Vinyl Mastering

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Does vinyl intrinsically require a superior master than CD?

There's this idea floating around that vinyl records must have intrinsically different masterings than CDs of the same material. There's both a kernel of truth to this, and a few gigantic myths.

CDs have only one (extremely strong) restriction on how loud they can be cut - the digital peak level, 0dbFS - and (almost) anything that doesn't violate that restriction is permissible. Vinyl manufacturing has many different restrictions, and they are all rather loose, in that the restrictions can be sometimes relaxed.

   * The grooves can actually overlap each other if they are too loud. This can be alleviated by spacing the grooves further apart.
   * If the groove "moves" quickly enough - its velocity is high enough - some turntable cartridges will be unable to track the groove, and a skip results.
   * Just like the voice coils in a speaker can burn up if enough energy is dumped into them, the voice coils on a cutter head can burn up if the signal is of a high enough power. (The amplifiers range into the hundreds of watts and the coils themselves are liquid- or helium-cooled, depending on who you ask, so the powers involved here really are quite substantial.) The historical solution to this is a special limiterthat squashes the high frequencies in the music if the cutting head temperature exceeded some threshold. Clearly not a high-fidelity solution (and many mastering engineers do not use them nowadays).
   * Excessive stereo bass content (bass in one frequency or another) can compromise tracking or even make the cutting head jump out of the groove. This is sometimes solved with an elliptical filter, which sums bass frequencies to mono. Again, not all mastering engineers use this.

None of these restrictions explicitly say "hypercompressed, distorting music cannot be cut onto vinyl". Rather, that music may be more difficult to cut and play back than other music.

How many different ways can a CD master differ from a vinyl master?

# The CD and vinyl masters might just be exactly the same: the same signal that goes on the ADC goes on the cutting head.
# Acceleration limiting might be used on the vinyl master.
# Elliptic filtering (bass sums to mono) might be used on the vinyl master.
# The vinyl master may be sourced from a 24-bit version of the CD master. (However, the high noise content of vinyl generally makes this a meaningless distinction.)
# The vinyl master may be sourced from a higher-sampling-rate version of the CD master. (However, the demonstrated inaudibility of frequencies above 20khz makes this a meaningless distinction.)
# The vinyl master may be EQ'd differently to account for equalization differences in the cutting head, electronics, or playback devices.
# Finally, the vinyl master might be sourced from a master with less dynamic range compression or limiting than the CD master.

How do you know if a vinyl master is truly different than a CD master, ie, it has less dynamic range compression?

You ask the mastering engineer what he did. Other that, that, you don't know.

Some known examples: Vinyl releases with a different master than the CD

Steve Hoffman's work is generally known for distinctly different masterings compared to equivalent CD releases. His mastering of ZZ Top's Tres Hombres includes diverse changes, including a much less compressed drum track. His mastering of the White Stripes's Icky Thump is also well praised for being distinctly different (and better) than the CD release.

One known counterexample: A vinyl release with the same master as the CD

Steve Berson, Total Sonic Mastering: "When I cut the vinyl DMM masters for the first "special edition" release of the 45rpm 4-LP set for the Foo Fighters "In Your Honor" album the producers made a big deal out of wanting to have an "audiophile" release and made sure that I could work from 24bit/96kHz source (which I was able to do at Europadisk due to SAWStudio sending to a matched pair of Lavry Blues that went to both the pitch depth computer and the cutting head) and that I did as close to a flat transfer from these as possible. I was disappointed to find that the high res files I received from Bob Ludwig for the most part had been heavily clipped as they were the same files (just prior to SRC and dithering) that the CD master was made from. "