final loudness.. ebumeter and k-meter

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calimerox
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When i m mixing stuff i m just running into a loudness problem. maybe you can help me out:

Usually when mixing music i use the k-meter of mixbus to get a visualisation of the loudness and dynamic range of my mix. when i do broadcast stuff theres the ebumeter and there are in europe some standards of loudnes: the „target level“ should be -23LUFS +/- 1.

But when I m mixing with correct levels due to the ebumeter and take a look at mixbus' k-.meter, the k-meter does hardly move, my mix is much lower in volume, and the master peak level is around -12db.... so i cant really use the kmeter...

maybe i m mixing up two different things right now.. I really like mixing with the k-meter, so it would be helpful for me to adjust somehow the two meters, although of course they re based on different algorithms/approaches to measure volume / dynamics... how do you handle that?

calimerox
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I havent tried with the external k-meter yet.. maybe I should ask the harrison guys directly..

seablade
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Not having used the ebumeter there isn't a whole lot I could help you out there with I don't think. It would be worth it to jump on IRC sometime during the daytime EST and see if you can get an answer there, or drop them an email certainly. Keep in mind we are approaching Christmas so people's schedules will be a bit more hectic than normal, no idea when the Harrison folks will take off for the season from IRC for example.

Seablade

Edward Diehl
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Possibly its useful to compare Mixbus with 2 other kmeter's which available for linux:
kmeter: http://code.mzuther.de/kmeter/
jkmeter: http://kokkinizita.linuxaudio.org/linuxaudio/downloads/index.html

Also the jmeters at kokkinizita has several different kinds of meters based on different loudness systems.

the C.L.A.
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AFAIK usually the k-meter uses a straight RMS meter with a given reference level. In case of the k-14 meter (as used in Mixbus) this is at -14 dBFS. There are also k-20 and k-12 meters to serve different use cases.

You could say the ebumeter uses an even lower reference level, but it also applies some filtering and additional rules (for example for handling surround channels if used) to match the perceived loudness more closely than a RMS meter does. This is also why they use the terms LU (Loudness Units) and LUFS instead of dB and dBFS.

Hence you can't really match the ebumeter with a k-meter, wich makes it more a decision wich metering standard meets your needs best in a given situation.

So if you decide to mix to the EBU R-128 standard you might possibly want to ignore the k-14 meter in Mixbus altogether. I hope that Harrison will make their loudness meter switchable to different standards in the future.

If you want to know the differences between the meters more precisely than you might want to read up here:
http://tech.ebu.ch/loudness
http://www.digido.com/how-to-make-better-recordings-part-2.html

P.S.: At the end of the second link there is also mention of a K/ITU meter wich I guess will use the same filtering as the ebumeter. Mixbus currently uses the standard K/RMS meter, though, AFAIK.

P.P.S.: Obvieously the meter in Edward Diehl's first link is switchable between RMS and ITU metering. Got to try it and compare... :)

ccaudle
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I think the short answer is you are expecting meters to do something that they were not intended to be able to do.
I would start by reading Bob Katz's original metering and level articles which explain the concepts, and explain the reasoning behind his K-meter recommendation:

http://www.digido.com/articles-and-demos12/13-bob-katz/22-level-practices-part-1.html
http://www.digido.com/how-to-make-better-recordings-part-2.html

It sounds to me l like you are comparing an EBU meter which is roughly equivalent to a K-20 meter, to a K-12 or K-14 meter.

Remember meters are a guide or signpost, what you really should pay attention to is the section in the articles on properly calibrating monitor level and picking a monitor gain appropriate for what you are trying to mix (e.g. reference level for film style levels, which I think is what a target level of -23 LUFS would be aiming for, or 6dB below reference for dynamic pop, or 10dB below reference for really squashed highly compressed pop, etc.). Mix by ear and just use the (appropriate) meters to verify you are in the range you wanted to be.

Regarding your original question, see if there is an option to change the K-meter to a K-20 style meter, it should more closely match the EBU meter.

calimerox
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thanks for all your answers, Harrison also got back to me and i told them it would be useful to have a switch to "ebu-mode" for broadcast etc..

@ccaudle thanks for your answer, I m aware of how a kmeter works etc, my simple problem is: if i have to mix to a -23LUFS standard, I m getting the level so low, that i cant really see anything on the k-meter / use the master channel strips lookahead limiter etc. because i m on such a low level..
so i got two choices: mixing with kmeter and then leveling everything down at the end, or leveling directly in ebu-mode, and cant really use the master channels tools.

for the first choice i feel i ll lose some bit depth and dynamics by doing that (maybe i m wrong with that)...

@Edward Diehl thats a good suggestion , I ll check that out and compare the meters guess that will be in 2013...

@the C.L.A. yeah more reading is good, cause i m quite new to this issues.. thanks

the C.L.A.
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@ccaudle: As noted in my previous post you can't match the EBU R-128 meter to a standard k-meter with RMS measurement because of the additional filters that are being applied to the EBU R-128 meter. It's very obvious when you sweep a sine wave across these meters: On the K/RMS meter the displayed level is the same across the whole frequency spectrum. On the EBU R-128 meter or the K/ITU meter the displayed loudness level varies with frequency.

@calimerox: The lookahead limiter in Mixbus AFAIK is only intended as kind of a security measure so you don't get any digital (and intersample) overs. So it's just fine if you don't hit this limiter. I guess only the threshold range of the regular master channel dynamics is a bit low for mixing towards the EBU R-128 standard. I think I would try to mix toward that level nonetheless and maybe use a compressor plugin instead. Or maybe use a post-fader gain plugin to reduce the level after the dynamics section of the master - could be worth a try at least (edit: You could also just turn down the master fader a little instead of using a gain plugin, if you don't want to leave it in it's sweet spot for a manual fade out or master channel automation). In both cases the builtin k-14 meter would be useless and could be ignored completely.

calimerox
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@ the C.L.A.
thanks for making that clear. Maybe a post fader gain plugin would be the easiest way to go in my case. I m still not sure how to proceed in general: I feel very comfortable with mixing with the k-meter, although it seems the ebu standard will push through at least in the broadcast world. For music production it seems to be a little low level.. Best way to go for me would be just concentrating on one way to measure loudness, where it doesnt matter if i mix music or broadcast.. but not sure if that ll be possible?

Koivukoski1
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Sample rate issue?

The ITU document specifies the K-filter as
two biquad sections and provides coefficients
only for a sample rate of 48 kHz, adding that
implementations supporting other rates should
use ’coefficients that provide the same frequency
response’.

-Koivukoski1