Broken VU output amplitude after update

Do you understand the profound impact of the DRC here...?
everything is distorted...
;-)
No. Sorry. I have a hard time with understanding what you write.

I know what DRC is but cannot see the relevance for measuring the dBFS.
 
No. Sorry. I have a hard time with understanding what you write.

I know what DRC is but cannot see the relevance for measuring the dBFS.
Look for the discussions from a few months ago about this DRC... which were swept under the rug but which render your rigorous considerations regarding the VU meter obsolete... and which actually had a heavy impact in many sensitive subjects here .. never addressed... a very clumsy Wiim workaround...
 
Do you understand the profound impact of the DRC "anti-saturation digital" here...?
everything is distorted...
;-)




Even though I understand your justified request for many months...
;-)
You still want to know the peak level regardless of DRC. What profound impact are you talking about?
 
Look for the discussions from a few months ago about this DRC... which were swept under the rug but which render your rigorous considerations regarding the VU meter obsolete... and which actually had a heavy impact in many sensitive subjects here .. never addressed... a very clumsy Wiim workaround...
Are you talking about the limiting that WiiM use to prevent clipping? Yes I can see that would complicate things.
 
Before, of course.
Do the compression even happen on the digital outputs? Or only before the DAC?
I'll let you investigate... ;-)
But realizing the impact on the rest of the circumstances used on different Wiim systems (not only ultra -vumetre) remains quite essential, it seems to me...
;-)
 
I'll let you investigate... ;-)
But realizing the impact on the rest of the circumstances used on different Wiim systems (not only ultra -vumetre) remains quite essential, it seems to me...
;-)
So you think WiiM is using DRC in other cases than to avoid clipping in the DAC after applying gain in the EQ settings?

We need to have that confirmed by the @WiiM Team .
 
No. Sorry. I have a hard time with understanding what you write.

I know what DRC is but cannot see the relevance for measuring the dBFS.
It is documented here
 
It is documented here
If the WiiM algoritme always reduce any applied gain then we don't need a clipping indicator but it would still be good to have an real indication of how close the signal level is to 0 dBFS.

On input it will show the dynamic range of the source and on output we could see if this "advanced algorithm" is about to getting applied.
 
I just did a few VU-meter tests myself:
  1. VU meter "Original Signal" setting
    • With -14dBFS RMS / -11dBFS peak 1kHz sine the VU meter shows about -11dB
    • With -14dBFS RMS / -8.5dBFS peak pink noise the VU meter shows about -6dB
    • With either input signal VU meter level doesn't change when I enable EQ or RoomFit with +6dB boost at 1kHz, nor when I added +7dB of pre-gain boost to the input, or changed output level.
  2. VU meter "Output Amplitude" setting
    • Pink noise and 1kHz tone with the same -14dBFS RMS level result in different VU meter readings (i.e. like above).
    • VU meter level is affected by input pre-gain, output level, EQ and RoomFit.
My conclusion based on above results is that the current implementation of VU meter doesn't match signal peak nor signal RMS levels.

Regarding DRC, IMHO @canard is implying that the story is more complicated than it really is.
According to my tests, WiiM only apply DRC/limiting when the output of the device would be pushed over 0dBFS in digital domain, to avoid hard clipping.

DRC seems to be triggered only when output volume is at (or close to) 100%, combined with some kind of digital boost (either pre-gain, EQ or RoomFit) and when playing back content with peaks close to 0dBFS. I.e. even with boosts in the flow DRC won't be triggered if volume isn't high enough to end up above 0dBFS at DA conversion (or digital output).

For sure DRC/limiting is much more gentle to the ear compared to digital clipping, so I personally find this limiter to be a smart safeguard, useful for casual users who might not know how to achieve optimal gain staging.
 
Back
Top