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Criteria to eval SQ of high res masters


mitchco

As an ex recording/mixing engineer/producer, http://www.thepikes.com/bio here are a few thoughts with respect to evaluating high resolution masters for sound quality.

 

Unfortunately, for most recordings, especially multi-track, there are many, many steps/paths from the mic to the final master we listen to. Most folks I think would be surprised to see the workflow. But that is another post.

 

The criteria I use to eval music sound quality is:

 

1) Musical performance 1st. Ultimately, if the performance is not the artists best, then the rest really does not matter.

 

2) Who recorded/engineered/produced the tracks. If you follow closely in the music genre you are most familiar with, (for me it is rock/pop), you start seeing a trend as to who has the touch and who doesn’t.

 

3) Who mastered the mix(es). Again, you will see a trend if you spend the time and effort. However, this is the most variable part of the equation as there are many, many pressing and re-masters being released. The biggest problem here is finding out which pressing/master was the source of the re-mastering. Sometimes re-mastering means a re-mix from the original multi-track sources, sometimes not. Sometimes the master is a tape generation copy as the studio/artisit does not want to touch the original (or the original has gone missing or...) Sometimes, it takes quite a bit of research to find out all the relevant info.

 

4) Finally, if the material has been re-mastered for “hi res”, then it becomes even more critical to find out where the source master came from, what processing, if any, was done to it. And that the new re-master has not become a victim of the loudness war.

 

The Loudeness War in Under 2 Minutes:

 

[video=youtube_share;3Gmex_4hreQ]

 

No question, if you are serious about the SQ of your music, then it does take effort to figure this out.

 

Some places to look:

 

Right here of course at CA!

 

Steve Hoffmans forums: http://www.stevehoffman.tv/forums/forumdisplay.php?f=2 is a primary source to look as the folks there go to great lengths and detail about performances and best pressings/masters (down to catalog numbers).

 

Another source is the Dynamic Range Database: http://dr.loudness-war.info/ At least you can do a quick check to see if the music/master you are looking for has a chance.

 

Here is an example walkthrough using the Police’s Synchronicity album that was recorded in 1983. http://en.wikipedia.org/wiki/Synchronicity_(The_Police_album)

 

But first aside. I happen to know the Studio Synchronicity was recorded in. http://en.wikipedia.org/wiki/Le_Studio And you know what, the actual gear does not matter so much as most professional studios have similar if not the same gear. If it was analog, Studer machines were king, but Sony (MCI) and Ampex were no slouches either. Everyone has the same compliment of mics, outboard processing gear etc.

 

Most importantly were the folks actually doing the recording, mixing, producing to get the performance out of the artist and capturing the sound. A trick I used to play on artists was to get them to run through the song a couple of times before we “rolled tape”. What the artist/band did now know what that I was rolling tape and more often than not, the first take was the artists best performance as they were excited, but relaxed as they knew the tape was not rolling ;-) In one instance, the bed tracks I recorded for a demo ended up being used on the album and both the engineer and producer could not recreate the feeling or the sound of the band at another time and place – neither could the artists. Remember, a recording is a snapshot of history that may never repeat itself.

 

Back to the Police and Synchronicity. Have a look at: http://dr.loudness-war.info/index.php?search_artist=police&search_album=synchronicity There are at least 4 masters of the same “album”. If you click on the info button on each one, you can see the details. One is the original pressing/master on A&M from 1983, another reissue on A&M in 2003, a MSFL and SACD “audiophile” versions as well.

 

SynchronicityDRCompare.jpg

 

 

What is very interesting to note is that the original 1983 pressing has the most dynamic range, beating out the MSFL and SACD “audiophile” versions. That means when the MFSL and SACD versions were re-mastered, some compression was applied and who knows what else. Also note that DR is but one evaluation criteria, but a significant one.

 

Which brings me to my point. Just because it says “hi-res” or MSFL or SACD, does not automatically mean it sounds better than the original (or other) pressing/master. This was one example to illustrate my point. Btw, you can read all about Synchronicity on Steve Hoffman forums (and others) to assist in making up your own mind without (somehow) purchasing all 4 versions yourself: http://www.bing.com/search?q=steve+hoffman+forum+police+synchronicity&qs=n&form=QBLH&pq=steve+hoffman+forum+police+synchronicity&sc=0-20&sp=-1&sk= Oh yeah, lots of discussion. Another point of eval is the recording/mixing engineer – Hugh Padgham – one of my favourites: http://en.wikipedia.org/wiki/Hugh_Padgham

 

So before you plunk down dollars on a high resolution format of whatever music you happen to enjoy, and if sound quality is really important to you, then take a bit of time to do some research to ensure you are getting what you are expecting. Otherwise, you may be disappointed. Or in some cases appalled to find out that not only has your favourite artist/band, that has been re-mastered in a high resolution format, had the snot compressed out of it, but clipping as well.

 

Best of luck!

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Newbie here, have always wondered what this Loudeness War was, and I suppose was too lazy to do a search. Well written and explained.

 

 

 

Cheers Frank

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whether we do have hires or plain vanilla editions and everything in between, we are still at the mercy of the recording engineer/mastering engineer/producer at all times, which is highly variable and still no hard and fast rule to as a guide to quality.

 

 

 

Add the overriding ruler of some bean counter controlling the VU meter settings, and there's the final product ready for release anyway! Final judgement.

 

 

 

I think there would be maybe three statements where HD tracks have stated if the original masters were used and actually named the engineer in charge.

 

 

 

This doesn't happen for every release and we have no idea really even if the mastering story was made up or the truth. Embedded in a jpg or raw file, you can, for example, add copyright information of the photographer, and it can stay with the file.

 

 

 

No such header exists that, we, the public, can see and verify for PCM audio files :

 

a) When the recording was played from the original

 

b) When the recording was mixed

 

c) Who mastered the recording

 

 

 

In the days of physical media, such information was available on the sleeves, which hopefully was accurate. With a ripped file, you really have no idea or traceability.

 

 

 

At least MFSL have a quality standard that they maintain, whether you like it or not. By quality standard I mean it's the methods and processes MFSL use to master original recordings and release a final product on SACD/vinyl or CD.

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Bob Katz, a well-known mastering engineer, has proposed an integrated system of metering and monitoring. If adopted, it would go a long way to do away with the loudness war: http://www.digido.com/level-practices-part-2-includes-the-k-system.html

 

 

 

To get an idea of the technical material covered, here is the summary:

 

 

 

"For the last 30 years or so, film mix engineers have enjoyed the liberty and privilege of a controlled monitoring environment with a fixed (calibrated) monitor gain. The result has been a legacy of feature films, many with exciting dynamic range, consistent and natural-sounding dialogue, music and effects levels. In contrast, the broadcast and music recording disciplines have entered a runaway loudness race leading to chaos at the end of the 20th century. I propose an integrated system of metering and monitoring that will encourage more consistent leveling practices among the three disciplines. This system handles the issue of differing dynamic range requirements far more elegantly and ergonomically than in the past. We're on the threshold of the introduction of a new, high-resolution consumer audio format and we have a unique opportunity to implement a 21st Century approach to leveling, that integrates with the concept of Metadata. Let's try to make this a worldwide standard to leave a legacy of better recordings in the 21st Century."

 

 

 

It is technical in nature as it is a proposed “specification”. It is also fairly complicated as it appears counterintuitive. Effectively, the idea is to turn down the level meters during recording, mixing, and mastering and turn the damn volume (i.e. monitor) up to a calibrated level! We all have volume controls :-) Here are a few practical examples: http://www.digido.com/honor-roll.html

 

 

 

There are already specifications for calibrating speaker to room interfaces: http://www.computeraudiophile.com/blogs/Speaker-Room-Calibration-Walkthrough Metering and monitoring is the last piece of the puzzle. When I was recording/mixing, I was taught to monitor (i.e. listen) at between 80 to 90 dB SPL. This was the accepted industry standard due to Fletcher Munson equal loudness curves. So to make it louder, we would just push the levels up (on the VU meters).

 

 

 

There is +26 dBFS headroom in much of pro audio gear I used as it was industry standard. During the analog tape days, it was common practice to “hit” the tape hard on some instruments as a little bit of tape saturation “sounded” like a mild compressor. Drums would sound punchier for example. Guitars would sound like they are really ripping, etc.

 

 

 

How loud can you go? Here is an example, I like the Black Keys and a tune called Lonely Boy. Here is its waveform in Audacity. It is so over leveled that it has been pushed into the red (hard clipping). I wonder if this was a mistake during the recording, mixing, or mastering process? Or is it part of their sound?

 

 

 

slamming.jpg

 

 

 

 

 

Personally, I am hoping the Audio Engineering Society, or ITU, or whatever standards body, adopt Bob’s proposal and draft it as a standard and go through the process as both professionals and consumers would benefit greatly. Then the hires audio format would really mean something. As it stands, highly compressed music material simply won't benefit from any high resolution file format.

 

 

 

Other sites of interest on the topic: http://www.justiceforaudio.org/

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