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Why do all (by all I'm speaking from my personal experience thus far as well) the eighties LPs measure almost exactly the same as their CD counterparts? Both are equally dynamic but for some reason always have pretty much the same DR "value" as one another.

...these records should, in theory, be "scoring" 3-4 dB higher on that meter as well. The records have the same issues of crosstalk, soundstage, etc. that we're taking Ian's word is changing the the "value" of his own recording.

I believe it's the lack of excessive compression (or lack of excessive compression).    If you take an "pure" uncompressed recording of an orchestra and run it through an all-pass filter, the DR "measurement" or crest factor should be unaffected,  because all of the frequency-components sum-up randomly either way.   

But a compressed/limited file has been limited wherever the frequency-components "randomly" sum-up to exceed the threshold/limit.    When you all-pass, the timing of the various frequency components is "randomized" again...

Why does anyone use the TT DR Meter? Where is the algorithm specified? Why isn't it based on BS-1770?

My thought regarding the TT meter : ok , a big DR value isn't a warranty that the record has a good dynamic range.
However I think the reverse is true, a too low value (let's say below 6) indicate that the dynamics has been too much squashed.
So the TT meter is still doing it's job to some extent.

up to 4dB "error" or uncertainty.

Quote from: xnor on 2013-10-07 21:09:23

Why does anyone use the TT DR Meter? Where is the algorithm specified? Why isn't it based on BS-1770?

there was a link in that thread at one point to a brief white paper describing the TT Meter's workings....not code though, if that;s what you mean.

My thought regarding the TT meter : ok , a big DR value isn't a warranty that the record has a good dynamic range.
However I think the reverse is true, a too low value (let's say below 6) indicate that the dynamics has been too much squashed.
So the TT meter is still doing it's job to some extent.

If I have a CD at DR5/6 and a vinyl rip at DR11/12, can they really be the same master?

Quote from: pisymbol on 2013-10-09 05:28:38

If I have a CD at DR5/6 and a vinyl rip at DR11/12, can they really be the same master?

Ian Shepherd's video is talking about a specific situation:

The same peak-limited master as was used for prepping the CD/digital releases was also given to the vinyl mastering house, where it was then subjected to an unknown amount of additional processing that's required for putting audio onto playable vinyl.

At the very least, presumably, the bass was made more mono, and bandpass filtering was applied to roll off frequencies outside of the 30 Hz to ~20 KHz range (maybe not even that high). Either of these things alone can increase the measured DR value, effectively acting as an expander, reintroducing a few dB of "peakiness" to the audio. So whether you consider the vinyl master to be the "same" depends on whether you're taking this into consideration.

And that's only talking about what audio goes onto the wax. When you rip it, you're introducing many more variables and slight changes to the audio via your particular playback and recording system, which can nudge the rip's peak-to-RMS ratio in one direction or the other. All together, a ~6 dB difference in the measured DR value probably isn't out of the question.

I'm trying to understand WHAT is causing spurious peak variations to offset the DR?

Quote from: pisymbol on 2013-10-09 13:08:08

I'm trying to understand WHAT is causing spurious peak variations to offset the DR?

An all-pass filter makes the peak value of a clipressed digital master jump up by about 3dB, and doesn't change the RMS at all - hence the measured DR value "improves" by about 3dB.

A phono cartridge and complimentary RIAA filtering are (at best!) an all pass filter (plus some attenuation of the frequency extremes, plus complete blocking of DC, plus hopeless response at very high frequencies, plus distortion, plus noise etc etc ...).

Cheers,
David.

Why is this metric even being given any credence in the first place?

With this in mind and since people will keep using these tools could there be any merit to implementing a BS 1770 loudness range version of foo_dynamic_range?

up to 4dB "error" or uncertainty.

ran it through Audition's subsonic rumble filter

However I think the reverse is true, a too low value (let's say below 6) indicate that the dynamics has been too much squashed.

Quote from: DVDdoug on 2013-10-08 22:45:07

up to 4dB "error" or uncertainty.

For giggles I took the CD version of the file found here and ran it through Audition's subsonic rumble filter with 6dB of attenuation to prevent clipping.

The DR value jumped from 5 to 10.

EDIT: I bumped the treble a little bit in an attempt to more closely match the vinyl version and the DR value increased to 11.

Quote from: DVDdoug on 2013-10-08 22:45:07

up to 4dB "error" or uncertainty.

For giggles I took the CD version of the file found here and ran it through Audition's subsonic rumble filter with 6dB of attenuation to prevent clipping.

The DR value jumped from 5 to 10.

EDIT: I bumped the treble a little bit in an attempt to more closely match the vinyl version and the DR value increased to 11.

[blockquote]Q: These days, many independent productions are completed at home in project studios. What can mastering offer to enhance the final sound of these projects?   

A: Often home productions are recorded and mixed under less than perfect acoustical conditions. I can make educated decisions and offer options to the producer that will translate well to the real world. My experience allows me to make major or subtle changes, while working in conjunction with the artist, producer or label, which really can improve the final sound of any project.[/blockquote]

....Neumann's name became attached to the correction because its lathes—on which a great many of the world's vinyl records have been cut down the decades—have been reported to incorporate an additional record EQ time constant of 3.18µs (50.05kHz). As we will see, this isn't correct....

...

...

ran it through Audition's subsonic rumble filter with 6dB of attenuation to prevent clipping.  The DR value jumped from 5 to 10.  EDIT: I bumped the treble a little bit in an attempt to more closely match the vinyl version and the DR value increased to 11.

I'm wondering if multiplying "%replaygain_track_gain%" and  "%replaygain_track_peak%" datas ,
doesn't provide a more reliable information about the dynamic range, than with  the TT Dynamic Range meter .

Quote from: extrabigmehdi on 2014-04-03 12:03:55

I'm wondering if multiplying "%replaygain_track_gain%" and  "%replaygain_track_peak%" datas ,
doesn't provide a more reliable information about the dynamic range, than with  the TT Dynamic Range meter .

I've been interested in a sort of "ReplayGain Database" for a while now... It would be better than the DR meter for vinyl rips, right?