Yes, spelling was never my strong suit.
By the way, my reference to dynamic range is regarding musical content only. For realistic-sounding
recordings in real environments, the noise floor from peak level can be in excess of -70dB, but all
of the "golden age" records we like so much had an effective range from LP surface noise to peak
level of 40dB or less. Master tapes from that era had at best a 60dB dynamic range from his floor to
1% distrotion in the electronics or tape saturation, whichever came first (this depended on the tape
formulation, nominal operating levels and the frequency spectrum of the peak information).
Bottom line, the biggest crock ever is "90dB dynamic range" -- that's a useless number representing
a useless idea. Plus, given the switching distortion that takes place in the low-level digital bits,
it's doubly useless in the digital age. Dither was invented specifically to avoid true 90dB dynamic
range, so the low bits don't audibly switch off to digital black.
-- Tom Fine
----- Original Message -----
From: "Louis Hone" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, October 19, 2012 10:30 AM
Subject: Re: [ARSCLIST] Analog to digital dBFS standards
You wrote *"**unless it's made in an anacholic chamber"*
I think you meant "anechoic".
An alcoholic chamber is where they used to record Dean Martin :-)
2012/10/19 Tom Fine <[log in to unmask]>
> Hi Henry:
> My rules of thumb when transferring from analog sources:
> 1. don't overdo levels at any stage of the analog chain. Know your gain
> stages, know your headroom on all pieces of equipment, work accordingly.
> 2. always transfer at high resolution, 96/24 seems to be the resolution
> specified in most grant-funded projects on which I've worked. I believe it
> is the standard specified by NARAS. Working at 24-bit allows you to be
> conservative with ingestion levels.
> 3. since almost all DSP effects ultimate digital levels, you want to leave
> plenty of headroom in your raw ingestion file. I never go above -6dBfs peak
> level, and usually stick well below that. I am conservative with DSP, so
> I've never had a problem where something like NR, EQ or tick and pop
> removal brings the peak level anywhere near digital zero. If you're more
> heavy-handed, give yourself more headroom to be safe.
> 4. final "master" product should be peak-normalized. There has been some
> controversy about this over the years, mainly because cheaper-design CD
> players' post-DAC analog stages have no headroom and thus audibly distort
> before digital zero, plus there are problems with "rips" to MP3 and other
> lossy formats. Being conservative, I normalize peak levels to -1dBfs for
> non-dynamic content (ie rock music) and -0.5dBfs for very dynamic content
> (ie well-recorded classical music). There were some "toothpaste-compressed"
> analog products back in the day, especially rock albums late in the LP era.
> Those sources are best normalized to a peak level of -2dBfs so they seem a
> little bit less "super-loud" when played back with other material or
> combined into iPod playlists. They'll still seem "too loud" compared to
> well-produced audio.
> So one question that comes up in all of this is "what is 0VU on my console
> as far as dBfs in my DAW"? Assuming 0VU = +4dBm, and you have your mixing
> console set accordingly, I think you're safe with 0 = -12dBfs, but I think
> one more conservative standard out there calls for 0 = -14dBfs. I can't see
> how that hurts in a high-resolution digital environment, so nowadays I'd
> advise go for the more conservative standard. In reality, there is NO
> content that's really "90dB" unless it's made in an anacholic chamber, and
> no one would want to listen to it. The best classical music has about a
> 30-40dB dynamic range as far as audible ppp to audible fff (yes, it's
> possible to get 60dB in a good quiet venue using digital recording, but
> very few listeners will be able to hear that without riding the volume
> control). Well-recorded jazz can be in the 12-15dB dynamic range, sometimes
> a bit more. Rock music rarely has dynamic range of more than 6dB ("half as
> loud to twice as loud"). Toothpaste-mastered stuff literally has less than
> 1dB dynamic range, it's just an annoying onslaught of sound.
> I'm interested in other comments. Are others operating under very
> different rules of thumb?
> -- Tom Fine
> ----- Original Message ----- From: "Henry Borchers" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, October 19, 2012 9:51 AM
> Subject: [ARSCLIST] Analog to digital dBFS standards
> Hello all,
> I've been hitting a brick wall with my research and I was hoping that with
> all the experts here, someone could point me in the right direction. Iím
> currently looking for research done on digital reference levels. I am
> particularly interested in looking for references related to the amount of
> headroom standards digital audio archivists and audio digitization
> technicians use in their digital masters and the digital level dBFS that
> analog equipment have been calibrated to. Iíve been able to find a lot of
> references about dBFS standards when it comes to audio for DVD, TV, and
> cinema (such as SMPTE standards) but not much for the digitization of audio
> only content. I have been having trouble locating good research regarding
> this area and I was hoping someone here could point me in the right
> Henry Borchers
> Broadcast Media Digitization Librarian
> University of Maryland
> B0221D McKeldin Library
> College Park, MD 20742
> (301) 405-0725
*sent from my ringing donkey*