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Topic: dB to dBFS conversion

Hello,
I have a client who would like the decibel level on a gain control to be displayed using dBFS rather than the analog scale.  Looking for suggestions on how to accomplish this.

Also, just curious as to why the analog scale is used in nWare.  I have been working with Media Matrix systems for a long time and the subject has never come up; however, with the proliferation of digital mixing consoles, more people are expecting their digital devices to use the digital scale.

Thanks,
JRG

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Re: dB to dBFS conversion

Hi JRG,

It is actually REALLY EASY to change the meters from the standard NWare meters to make them reference full scale.

The standard scale of the basic NWare meter has values set at: 35:20:10:4:0:-2:-6:-10:-15:-25:-35
If you wanted to change these values to what is referred to as "Full Scale" the values would need to be changed to: 0:-15:-25:-31:-35:-37:-41:-45:-50:-60:-70

This can be done with the assistance of Inspector.

To start with, you need to have Inspector enabled in your NWare installation. It is easy to turn on, simply go to Tools>User Preferences>Advanced and you will see a check box that allows you to turn on Inspector (it says "Show Inspector (requires application restart)". Yes, after you enable Inspector you will need to shut down NWare and restart it. After restarting NWare, you may notice that the Utility Frame now has another tab that says "Inspector".

On the Inspector tab, you will notice that the list of options change depending on what you have selected in the Design frame. You should be careful what you edit in the Inspector. However, when you select a meter you will notice that there is a field called "ctl_options". On a meter device, these ctl_options are the numbers that represent the values displayed on the meter device. You can double click in the "value" column and edit these numbers directly.

Pro-Tip: You can copy the list of values I provided above and paste them directly into the ctl_options field. Sha-zam! You just rescaled the meters!!!

Josh Millward
Burnt Orange Studios

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Re: dB to dBFS conversion

Josh,
That is quite simple for the meters.  However, I am looking to scale the actual control knob so that the user input and displayed value of the knob are in dBFS.

Thanks,
JRG

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Re: dB to dBFS conversion

Then I'm a little confused, JRG... can you give a bit more specific of an example?

I just really don't understand why someone would NOT want to know what dBu level will drive the system to full scale. This is essentially what the actual input sensitivity controls tell you. You set the control at 18dBu and it takes a signal of +18dBu to drive the system to full scale. Likewise, set it to -42dBu and it takes an input signal of -42dBu to drive the input to full scale. This is because we are actually scaling the input sensitivity of the analog inputs.

So, I'm a little confused about exactly what you are looking for.

Josh Millward
Burnt Orange Studios

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Re: dB to dBFS conversion

Josh,
This is not for the analog input or output gain on the NioNode, this is for a Gain Block in the DSP chain. The client wants to set the gain knob to a dBFS value e.g. -20dBFS instead of a dBU value e.g. 0dBu.  The system has all AES inputs and outputs, so the systems they are connected to all show their values in dBFS.

The other equipment is set to reference -20dBFS = 0dBu.

Thanks,
JRG