P16-M Gain Staging information

[nmalexandersen]

Hello All

I am confused with regards to the Gain Staging on your P16-M personal monitor mixer

I have full control of the levels on my x32, so I know what the levels are when they are entering the Ultranet system.

So the questions goes like this

What is UNITY GAIN setting for the Channels Volume & Main Volume?
or is it only an attenuator?

What is the “ballpark” UNITY GAIN setting for the is the OUTPUT LEVEL pot?
Or is this also only an attenuator?

If I have 18 dB of headroom on my X32 when sending a signal out through Ultranet, I need the P16-M also to have 18 dB of headroom available.

I am connection the outputs of the P16-M to an IEM system, so I need to know how to avoid internal clipping inside the P16-M. At least I need to be in the ballpark with regards to gain staging.

Regards Nils M Alexandersen

[pvannatto]

Hi Nils @nmalexandersen , I wouldn't be too concerned about clipping on the P16M. We've been using 6 P16M at my church since December 2012 and we've never encountered a clipping issue. Regarding your question about unity gain, as far as I remember, there is no specific setting on any of the knobs for unity.

[nmalexandersen]

Thanks a lot Pvannatto

Can you share your settings for Channel and Main Volume for your operation ?

Kind regards Nils

[pvannatto]

Hi Nils,

Attached is a copy of my church's default scene.

[nmalexandersen]

Hello again Paul ..

I have been thinking a bit, and I want to check with you if my theory holds water
Its regarding trying to find a ballpoint unity setting for the volum, master and output pots

We start of by sending two identical signals into two channels on the P16-M
Both have exactly the same level .. (I will be using -18 dBFS or 0 dBU)

Now .... we know that two identical signals will boost the combined signal with 6 dB if combined.

First you set the first channel on the P16-M to something .... lets say about noon (5)
Then you add the second channel, by rasing the volum knob ...

On the output of the P16-M you now have a PPM meter connected
You then raise the volum of the second channel to the point where the PPM meter reads an additional 6 dB of gain compared to the first channel alone

This (in my brain) will be the Unity setting for the channel knob
We can then assume that this also is the setting for the Master, as the structure is identical.


So far so good, but the Output Level knob remains ...
We just have to figure out the readout of the PPM meter, when we send a single -18dBFS signal through the P16-M using the settings described above.
Then raise the Output lever knob until the PPM meter reads the agreed setting
I kona it will not be absolute settings, but close enough

Do you agree ?

Kind regards Nils

[pvannatto]

To be honest Nils (@nmalexandersen ), I really don't see the point of this whole exercise, due to the fact that the P16M does not have any meters or readouts and the encoder LED dots are basically relative. The final outputs will sound different (at different volume levels) for different IEMs, headphones and wedges and will change due to stage noise level changes and ear fatigue. The P16M is designed as a simple mixing console so that the performer can mix the input signals to the point where it sounds right in his/her IEM, headphones or wedge, irrespective of where theoretical unity gain is.

[nmalexandersen]

Thanks for your reply.

What I am after is to make sure (or as sure as I can be) that if I have i.e.18 dB of headroom on mu X32 .... the P16 system has the same.
That way ... I can feed the output of the P16 into sennheiser IEM transmitters, and be sure that these also has the same headroom to work with.

Nils

[GaryH]

@nmalexandersen P16M volume adjusting. There are 3 control levels and a limiter.

1. VOLUME knob (right hand side just above ch 15 and 16) adjusts the level for EACH selected mono, stereo-linked channels, groups, (for each of the 16 ch buttons along the bottom) This same knob also controls the MAIN stereo bus signal. (See MAIN below) So this volume knob has TWO different independent volume control functions-this is very often overlooked!

2. MAIN button selects the main stereo bus signal, which has its own settings for volume, balance, and equalization. Apart from those of the 16 lower ch’s.

3. OUTPUT LEVEL knob at the top right controls the overall master output level.

OUTPUT LIMITER
This knob controls the limiter threshold for the master output.

All of the above can vary the output to your in ear system and are different for each p16m user. It’s the whole idea of a personal monitor. The point is you can’t have one static safe out level as each one will be set (slightly) differently depending on the user. The best bet might be to try and adjust the limiter similarly on each p16 to compensate for potential higher than expected output. It still becomes somewhat of a guess as there is no detent or indication of a numbered setting for it.

[nmalexandersen]

Hi Gary, and thanks for your reply.

I am very aware of the Gain staging points inside the P16-M, and also the fact that there are no markings on the volum pots (especially the Output)
So I am only interested in ballpark settings .... that are sort of repeatable by marking them with a sticker of some sort ..

What I don´t want to happen is to distort the P16-M internally. What surprised me a bit talking to Behringer support is that they could not give me information about the level pots. I asked if they were only attenuators, or of there was Gain available for the Pots ... but they could not or would not answer.

Cheers !!

[GaryH]

@nmalexandersen I do think you would be able to ballpark a knob setting with some sort of marker or something but on what knob from which position...really the point of my post before detailing the 4 areas that effect the final output (sorry for any info you were already aware of) There are several possible ways to alter the output and nothing to prevent a user from moving any of them mid show/event, on purpose or by accident. So you mark the top right output level knob but someone then taps the main button and turns up the volume knob there, a different knob. Maybe marking the limiter threshold position would offer a safety margin, but of all the controls, that one seems to be the most arbitrary of them all with regard to replicating knob position once it's moved.