What fader position for 0 dBFS on AES?

[MartinMParticipant]

Hey, all! I have a stereo matrix that sends audio to our stream, and I have an insert on that buss that goes into Waves SuperRack. I use a series of plugins to get the signal very close to 0 dBFS, with Waves WLM Plus level meter as the last stop, using the YouTube preset. That signal then leaves on an AES output and goes into an AJA FS2 audio embedder, and then on to the encoder.

Where should I have the fader positioned in order to neither increase or attenuate that level? I’m asking because it seems like having it at “0” (unity) is sending a level that’s less than 0 dBFS.

Thanks much!

Martin

[RSParticipant]

0 dB on the dLive fader equals -18 dBfs, according to the manual.

[msteelParticipant]

@martinm
What are you using to determine that it is coming out of your plugin chain close to 0dBFS, and what are you using to determine that it is less after the fader? And how much less?

So far I haven’t found the -18dB value @RS mentioned anywhere in the manuals. I do see that 0db on the meters is +4dbu analog, and the maximum output is +22dbu. Those in combination indicate that 0db on the meters should correspond to -18dbfs. However, but that is the meters not the fader. (And then there are the technicality questions about whether the meter ballistics are sample peak, true peak, RMS, or some other thing).

I also see in the manual where there are “analog” and “digital” settings for the inserts, but my reading of the manual seems to indicate that those affect the insert send level and not the return – so in your case it doesn’t seem like it would be what you are looking for.

Intuitively, the fader at 0db should mean just that, 0db gain. It appears from the block diagram that the matrix inserts are followed by several other blocks in the processing chain, so make sure there is not a gain change in any of those. The block diagram also shows a global meter setting. It might be helpful to try changing that setting to see what your master meter looks like post-insert, post-eq, post-comp, post-fader, etc.

Also be alert to the possibility of errors or inaccuracies in the block diagram or manuals. I have seen those before in other equipment at least 🙂

[Anonymous]

I’ve always the same problem: Most Consoles provide a Level at 0dB (Meter) on Digital Outputs like Dante, AES or Madi of -9dBFs = analog +4dBu (this is a normed Level for Digital Sources) see AES convention.
Not so A&H: 0 dB on the dLive fader equals -18 dBfs.
So if we connect the A&H to our broadcast mixers (per SuperMadi) we have to add 9db of Digital Level for the expected input Signal.

Other Companys have the exact leveling on Digital I/Os: If I use old Virtual Soundchecks from Other Consoles on the dLives we had to trim down all Inputs.

That sucks for Years, because in Broadcast Business we are working with fixed predefined Levels as described, but love the Features of the dLives!

[Miasm1Participant]

Hello Martin,
The fader should ideally be at “0” (unity) for neither increasing nor attenuating the level. However, since you’re experiencing a level less than 0 dBFS, you may need to check the signal chain’s calibration, including the Waves WLM Plus settings, to ensure everything is aligned properly.

[RohanParticipant]

Hi Martin,

To avoid clipping in your digital setup, adjust the fader slightly above 0 if it’s sending a level lower than 0 dBFS. Check individual plugin gain, use the WLM Plus as a guide, and monitor output levels closely.

Regards

[Anonymous]

Dear Martin!
As I explained above normally You can’t reach 0dBFs = Digital Fullscale without any Headroom. Because the Fader adds 10dB max above Unitiy Fader Point. Internally the Mixer provides -18dBFs +10 from the Fader is -8dBFs if Your Input is not to high or clipped!!!!! If You send a sinus (Meter shows 0) and You add near 9dB on Your Fader, Your AES Output will send -9dBFs and this is the Normal Level for an AES Output with 9 dB of Headroom because the Level ist 9dB under Fullscale.

So the point is: Which Gear will be connected on the digital AES Outputs and what Level will be expected from that equipment. If You work with standard AES equipment the output of the dLives will always be too less. Perhaps You can try this with an Amp with AES and Analog Inputs. Analog should be much Louder…. if there is no other preamping in the chain.

Regards

[RSParticipant]

@Samohtant, not sure where you will end up trying to start a conversation about this with a bot….

[RSParticipant]

Was talking about Miasm and Rohan…
Didn’t get your answer wasn’t related to them in the first place, sorry.

[Author]

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