The European Broadcasting Union’s PLOUD group has published new guidelines in a major push to solve the contentious issue of loudness.

Following viewer complaints about the difference in audio levels between shows and adverts on TV, PLOUD is plumping for the R 128 recommendation, which the EBU sees as the key weapon in what it calls “the loudness war”.

R 128 specifies the permitted maximum level of audio signals and the all-important definition of loudness normalisation. This moves away from the long-established method of measuring the peak levels of an audio signal and instead quantifies “perceived loudness”.

R 128 also offers what the chairman of PLOUD, Florian Camerer, described as “additional goodies”, including a method of increasing the bandwidth of signals, a process known as gating.

Camerer, a senior sound engineer at Austrian public broadcaster ORF, said: “We haven’t won yet but the chances are good - they’ve never been better.”

The problem of loudness arises when a programme with a wide range of sound levels is followed by a commercial or promo that has been heavily compressed.

Both might register the same peak level, but the differing strengths of the content will make one sound louder than the other.

Despite metering manufacturers displaying products at IBC that are said to comply with R 128, there is still the feeling in some quarters that the EBU recommendations, particularly regarding true peak, might not make much impact.

“We’re asking whether true peak is important,” said Richard Kelley, director of sales and marketing at meter manufacturer DK Technologies. “The UK has gone with the ITU spec, so are facilities going to change?”

R 128 was published during IBC last week, together with technical documents covering loudness metering and loudness range.

Two further texts, with guidelines for production and implementation and describing distribution of programmes, are
still awaiting approval.

The EBU recommendations are based on the ITU’s BS 1770, the first major attempt to deal with loudness, which specifies the use of loudness meters, rather than peak meters, to ensure consistent sound levels between programmes and adverts.

The UK’s PSBs are all members of the EBU.

Pic: RTW TouchMonitor