First off, a statement: I have no problem with the principle of mixing
to a constant loudness, because it's how I was trained at Evesham 30 years ago
and it's how I've mixed shows for 20 years. The idea is not new, but in recent
years due to lack of training it's fallen out of practice and people have
become slaves to the PPM without using their ears,
Second statement: I do not consider myself to be the greatest mixer in
the world. I could be wrong about all this. But I DO mix 10+ hours of network
TV every week, and I have lots of chances to measure and experiment. There are
some major problems I have found, and nobody has yet been able to answer them;
there are many "Heads of Technology" who are quoting me chapter and
verse on R128, but few craft mixers who have actually done it.
I'll start on the small bits and then work up.
Firstly, why are we doing this? I thought the biggest complaints from
viewers were about adverts and promos, yet these are not covered by R128! There
WILL be a spec for them, but why are we going to all this trouble when all we
needed to do was tame the commercials. Incidentally, the last year has seen a
reduction in advert level to the point where there doesn’t appear to be a major
discrepancy any more.
Secondly, the measuring algorithm. This whole thing is based around a
metering system which is meant to tell you how loud something sounds, rather
than how much it meters. Hang on, didn't we already have something that could
do that? Like a pair of EARS? Wouldn't it have been a lot simpler to just train
people to use the PPM and LISTEN, like I was taught? Then we could have kept
the system people were familiar with. I even had an acronym for this.
P.E.T.: PPM. Ears. Training.
But if you're going to replace humans with machines, then you will have
made sure that your ear-measuring meter actually matches what a human ear
hears? When we moved to our new home at MediaCity our studio gained a loudness
meter, and I started measuring everything we did. I found that between shows,
with a fixed monitor gain, speech which sounded constant to me was reading
DIFFERENTLY on the loudness meter. Even within a run of the same show, there
were inconsistencies. It seems that the faster the speech, the more it
"fills up" the integration, even though it doesn't sound louder to
the ear. I've seen errors of up to 2 LUs between shows; this is as much as the
variance allowed on the DPP spec!
Now I'm aware that my opinion alone may be incorrect, so I've asked a
few people, both sound and non-sound staff, what they thought, taking care to
word the question in a way that doesn't influence them. They seem to agree with
me. This is, of course, not a scientific study, but it does seem to confirm
what I think I'm hearing.
Maybe hearing is such a subjective thing that any algorithm to measure
it should take into account a lot more than just the "area under the
curve" of an integrator?
Thirdly, the selection of the "Integrated" value as the
criterion for program acceptance. The idea that the viewer cares about the
overall level of a program is, I think, flawed. What the listener cares about
is having to turn their TV up or down, and the thing that causes this is
dialogue variation, whether the wrong level or with too much dynamic range. The
EBU say that this allows for greater dynamics within a show, but with no
restrictions on short-term level variation it is possible to mix a program that
has so much dynamic range it's unlistenable even though it hits the numbers.
This was, of course, possible with the old system, but I thought the new one
was meant to sort this out? I've taken show segments, made them unlistenable
with massive level variance, and then submitted them for testing to QC. All of
them passed! How can this possibly benefit the home viewer? Again, if the new
system is no better, why not stick with the old one and train people to use it
properly?
Fourthly and finally....
Following on from the above, there is a major problem with only
specifying integrated as a delivery requirement. This is a major practical issue
for me, and so far I have conflicting replies from anyone I've asked. Bear with
me, this may take a while to explain.
First, a question, the answer of which is very important:
"Across a network, should the average loudness of normal presenter
speech be constant between shows, and is so what should it be?"
The official answer I had from the DPP is "Yes, -23LUFS", as
is that of Hugh Robjohns in this month's Sound On Sound article on loudness.
There is NO information on this in the delivery requirements.
To understand the problem, we must follow through the implications of a
Yes or No answer to the above. We must also look at the basic components of a
TV show mix, and how they interact.
A TV studio sound mix typically has three components: Speech, Music and
Applause/FX. These are balanced to sound correct relative to each other, and
the idea is to maintain an appropriate dynamic range for the home
listener.
The problem is very simple. For some shows, the speech is the loudest
part of the show, for others the quietest, and for some it's in the
middle.
Examples:
Speech is loudest: Newsnight
Speech is in the middle: Countdown
Speech is quietest: Jeremy Kyle
.
I know these are on different networks, but the principle is valid
regardless.
So,consider the YES case:
We wish speech to be constant between shows. The DPP recommend -23 LUFS,
so that is what we do.


RESULT FOR THE "YES" CASE: The viewer is happy, the mix sounds right but we cannot conform
to the integrated DPP spec for R128.
Now consider the NO case:
This is easier from our point of view. If we don't have to match speech
levels, then we can keep our mixes the same, and simply offset the level to hit
the DPP spec.
RESULT FOR THE "NO" CASE: The DPP spec has been satisfied, the mix sounds right but the viewer
is still left with inconsistent dialogue levels and STILL has to turn their TV
up or down between shows. Nothing has been gained.
There is a third case: We remove all dynamics from our audience shows so
everything is at -23LUFS.
RESULT FOR THE THIRD CASE: The DPP spec has been satisfied, the viewer has constant loudness, but
the whole experience of the show is lost, and everything sounds like Radio 1.
As a craft mixer, I don't consider this an acceptable solution.
Although the DPP recommend the "Yes" case, in practice the
"No" case is what is happening. Mixers can set their speech as they
wish to allow higher or lower levels, and it all seems fine if you consider a
show in isolation and NOT as part of a greater network. We end up with what we
had before: inconsistent levels between shows which defeats the entire object
of R128.
All of this results from the decision to use the "Integrated"
value only, which as you see causes major problems. It's interesting that our
European cousins have all picked different things to measure from the original
EBU spec. The American networks seem to have realised the problems, and often
have rules for dialogue levels as well as the overall show level.
This last question in particular is the one that I have never had
properly answered, Every time I raise this, I get chapter and verse of
R128 quoted at me, but the questions are never answered and eventually everyone
goes quiet.
I am NOT trying to be awkward; I believe these are genuine concerns, and
I want them to be answered in a satisfactory manner. The new spec is only
acceptable if it works for ALL genres, and it clearly does not.
I believe we are throwning out a standard which had flaws but worked
fairly well for 80 years, and we are replacing it with one that won't even
solve the problems it was meant to.
Why did nobody ask the people at the sharp end?
Excellent post Jake!
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