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TV Levels at Home: A Canadian View

History buffs and reasonably alert readers may recall that back in the day (2003-04), I wrote several articles dealing with the disarray of audio levels at our beloved end-users' sofas, couches and recliners.

Among other things, I noted that (a) we experience a variance of something like 18 dB in levels across channels, (b) that dialnorm is usually left in the default setting, or else switched to its "no attenuation" level (both constitute an abuse of the dialnorm concept), (c) that digital tiers are usually significantly lower in level than analog tiers and (d) in general, it's a miserable state of affairs regarding audio levels in televisionland.

Well, here we are in 2006. How're we doing? Well, not so hot, it appears. But, there's hope! First, let me share with you some other poor benighted soul's misadventures with TV audio. Avanti, as we used to say in South Bend!

AUDIO UP NORTH

For those of you who don't know of Neil Muncy, well, you should. Neil is an audio guru's audio guru. I got to know him back in the 1980s when he was teaching and inspiring people at the now legendary NPR Music Recording Workshops. He instantly became a mentor for me, and has been a source of inspiration and information ever since. Back in the 1960s, he built custom consoles (before there were console companies!) for a range of clients. Some of those consoles are probably still in service today. He has a number of really juicy engineering credits ("Bill Cosby-Himself" for instance) and in more recent years, he has been at the forefront of some significant acoustical innovations (with Peter d'Antonio of RPG and Dave Griesinger of Lexicon) as well as a movement to improve the quality of audio system grounding (with Bill Whitlock and others). In short, Neil is da man! No two ways about it.

Well, about a month ago, I got a call from Neil, who had spotted one of my columns on TV levels and wanted to share with me a little about his experiences in Canada, where he lives.

Neil's cable provider is Rogers Communications Inc., a major Canadian telecom company. Neil was fairly comfortable with his cable services, subject to the usual sort of professional gripes about picture quality and general limitations of TV audio (not Rogers' fault). However, in April 2005, Rogers "went digital" and things changed, for better and for worse.

On the plus side was a better picture and better basic audio (meaning improved bandwidth and dynamic range). At the time, Neil said, Rogers simply set dialnorm to -31 dBFS. Interestingly, Neil found the general array of levels to be sort of satisfactory at that point (which is not what I've found in the United States with Charter Communications).

The downside began to emerge, according to Neil, in October 2005, after an initiative was undertaken by the Canadian Cable Television Association to fully implement the dialnorm protocol as specified by Dolby. At that point, Neil said, levels began to diverge again, by as much as +/-10 dB. Not good.

Now Neil is not one to fly off the handle. He's a measuring fool (like me) and so he has begun to carefully measure both the electrical audio signal and the acoustical levels, using a variety of meters and protocols. He has also gotten in touch with both Dolby via Jeff Riedmiller, and Rogers' technical staff to help diagnose the problem.

The problem is that Neil cannot reconcile the measurements he makes with a VU meter, a peak meter, an A-weighted real-time spectrum analyzer, an A-weighted slow-detection sound level meter and what he hears. Neil has also, on occasion, used the Dolby LM100 meter as well, courtesy of Riedmiller.

As Neil puts it with more than a little frustration, "Two stations that have the same dialnorm settings and the same Leq(A) levels may be up to 10 dB different! I don't know what it is, but something is not set right."

This from an audio guru's audio guru. You have to take it seriously.

PLAYING CATCH-UP

The easy way out would be to blame Rogers, CCTA and/or Dolby in the usual blame flamefest, but Neil has no interest in any of that and neither do I. After perusing the CCTA Digital Audio Working Group Web site ( www.ccta.com/english/View.asp?t=&x=247&mp=1) and having a couple of follow-up conversations with Neil and Riedmiller, a more nuanced picture emerges.

The current situation is this: TV audio levels management in Canada via dialnorm is very much a work in progress. Happily, there's been a lot of work and a lot of progress. Rogers is hard at work but admittedly a little behind the curve. Some of the other MSOs are currently doing quite well in this regard and CCTA is maintaining an active and productive stewardship of its members' needs and service commitments.

One of the most interesting and fundamental items on the CCTA Digital Audio Working Group Web site is a presentation from Riedmiller that should be required reading for all of us trying to deal with metadata ( www.ccta.com/CMFiles/CCTA_2005_Dolby_JCR64OKA-322005-2926.pdf).

There also are some interesting comparisons to be made with how the Canadian broadcasting industry and the American broadcast industry are dealing with these problems. It's instructive at all levels. I will continue this with a much deeper look at Dolby's view of things and the efforts of CCTA next month.

Thanks for listening.