DAW: Reaper
Pan law: 0.0dB
Master FX: just Sonible smart:limit
Monitoring FX: just Sonible true:level
Master volume: 0.0dB.

smart:limit is set to have a limit of -1.0dB, as seen in the screenshot:
https://i.imgur.com/4HedCbu.png

Throughout the entirety of the song, the TP value on the meter on the right in smart:limit will never go above -1.0 dB, which I'd expect. That value shows "TP" (true peak) below it, but I wonder if I'm misunderstanding its meaning here.

I have some other metering that seems to show the true peak value at anywhere between -0.3dB and -1.0dB. Frequently closer to -0.5dB. Why is that? Why wouldn't it be -1.0dBTP (or close)?

The metering tools that I'm using are Sonible's new true:level, and the master meter in Reaper. The latter is set to read true peak at the top of the meter, and it often hovers around -0.5dB ish. Here's a screenshot of the meter settings:
https://i.imgur.com/zkMiP78.png

Here's what Sonible true:level shows:
https://i.imgur.com/vN5ys4D.png

I've turned off all monitor FX to ensure nothing is adding anything to the sound, and I've even set all the values at the bottom of smart:limit to 0s (Style, saturation, balance, bass control) and that didn't change anything.

Why would the limiter show maxing out at -1.0 dBTP, but the other meters show about 0.5dB higher, very frequently?

The temp solution I have is to just throw ReaLimit after smart:limit, and set ReaLimit's threshold to -1.0db, brickwall ceiling to -1.0dB, and check true peak. Then master meter will max at -1.0dbTP and true:level will max at -0.9dBTP, which seems close enough to me.

Am I doing something wrong or misunderstanding something?

 

How does it sound to you?
Does it sound better or worse?

 

Yes, I've seen this as well.
I think it's better to use RTW or pinguin for metering analysis anyways.
However I think it's a usuable tool to quickly check dynamics. I just wonder after what reference material the dynamics advice is evaluated.

 

Last edited: Nov 11, 2022

Because dBTP is not really True Peak, but Oversampled Peak. It depends on how often the detector is oversampled for measurement (or limiting). Anything from or above 8x OS is quite meaningful. And then there is the question of whether the decimal place is rounded up or down. Normally, people round up, but in the audio industry hardly anyone adheres to any conventions anyway. So much for "why?"
What you do with the information is your beer, as they say.

Edit:
Is your Master fader @ unity?

 

Last edited: Nov 11, 2022

Thanks for all that info.. I have much to learn. lol I think I'm confused by dBFS vs dBTP vs TP. And yes, the master fader is at unity.

I would have been kind of oblivious to any of this and just continued on as normal if I hadn't put true:level on my monitoring FX and saw it say that I should reduce the peak level by x dB. That's when I saw the "problem" (in quotes because it maybe is only a perceived problem).

Initially, my master meter was also set to display in dBFS. It would just show peak level at no higher than -1.0dB(FS), as I expected (due to the threshold in smart limit being set to -1.0dB), but I was confused as to why true:level showed a somewhat significantly higher value - as high as -0.3dB. It was the "reduce the peak level" message in true:level that made me then change my master meter to display in dbTP.

So, then I just wondered why if smart:limit showed -1.0 "dbTP", but the master fader's meter and true:level both showed even as high as -0.3dBTP (I'd say it hovered frequently around -0.5ish dbTP). Is this due to the amount of oversampling these two tools use vs. smart:limit? (presumably a lower amount for smart:limit)

Follow up question, if I'm concerned about streaming services here, should I be checking the peak level in dBTP, or should I check it in dBFS? I assume the former, based on the message being shown in true:level.

Assuming dBFS is correct, should I use a true peak limiter with high oversampling, like Fabfilter Pro-L 2 to achieve that? Could I first just use smart:limit to ballpark limiting (I like how it makes some decisions for me), then have Fabfilter Pro-L2 do a light bit of limiting after to ensure I don't peak over -1.0dBTP? Or is there a smarter / more common way of doing things? I know I can just use Fabfilter Pro-L2 on its own, but again, I like how smart:limit makes some decisions for me.

Yah, I figured a 0.1db difference, give or take, was fine, but at points it gets to be even 0.7dB, which seemed wrong to me, but I guess that was just my own confusion in the different types of peak measurements.

Yes, that was all I was concerned about, thanks.

 

Last edited: Nov 11, 2022

Well, I would say do what you feel most comfortable with.
Multi-stage limiting is a good option.
Relying only on the Sonible limiter is as well.
If there are just a few samples that the Sonible limiter misses, you can also manually lower the samples afterwards in an audio editor. At least this is the most transparent option.
But to be honest, who cares about the -1dBTP streaming convention? There's nothing wrong with sticking to it, but as I said, hardly anyone does. I don't unless the client explicitly requests it, which is rarely the case with music. I usually give the material about 0.3 dB of headroom. Sometimes I deliberately clip the output if the sound and dynamics of the material fit and the transients can be clipped evenly over the entire track. The clipping is then always only a few samples at a time, but that's another story. If your peak is higher than the streaming provider wants, your material will be normalized accordingly by the streaming provider anyway.... well, or not.

Sorry, I'm probably not the best help for you right now, am I?
I hope you can still pull out one or two useful things for yourself.

 

@No Avenger Yah SmartLimit seems to be measuring differently, agreed. Weird that SmartLimit and Truelevel are both by sonsible but measure differently in spite of both displaying as "dB TP", but I think I may just use a couple limiters.. Smart limit to get me in the target loudness range / and another one lightly limiting and ensuring things are below a target dBTP. I won't worry about it too much though based on @Sinus Well 's advice.

@Sinus Well actually you've helped me a lot. The answer I hear, and needed, is "don't sweat it." And that's what I'll do.. Not worry so much about it... Go back to being oblivious. Lol thanks for the advice / info.

 

Last edited: Nov 11, 2022

I find these "smart" range of plugins hit or miss (more times miss) and kind of wonky in their visual feedback, but they do occasionally sound good so theres that.