Friday, 14 March 2014

Recalled Article on Vinyl Rips and High DR...

Hey guys, I "recalled" an article I posted this AM on why DR increases with vinyl rips based on RIAA EQ processing.

The reason being I think small changes like +2-4dB of DR in compressed recordings using the RIAA EQ are very much based on the resolution of the emphasis and de-emphasis filters. JR_Audio made a comment on this and I had a look at the accuracy of the RIAA curves I made. Indeed, mathematically essentially perfect curves <+/-0.1dB add very little DR extension, maybe only 1dB whereas "looser" accuracy like +/-0.5dB through the audio band could give +2dB with the DR Meter with some idiosyncrasies depending on the song and which frequencies the RIAA inaccuracies lie.

The problem is that these are simulations done on a computer with accuracy of 32-bits. As I said in the original article:
In real life, things are more complicated. Even without a significantly better source master, for the final vinyl mix, small changes can be done to the signal such as mixing all the bass frequencies up to 100Hz into mono or taming of the high notes along with the RIAA curve. The results might be more pleasing or euphonic (see this article on mixing for vinyl and how much work potentially needs to be done). On playback, other physical factors are also involved such as the tracking force of the cartridge/tonearm or idiosyncrasies of the cartridge and accuracy of the phono pre-amp. Also, post-processing such as noise/click/pop reduction would add another variable for the results from "needle drops". If you look at a number of different vinyl rips, it's quite common to see slight DR variation depending on the equipment and technique used (typically another DR +/-1dB is not uncommon).

Indeed, I noticed this afternoon playing with Audition just how easy it was to artificially inflate DR values! For example, mixing all low frequencies <100Hz as mono. I played around with this using Lorde's Royals song using a lowpass filter to isolate those low frequencies and then mix them back into the highpassed upper portions as mono... Even though the sound wasn't significantly different when volume matched, it was not difficult at all to get a DR8 original 24/48 HDTracks version up to DR13. As I noted in the original article, I believe this is just the result of removing peak limits and clipped portions, allowing the calculations to extend these portions with the DSP operations.

Given the effect I saw, ultimately I think there's no conclusion one can draw between what's measured on a vinyl rip and knowledge/proof of whether truly new masters are being used unless specifically told about it!

I guess after trying this for awhile, I realized just how sensitive the DR Meter can be. Ultimately it is useful as a tool to explore the average dynamic range of albums and especially pick out very poor masters with strong peak limiting. It's also useful to determine if 2 pressings are exactly the same.

Anyhow... I might review this later if anything clears up for me in the days ahead; just really hard to post something unless good conclusions can be reached.

I'll leave you with the last bit of the post however...

Parting example:
One example of a vinyl remaster that's truly the "definitive edition" is Stadium Arcadium by the Red Hot Chili Peppers. As usual for Vlado Meller the CD's mastering engineer, the dynamic range compressor was stuck at "11" resulting in a sick album with an average DR5. The vinyl release had proper mastering treatment by Steve Hoffman resulting in a DR12 average. That's the kind of difference one wants to see between CD and vinyl to be sure of truly better vinyl source material.

Have a good weekend everyone. Now go enjoy the music and the weekend... Careful about the Pono droppings this week. :-)

Speaking of Pono, check out all the new "limited edition" Pono players you can get on Kickstarter today with one's favourite band named on the unit! Wow, looks like they're going all out on moving as many virtual units as possible sight-unseen except for a few pictures and ear-unheard... It'll be interesting to see what the final product reception will be like when shipped. (I'm also very curious about the objective measurements!)


  1. Hi Archimago

    In my experience, the most influence between the DR range of PCM and Vinyl releases is indeed the preparation of the source file to the limitations of the Vinyl pressing and here especially the mono making function of the bass region. I therefor use the BX Digital V2 plug in from Brainworx. And this that, I can prepare the mix for Vinyl in a way, that at the end, I have about 2 - 3 dB more DR reading.

    Similar thing must have happen to the "Beck" files. Because when analyzing the vinyl mix I have noticed, that mainly the kick drum and the bass notes stood out of the otherwise plain limited PCM mix. So the mono maker or in more general the stereo width has a great influence in how the DR meter shows up, but the DR meter is right in his function and just does give you the numbers, what you can see in the wave file.


    1. Indeed. Thanks for the input Juergen. I've not tried the Brainworx plug-in. I was blown away by just how much difference rather small manipulations could make so long as I lowered the level of these audio files prior to various plug-ins manually!

      I could see some easy ways for companies to boost those DR numbers even if the source material is highly compressed... Shhhh, hopefully they won't do this to cater to those peeking at DR numbers! :-)

  2. I don't know why anyone would use the DR meter. The algorithm sucks. It's broken.

    Use BS.1770 based meters instead!

    1. Convenience and easy availability I guess...

      I haven't looked into this xnoreq. Are there convenient, simple plug-ins freely available for this?

  3. I recently investigated a DR 'anomaly' in a CD release of Sky's self-titled debut album. There have been a number of CD reissues of this album but one in particular (MER008 on the Merlin label) apparently has higher DR levels than all of the others. When I finally found a copy it turned out that it was indeed more dynamic according to the DR meters but only because the EQ has been altered with the bass cut and the treble lifted. It sounds positively awful compared to my Ariola CD (250 589). I then tried some experiments using SoX to see if I could reproduce the effect myself and sure enough it was very easy to artificially increase DR through fairly subtle EQ changes. I don't think for a minute that the Merlin release was altered deliberately to increase DR but it makes me cringe to think that anybody might regard it as the definitive CD version of the album (based on the DR results) when in fact it's by far the worst I've heard. A lesson well learned for me.

    1. Good observation Stephen.

      Indeed, I'm realizing that the DR value itself isn't the most important thing so long as it's reasonable (like DR>8 or so). The only thing useful about the DR is if it's correlated with a clearly overcompressed waveform. As you say, it appears very easy to artificially boost with a bit of DSP'ing.

      Nonetheless, there is some correlation with sound quality in that DR<5 will pretty much suck! :-)

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  5. EDIT: turning autocorrect on sometimes goes wrong :)

    Speaking of Pono!

    Check this Neil's NPRmusic interview.

    No facts at all, but you have to admit good marketing (reminds me of rejuvenation creams with 27% efficiency).

    Q: What do you get with Pono?
    A: Youth!!

    Some old people think they are deaf, but they are NOT. It is because they listen to mp3's and CD's!

    Maybe his original idea wasn't that bad (good to spread the word), but seems to me that he lost it to financial, and marketing ideas.

    This sounds like a joke:
    Q: Why your live performance sound's that great, and when it's loud I don't need earplugs?
    A: We run the show on 192, or the very lest 96, but we don't like 48!!!
    Says Neal :))) hahahaha

    Pono is a must have!
    Just cant decide which limited edition Signature Series PonoPlayer to choose: Beck, Metallica, Red Hot Chili Peppers, Pearl Jam or Arcade Fire…..
    They all deserve at least 24/192 download! Anything less than that would be audiophile heresy.