselves we did a number of blind test trials where either the hi-rez or low-rez version was randomly played. The listener had to identify which of the hi or low rez track they were listening to. We didn't give the listener any feedback about right or wrong answers until after the last trial was complete. A number of trials on were performed on each track before moving to the next track.

Our Results:

Even though the hi-rez and low-rez versions of the Tool tracks sounded very close, we were able to consistently identify which track was hi-rez and which track was low-rez well above the level that would occur by random guessing.

It follows that there probably is "something" lost in down-coverting tracks from 24/48 into 16/44, even if that "something" was pretty damn subtle to our ears. The fact that we consistently identified the hi and low rez tracks indicates that we definitely heard a difference between the two.

When it came to the Alison Krauss album, we were not able to consistently identify the hi-rez and low-rez version above the level that we'd get right simply by chance guessing. I really have no what this means, but I'd guess that not all 24-bit tracks are created equal. Either that, or maybe the differences between 16-bit and 24-bit is only apparent on certain albums? Honestly, without more testing I don't feel confident in making any conclusions about this. Next time we'll test more albums.

Anyways, I'd love to hear other's experiences/opinions on this 24-bit hi-rez stuff. Does this sound similar to your experiences?

Edited April 19, 2012 by TMoney

[deepak]

Just wondering why you ripped Lateralus at 24/48? It's still 16/44 even if it's an HDCD. Lateralus is not a disc that utilizes the "peak extension".

[obzilla]

Yeah I am unaware of any extended rez on Lateralus. Without enabling an upsampling DSP effect, everything comes out at 16/44.

I can easily spot the difference between Nirvana's Nevermind redbook rip, and the HDtracks 24/96 version, but they are different mixes.

[jp11801]

Nirvana was a remaster not a remix, very different things

THe Doors debut that was released high res was a remix

[obzilla]

Nirvana was a remaster not a remix, very different things

THe Doors debut that was released high res was a remix

That's right, thanks. But the point is I can identify them because they aren't really the same source, not necessarily because one has higher bit depth than the other.

I have the Doors DVDA box set, do you know how that varies from the current redbooks? It would make for a decent comparison.

On the Metallica DVDA all I can hear is how they fucked up nearly everything about that album that Metallica didn't fuck up when they recorded it, so after hearing it twice I have stuck with redbook.

[Leonardo Drummond]

An acquaintance of mine recently wrote a really interesting article stating that's objectively impossible to distinguish bewteen redbook and high resolution formats. I have no grounds to judge his work so I'll just say it's an interesting read.

He does say that frequently what happens is that, as in the Nevermind case, different mixes are released, so telling them apart is pretty easy. Still, interested to know you guys' opinions on this.

[grawk]

My take on it has always been that the primary advantage to high rez audio is you get a better master in most cases.

There are real advantages to 24 bit when it comes to doing the original recording, and to even higher bit depth during mixing/mastering, but any benefit at the listening step is psychological, from what I can tell.

[skullguise]

Agree w/Dan. Many times you hear of the hi-rez format being specially made from some better master than other sources. Since it's a niche market they sell to, it becomes a marketing/selling point, as well as something that gives potentially better sound.....

Edited April 19, 2012 by skullguise

[TMoney]

Just wondering why you ripped Lateralus at 24/48? It's still 16/44 even if it's an HDCD. Lateralus is not a disc that utilizes the "peak extension".

It was a friend's rip so I'm not totally sure. I'll have to check on that. Next time we will have to buy a few more albums on HDTracks to compare.

An acquaintance of mine recently wrote a really interesting article stating that's objectively impossible to distinguish bewteen redbook and high resolution formats. I have no grounds to judge his work so I'll just say it's an interesting read.

He does say that frequently what happens is that, as in the Nevermind case, different mixes are released, so telling them apart is pretty easy. Still, interested to know you guys' opinions on this.

You can get around this problem by using the computer to down-convert the 24-bit track into a 16-bit version. That should take the "different mastering jobs" problem out of the equation. Thats what we tried doing for this test.

My take on it has always been that the primary advantage to high rez audio is you get a better master in most cases.

There are real advantages to 24 bit when it comes to doing the original recording, and to even higher bit depth during mixing/mastering, but any benefit at the listening step is psychological, from what I can tell.

Agreed with the better hi-rez files usually having a better mastering job. That being said, a few of the SACDs I own have much less dynamic range in their mastering jobs than the original CD pressings. For some reason many of the best sounding CDs I have are older pressings from the mid/late 80s. Maybe its because mastering engineers didn't screw around as much with the mastering back in the old days?

Based on how close our "hi" and "low" rez tracks sounded during our test I'm incline to agree with you that the differences are mostly psychological as well.

Edited April 19, 2012 by TMoney

[Spychedelic Whale]

Tmoney you may want try this for free:

http://www.soundkeep....com/format.htm

One thing that comes up repeatedly in discussions with other music lovers and audiophiles regarding CD vs. high resolution digital formats, is the fact that most folks have no means of making a valid comparison. Often, the high resolution version of a record is mastered at a different session, sometimes by a different engineer. At many so-called "format shootouts", one hears level differences, EQ differences, etc., making a true comparison of the formats impossible. Astute listeners realize these are comparisons of different masterings and not of the formats themselves.

In an effort to provide some help, Soundkeeper Recordings is providing these samples from the same album, same mastering session, etc. A number of folks we know, who use upsampling devices to play back their CDs, have found these useful in illuminating the pluses as well as minuses of their upconversion, as they can now compare the results with a true high res version.

When comparing the files, be sure your system is not performing any sort of resampling and/or dithering to either one. Some will by default, either upsample the 16/44 or downsample and dither the high resolution version.

The numbered links below will each take you to a download page.

Downloads are zipped .wav files.

http://www.2l.no/hires/index.html

We invite you to join us in this evaluation of future consumer delivery formats. FLAC is a lossless encoding of WAV-files derived directly from our production original used for the SACD and Pure Audio Blu-ray. All resolutions and encodings are derived from the same original DXD source files. Please send us an e-mail and share your experience on your practical experience with these file formats. Enjoy the music!

Edited April 19, 2012 by Spychedelic Whale

[TMoney]

Very cool. I'll check it out. Thanks for the link.

[ujamerstand]

Mind you, the down-sampling algorithms and options that you use might affect the result. How are the files encoded? What tools are you using to do the down-sampling? What are you using to perform the blind tests?

[arnaud]

I suspect not all downsampling tools sound the same because of the anti aliasing filter used.

In my experience, it has been difficult to objectively qualify the benefits of high res. recordings in the sense that it typically sounds better but it's subtle enough I can't really put the finger on what is lost when decimating / downsampling (using iTunes).

On the other hand, the jump in quality from CD to HDTracks version in case of a remaster is typically quiet noticeable.

Lastly, in some instances though it feels more like a different presentation than improved one and I suspect this may the result of a remix rather than remaster?

I use this website to correlate what I hear with the recording dynamic range and it's typically meshing rather well: http://www.dr.loudness-war.info/

[deepak]

The only fair way to compare different resolutions is if they are all the same mastering. Comparing a remastered CD to an HDTracks version isn't really the same even if they aren't remixed. As even shifting levels a couple of dB here and there when (re)mastering will make something sound different.

[Spychedelic Whale]

This should help to compare the different resamplers, sox is regarded as one of the best I think. http://src.infinitewave.ca/

[ujamerstand]

also, foobar2000's abx plugin is your friend.

[grawk]

I think the foobar abx methodology is seriously flawed. Quickly shifting back and forth like that doesn't provide much of an opportunity to catch subtle differences.

[Spychedelic Whale]

I think the foobar abx methodology is seriously flawed. Quickly shifting back and forth like that doesn't provide much of an opportunity to catch subtle differences.

I believe you tried an older version. It has 2 boxes that correspond to other 2 boxes(files). You can play the 4 boxes then guess which is which.

Edited April 20, 2012 by Spychedelic Whale

[ujamerstand]

Hrm. Is that how it operates? Just mentioned it because I thought that it'd be easier and more accurate as a testing tool, since it takes the switching off your hands. I'm all ears for a better alternative.

[Tyll Hertsens]

In general, I think the whole hi-rez thing is a red herring. Much more important is quality mastering and getting rid of the fucking loudness wars shit. At this point musicians and semi-pro recordists are so bombarded with shit recordings that they have no idea what really good sound sounds like. The art of recording, mixing, and mastering needs some fucking heros to follow. I'm fucking fed up with semi-talented people being enamored with the idea that putting artificial vinyl surface noise in the background of their mix and totally cheapening their semi-interesting music.

Producers need to pull their head out of their ass and artfully guide recording engineers before 24/96 makes any meaningful difference.

Posted while happily exploring 320kBs tracks on MOG.

[Spychedelic Whale]

[Currawong]

A late friend in California who had a very decent hi-fi system swore that the high-res versions of tracks sounded better with his Berkeley Alpha. I remember our discussions distinctly, as technically as far as the files are concerned, there should be no difference beyond a lower noise floor.

However, I've seen RMAA measurements done at 16/44.1 and 24/96 in one DAC and the latter showed, as per the logic, a lower noise floor. I have no idea how the oversampling chips work in DACs, but speculate that feeding a higher-res file to some might have some benefit in reducing the amount of oversampling done in the DAC, if there is any benefit to doing so. I know that computer-based up-sampling can be done with advanced software from iZotope or other companies which might be better than the over-sampling done in the chips.

However, as I feel my iPad sounds better as a transport in my system than my MacBook Pro using any of the various audiophile players, it's all rather moot. I think it's more a case of people getting their priorities wrong. I buy HDTracks remasters primarily for the (hopefully) higher quality processing of the original music, not specifically because they are high-res.

[purrin]

I hear a more liquid smoother presentation with 24/88 or 24/96 compared to 16/44. Could be the DAC or how the post-filter is applied differently though.

[grawk]

Or you could be hearing what you're expecting to hear, on a conscious or subconscious level.

[mikeymad]

I trust my subconscious hearing implicitly...