Problem with True Peaks (is it Limiter6 or Reason DAW causing issue?)

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Tempo Fugitive

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Hello, I'm wondering if any one can help me with an issue I'm having after Mastering a track.

I'm using Reason 11 as my DAW. I have the Limiter6 plugin for brickwall limiting (with ISP Protection on---set to Precise).

At the end of my mastering chain, I have the Youlean Loudness Meter. It tells me my True Peaks are at -0.9 db throughout.

I export the song to Audio (i.e. 16 bit .wav file with dithering & 44.1k sample rate).

Then I open a new instance of Reason and import the newly mastered .wav file in. I put the Youlean Loudness Meter on the master effect chain (and nothing else), and it reads True Peaks in the +2db to +3db range!

I don't understand how this can be happening?

I posted this question on a Reason specific forum, and I was told that Reason is bad for mastering (with the only explanation being that you cannot trust its built-in metering, but I'm not using any of its metering----I'm using Youlean Loudness Meter).

So I guess I'm not sure what I should do.

Does anyone have experience dealing with this type of problem?

Could it be that Limiter6 (free version) is not a good Limiter?

Or could it be that Reason is in fact a bad DAW for mastering?

Sorry if that was a long read, but any help would be appreciated! TIA!
 
Hm, that is odd. I think just going from some other sample rate to 44.1 kHz can make the TP shift slightly, but not several dB. I think I'd load Reaper and experiment to see if it gives a different result. You wouldn't have to apply a full mastering chain, just load a file, measure it, export it then load it in a new project and measure it again.
 
Can you load the file into a different editor, such as Audacity or Reaper, and look at the peak tops to see if they are flat topped at the points that are +2dB? Theoretically, you cannot have a +2 or 3dB peak if 0 is defined as 2^16. There simply are no bits remaining.
 
TalismanRich said:
Can you load the file into a different editor, such as Audacity or Reaper, and look at the peak tops to see if they are flat topped at the points that are +2dB? Theoretically, you cannot have a +2 or 3dB peak if 0 is defined as 2^16. There simply are no bits remaining.
Click to expand...
True, but "True Peak" is a calculated level that models the output of a DAC. It can exceed 0 dBFS, especially with clipped or heavily limited digital signal. If TP is going over 0 dB, the waveform is almost certainly clipped or at least heavily limited.
 
Ok, thank you both for the suggestion! I shall give it a try...
 
Ha! I discovered the problem!

When I opened my DAW to listen to the master, I forgot to change the tempo to match the imported audio file. As soon as I changed the tempo to the song, the True Peaks dropped to no more than +0.1 db (which seems acceptable to me).
 
That's good, but TP over 0 should be avoided. A bit under 0 is best. The reason the standard is -1 dB is that converting to a lossy format can raise them, and starting at -1 makes it pretty unlikely to end up over 0.
 
bouldersoundguy said:
That's good, but TP over 0 should be avoided. A bit under 0 is best. The reason the standard is -1 dB is that converting to a lossy format can raise them, and starting at -1 makes it pretty unlikely to end up over 0.
Click to expand...
Ok, I have to redo it anyway. I noticed something wrong with the mix, haha!
 
if you are planning on making MP3's off of your mix,
you had better shoot for about -0.5db minimum for TP.
 
Headroom at -0.5 dB might be adequate, but most of the LUFS standards specify -1 dB.
 
i've seen zero professional releases that had a true peak of -1.0 dbfs.
if anything, almost all of them peak over 0.
 
I'm a bit confused now - why does the tempo have any impact of a volume measurement? Have I missed something critical about the new fangled was of measuring levels?
 
rob aylestone said:
I'm a bit confused now - why does the tempo have any impact of a volume measurement? Have I missed something critical about the new fangled was of measuring levels?
Click to expand...
I don't think it does, normally. That's part of the mystery in this case.
 
GONZO-X said:
i've seen zero professional releases that had a true peak of -1.0 dbfs.
if anything, almost all of them peak over 0.
Click to expand...
I think that's highly dependent on genre and era. I just grabbed a CD that was on top of a stack of them in a box, Bob Dylan's Blood on the Tracks, and imported a random song, which turned out to be Idiot Wind. The TP is -3.6 and the LUFS is -16.9. I do recall looking at a QOTSA CD as a reference for a mastering job I did a few years ago. It was severely flat-topped. I've also experimented with pulling down audio like that to get the TP below 0, and it had an audibly beneficial effect. The digital clipping was less of a problem than ballistics that send the waveform over 0. That effect probably depends on the converters being used.
 
I think it's depressing that we went from a format that was pretty limited in dynamic range (S/N usually in the 60dB range) and limited channel separation (typically around 20-25dB at 1kHz) to CD which should easily reach >90dB S/N and channel separation with dithering, then we compress the living shit out of the program data and complain about CD being "squashed" and having bad sound. There's no reason we shouldn't be able to reproduce an original 1st generation master tape with full range.

If a CD sounds compressed, I say it's the fault of either that original producer or the mastering engineer who decided to smash it to make it sound as loud as possible, rather than using that dynamic range to reproduce the full range of the original source.
 
I remember buying the CD of Iggy Pop's "The Idiot," which I only listened to on vinyl up to that point. I was very familiar with that record. A really good sounding record. So I was shocked, to say the least, when I played the CD. Dull, flat-sounding, wretched. Apparently it was not re-mastered properly for CD, or something. Same goes for King Crimson's "Court Of The Crimson King." The CD version is unlistenable--noisy, crappy-sounding, flat. I do know that that record was properly re-mixed and mastered for CD a few years ago by Steven Wilson of Porcupine Tree, and that's a recording I'd like to get. Wilson also did Yes' "Topographic Oceans" and Jethro Tull's "Aqualung" along with many other titles. The original records themselves were often not in the best shape sonically, so CD transfers likely showed every flaw, magnified (like tape hiss). Anyway, I do know that inthe early days of CDs, they often weren't transferred properly.
 
That goes to show that "professionally mastered" doesn't always mean much.
 
rob aylestone said:
I'm a bit confused now - why does the tempo have any impact of a volume measurement? Have I missed something critical about the new fangled was of measuring levels?
Click to expand...
Either it’s resampling to maintain the original pitch which is literally resynthesis so that it’s not even the same audio to begin with, or it’s playing back at a different speed and you’d hear a pitch shift because every frequency gets shifted. Either way, we’d expect the weird math that generates the completely imaginary and hypothetical TP numbers to work out different from when it was played at the correct original tempo.
 
But surely, level is a simple measurement of the level at one sample - so each sample, no matter what the rate is, has a value. If that value is every bit on, then that's 0dB? If you have a hardware machine with varispeed, turning the knob speeds up or slows down the pitch - but the volume stays exactly the same? It can't have a link to tempo as everyone would notice if a 120bmp track was louder or quieter than one at 90? Something very weird is happening here?
 
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