RP22 - immersive audio design



'Standards ensure consistency of experience'
Poppy Crumb, Dolby

What is RP22?

The new Recommended Practice CEDIA/CTA-RP22 for Immersive Audio Design is an essential document for two main reasons:

1) It raises the bar for every home cinema design and installation.

2) It provides four independently verifiable performance levels, created according to ISO methodology and industry expert consensus.

Not just home cinema providers, but manufacturers, calibrators, and experts from the film production and studio worlds have helped create this paper.

A room designed to RP22 principles will almost certainly perform better than one which hasn't.

RP22 is a free-of-charge download for industry and non-industry alike - download it here.

CEDIA/CTA-RP22 hard copy

RP22 is 154 pages long with over 20 performance metrics

What's in it for me?

For home cinema buyers: a more consistent performance, regardless of the level you choose.

Right now home cinema installation often suffers from 'brand religion' over 'engineering' - where the installers act as if magical products can overcome the physical limits of the room or layout they've chosen.

'Ye cannae change the laws of physics, Jim'

Montgomery Scott, USS Enterprise

RP22 will also help you compare proposals from different providers, apples to apples.

We're always advised to get several quotes, but it's hard if one firm's 'great' is lower performance than another's 'entry level'.

RP22 helps you navigate the maze.

For industry pros: you will create better sounding rooms by embracing RP22. Ignoring the pitfalls means you fall victim to them.

Levels of Excellence

The old CEB-22 guidelines were a big step forward at the time - 10 years ago the main problem was that 'home cinemas' didn't have the dynamic range to reproduce a film soundtrack properly.

However, things ended up a bit sort of binary, where a system was considered  'reference' (a term that has lost all meaning through overuse and abuse), or they weren't, and other important quality metrics were overlooked. There's a huge difference between 'reference level' (Sound Pressure Level is straightforward to measure) and 'reference quality' (largely meaningless and subjective), and the two often got confused.

A great thing about RP22 is that we break systems up into four distinct performance levels, as follows:

  • Level 1 - Home Cinema

'The minimum level to convey artistic intent'

In a modest sized space this should be achievable with pretty affordable, mainstream equipment.

  • Level 2 - Private Cinema

'More accurately conveys artistic intent'

Tighter metrics, more channels, more immersive - moving towards higher performance.

I believe that the Cinemaworks showroom in 9.1.4 achieves Level 2, and the measurements so far support that. In 5.1.2, it's Level 1.

Cinemaworks' demo home cinema - I believe it's Level 2

RP22 had a strong influence on the Cinemaworks demo room design

  • Level 3 - Studio or top-level commercial cinema

'Meets or exceeds reference commercial cinema exhibition standards'

Level 3 broadly corresponds to the previous 'reference' but is much more tightly defined.

  • Level 4 - State of the art

'The maximum level of achievable performance across every parameter'

But be careful!

Even at this very early stage - RP22 was released in September 2023 - we've seen some 'plausible BS' from a very few dealers and makes.

Statements like:

'Ours are the only speakers that can do RP22'

or

'I don't have any calculations... but this room is at least Level 2'

are unhelpful!

Here are some pointers:

  • Does your provider have externally verified training and design credentials? (Or, does their outsourced designer?) Or is it all from the 'school of hard knocks'?

  • Were they involved in the authorship or peer review stages of the RP22 document?

  • Have they provided you with design calculations, and do those numbers bear any resemblance to the metrics set out in RP22?

CEDIA Certified Designer
Image

What's next?

RP22 sets the standard for immersive audio design.

The next recommended practice is RP23 for video, which is well underway.

Two more key standards are also in development:

  • RP1 'Performance Facts' sets out required data from manufacturers of audio and video equipment which allows us designers to really compare accurately between makes and pick the best option.

  • RP32 'Measurement and Verification' sets out the methodology to prove the room achieves a given performance target.

I'm a proud volunteer member of CEDIA standards and sit on the working groups - partly because I believe I contribute, but also to ensure 'early access' to the very best practices, which influence my design work.

For me, standards allow me to create better rooms for myself and my customers, using verifiable, repeatable engineering instead of 'brand love'.

If that sounds like something you could benefit from, let's talk.