KVR Audio

Left Headphone · Post by **Left Headphone** » Fri Jul 01, 2005 10:34 pm

SPAN has a RMS L 00/00
RMS R 00/00

What is the 00/00? Are both of these peak meters? I'm getting like -15/-12, but I don't know what they mean?

kritikon · Post by **kritikon** » Sat Jul 02, 2005 2:15 am

From memory, Span has a continuous RMS readout and a peak RMS readout. The one that changes alot will be the continuous RMS and the one that remains more or less the same will be the peak RMS.

RMS = Root Mean Square. It's just a way of getting the average volume rather than the peak volume. When I say the peak RMS, I mean the maximum RMS present in the song.

Left Headphone · Post by **Left Headphone** » Sat Jul 02, 2005 2:19 am

Thanks for clearing that up...

kylen · Post by **kylen** » Sat Jul 02, 2005 4:02 am

kritikon - I think you're remembering RMS Buddy...SPAN has RMS and K-Scale (see Bob Katz) where there is a -3dB difference for loudness mastering purposes...

Aleksey Vaneev · Post by **Aleksey Vaneev** » Sat Jul 02, 2005 6:32 am

Indeed, they are same RMS values, but other having 3 dB added.

JonnySun 2.0 · Post by **JonnySun 2.0** » Sat Jul 02, 2005 3:13 pm

Hi Aleksey, is it possible to make a help-file for SPAN? There are many meters and much to explain ..

I use it intuitively but there are questions, though .. Like "Why there are options to choose the slope". Because i can't see the sense in choosing other db-value as "0 dB".

Aleksey Vaneev · Post by **Aleksey Vaneev** » Sat Jul 02, 2005 5:22 pm

It's not a commercial plug-in and thus I'm not sure this kind of detail in necessary. You may lookup user manual for GlissEQ or Soniformer for details about slope control. 0dB slope is pretty inconvenient as even classic analog analyzers had +3 dB/oct slope. +4.5dB seems like a good choice in average - it leaves most modern musicpieces draw a relatively 'flat' spectrum on the spectrum analyzer (except that they usually have drop-offs before 100 Hz and after 10 kHz).

Without correct slope setting you'll always have to draw a correct slope in your mind yourself. Without such correction it can be relatively hard to get a good spectral balance.

Dazza66 · Post by **Dazza66** » Sun Jul 03, 2005 12:47 am

JonnySun 2.0 wrote:Hi Aleksey, is it possible to make a help-file for SPAN? There are many meters and much to explain ..

I use it intuitively but there are questions, though .. Like "Why there are options to choose the slope". Because i can't see the sense in choosing other db-value as "0 dB".

There is a small 'help file' im the readme file that comes in the SPAN download, and it mentions slope. Here it is:

"SPAN is a real-time FFT spectrum analyzer PC VST plug-in. For the most part it
was derived from GlissEQ and CurveEQ professional equalizers and it reproduces
their spectrum analysis functionality.

Parameters:

Block - specifies the block size of the FFT (Fast Fourier Transform)
spectrum analyzer. The more the block size the more the resolution
in the lower frequency range, but less time coherence in the
higher frequency end.

Speed - specifies the speed (averaging coefficient) of the spectrum
analyzer. The less the speed the more latent spectrum analyzer is.
This setting is effective only if the "RealT" monitoring mode is
used.

Slope - allows you to adjust the spectrum analyzer display slope towards
higher frequencies. This can be useful because higher frequencies
are usually weaker than lower frequencies, and thus tuning them
can be a difficult task. By choosing an appropriate slope setting,
you can compensate for this behavior and make the spectrum plot

more convenient and meaningful.

Channel - specifies which audio channel gets analyzed. "Avg" means the
average of the L and R channels will be analyzed. "Max" means
the maximum of the L and R channels will be analyzed.

Monitor - specifies the monitoring mode. "RealT" means real-time
spectrum is displayed. "Avg" means "average of all time" is
displayed. "Max" means "maximum of all time" is displayed.

In the "Inertia" mode the previously displayed spectrum will
be displayed again in a darker color.

In the "Full" display mode the whole spectrum resolution is
used. Other options offer graph displays of varying resolution.

Low Freq/High Freq - frequency range to display.

dB Scale - specifies dB range to display. First value is dB shift and
the second value is dB range.

Peak Hold - amount of seconds to keep peaks displayed.

You can click the analyzer surface with the left mouse button to reset
the analyzer.

Click any of the statistics counters to reset all counters. Please note
that RMS counters show dB values: A/B, where B = A + 3 dB. PRMS (peak RMS)
counter has 50 ms averaging time."

BTW, I think this is such a fantastic plugin for understanding whats going on in your mix - I've tried a few others, but this is the best by far (well, for the free stuff anyway)

greendoor · Post by **greendoor** » Wed Jul 06, 2005 12:57 am

OK - now i'm as confused as hell. The K System has three options - 20,-14 and -12. I don't get this 3dB thing. Also - is it a linear 3dB taken off the RMS, or is it a slope of 3dB? Very, very confusing - which means I can no longer trust Span or any Voxengo product. Is there any other known-good analysers that give true RMS that I can test Span against?

No complaints about the sound quality - I don't normally look at the numbers, but I would like to start using them more.

Left Headphone · Post by **Left Headphone** » Wed Jul 06, 2005 1:23 am

greendoor wrote:OK - now i'm as confused as hell. The K System has three options - 12,-14 and -12. I don't get this 3dB thing. Also - is it a linear 3dB taken off the RMS, or is it a slope of 3dB? Very, very confusing - which means I can no longer trust Span or any Voxengo product. Is there any other known-good analysers that give true RMS that I can test Span against?

Me too!!!

Aleksey Vaneev · Post by **Aleksey Vaneev** » Wed Jul 06, 2005 6:57 am

greendoor, 'no longer trust any Voxengo product' - quick conclusion, eh?

RMS dB values: A/B
A is UNADJUSTED (actual, unweighted RMS value). B is A + 3 dB: also unweighted RMS value, just a plain A RMS + 3dB value.

3 dB is added to unadjusted RMS/PeakRMS value to convert this value to Katz System RMS/PeakRMS value. Katz metering system is not a system for hardware - it is a system for mastering engineer. YOU should monitor Katz RMS/PeakRMS values and decide whether they fit -20, -14 or -12 system or not.

greendoor · Post by **greendoor** » Wed Jul 06, 2005 9:39 am

Sorry - I have no idea what you mean. All the stuff I read about metering mentions Peaks and RMS - which I think I understand. I think I understand the Katz system as an agreed "headroom" for the digital world. But I have no idea why you are adding or subtracting 3dB. Sorry - totally lost me. I see people asking similar questions about Elephant and other Voxengo products. I don't think anyone understands your answers either.

.jon · Post by **.jon** » Wed Jul 06, 2005 10:07 am

I think most do understand, greendoor.

greendoor · Post by **greendoor** » Wed Jul 06, 2005 10:33 am

Well if you understand, please explain. I didn't start this post - so i'm not the only one who doesn't understand. I think most people here don't even understand the question ...

greendoor · Post by **greendoor** » Wed Jul 06, 2005 10:37 am

And unless there are some alias names being used, other people are asking the same question about Span in other forums. What's so special about adding 3dB to RMS? I've read about Katz and can't see any reference to it, other than Voxengo speak.