Saturday, April 30, 2005

Call for better AM leadership

AM radio is the oldest form of radio. Despite repeated attempts to modernize it, including wideband transmission, various AM Stereo schemes, AMAX and others, we are left with a less than stellar AM listening experience overall. After listening to the harmful effect Portland Oregon's first AM HD IBOC digital broadcast has on existing AM radios, I wonder just how many more AM listeners we are going to lose before we figure out what it takes to get the most out of AM radio.

I think the core problem is the unaddressed need for leadership. The FCC badly mangled AM Stereo and looks to be making a bigger mess of things by allowing AM IBOC onto the air, but only during the daytime hours. (IBOC sideband noise is too high at night.) Ibiquity is in a position to help the AM band see more of it's potential through it's licensing of HD technology to radio receiver manufacturers.

We have understood how to make good quality AM radio broadcasts for many years, yet here we are in the 21st century still listening to poor quality narrow bandwidth audio being broadcast by an increasing number of stations. Despite what AM fans say, AM is not ever going to deliver the quality of service that newer technologies, such as FM and Satellite radio do, yet we are not seeing all that AM radio is capable of. Why is this?

I have come to believe it is because we are not taking the fickle nature of AM radio into account as we try to improve it and that's largely a leadership problem, not a technology problem. You see, AM radio is about tradeoffs. Everything is a give and take that demands a careful balance be maintained; otherwise we all fail to realize the full potential AM has to offer.

I'm not a fan of AM IBOC technology, largely because the quality of the digital audio is not good enough to warrant the harsh tradeoffs required for it's broadcast. AM IBOC stations must be narrowband analog to make room for the digital signals. That means harsh 5Khz, or less, brick wall analog filters that introduce ringing and distortion audible on even marginal AM radios. The digital signal itself adds noise to an already noisy medium, for those listening on ordinary AM radios. Given the just huge number of existing radios, it does not seem right to just slowly render them useless in favor of a marginal digital solution.

So what to do?

We need to coordinate the use of the AM band, keeping the interested listener in mind. It is these listeners, and more importantly potential new ones, that keep radio viable.

Interesingly, Ibiquity licenses it's digital HD radio technology. It is not possible to make an HD radio without first licensing the Ibiquity core technology and that licensing comes with terms. Normally, I am against this kind of thing, but perhaps it makes some sense where AM radio is concerned and that's the core reason for this post really. Maybe we can use Ibiquitys unique position to force the right kinds of AM improvements.

Look at the difference between the HAM radio spectrum and how it's used and the CB spectrum. The HAM radio operators work hard to get the most of their spectrum. They work together to innovate while not diminishing gains already made. The CB spectrum, on the other hand, is simply a mess with nobody doing much of anything besides shouting as loudly as they can in the hopes of being heard over the noise. The resulting experience is striking in that CB radio, though capable of long distance communication with clear and pleasant audio, is reduced to the worst of both. Narrow, distorted audio and local communications are the norm. Everybody lost with CB.

I do realize the issues surrounding CB radio are more complex. Just think about the leadership issue and it's potential advantages and let the rest go for the purposes of this post.

It's a given that no one AM modulation technology solves all the problems. This means that we really should not dismiss any one technology, out of hand, in favor of the others because we would not be gaining anything. The ideal approach is a well applied mix of existing technology that allows broadcasters to tune their programming and signal in a way that best serves their listeners.

The problem with this is that receiver manufacturers don't see a clear standard to build to so they end up building to the lowest common denominator. We learned this from the AM Stereo struggle where we did not endorse one technology, but let them compete to our mutual demise. AM Stereo is in wide use in many parts of the world that chose to learn from our mistake and support one technology solution.

If Ibiquity would include analog support specifications in their license terms, we would then have some leverage on how radios are made which would bring the combination of choices to the table necessary for AM radio to improve as it should be doing. There would be then two kinds of radios:

Ordinary analog radios, just as we have them today. These would continue to be a mixed bag with the receiver manufacturer free to do what they will.

Digital HD radios would support both AM and FM HD IBOC broadcasts and also support the analog AM options that make sense as well, namely: AM Stereo, AM mono and a narrow / wide option that could easily be incorporated into the treble control so users don't have to deal with another control. Impluse noise blanking would be a nice addition here as well.

All of that could fit onto one chip. I'll bet such a chip already exists and could be put to the task right away, making this a whole lot easier.

The core idea behind this to be a solid platform for AM radio that is a known and stable quantity. This stability would then promote better quality AM broadcasts. Ibiquity could make this happen largely on their own to all our mutual benefit.

It would be nice to also begin work on a more realistic AM band plan. Over time, as stations upgrade their facilities, channel allocations and broadcast types (AM Stereo, AM narrowband, AM IBOC Hybrid, AM IBOC only) could be mixed and matched to the mutual benefit of everyone.

This alone would make the purchase of new HD radios justified, regardless of your position on AM IBOC because AM analog would improve as well. Since IBOC is not a cure all, an improved analog scene just makes AM that much better to listen to as a whole.

AM Stations could then choose to broadcast full time analog AM Stereo broadcasts and be assured of new listeners. AM HD stations could use AM Stereo to cover their night time broadcasts, or simply choose to broadcast wideband AM or whatever else they think might best serve their listeners.

That's it really. I'm not a fan of HD IBOC on AM because it ignores all the progress and quality gear we have today. However, I'm also totally aware of the analog issues too. There is no one stop solution that will fix AM radio. What we all really want is better AM radio, why not apply the full range of avaliable solutions to the problem and just make AM better?


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