PPM Radio Rating Blind Spot

I'm always interested in the PPM rating results for our local radio stations. Often, when I learn the numbers, I'll even write about it. I just assumed PPM (Portable People Meter) dependably measured stations encountered, but apparently it has "blind spots".

This article was enlightening for this radio fan. Depending on the station's encoding, the PPM may or may not pick it up. In fact, if the station is primarily talk, it's often missed.

Voltair is a new service marketed to radio stations that promises "advanced audio signal processing to enhance the detectability of the watermark codes within the context of your programming objectives." In other words, it eliminates the blind spot so the PPM gives full credit.

In a couple of tests by Harker Research, ratings increased up to 61% when Voltair was installed. Nothing else was changed, and ratings spiked.

The most important lesson here is that the rumors about Voltair helping improve ratings are true. This is the clearest evidence that PPM as implemented is flawed.

PPM does not capture all listening, so it under-estimates radio listening–potentially by a lot for some formats.

The solution is for Nielsen to admit that the problem exists and agree to a time-table to fix it.

It is likely that PPM will never be perfect. It will never capture all listening, but missing 20%, 50%, or more should be unacceptable.

Remember, we don't know which stations are using Voltair and which are not. That makes an already imperfect system even more suspect. There has to be a better way to measure radio listeners.

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Every rating system has major flaws. The diary system is flawed, PPM is flawed and I'm sure flaws will surface for this new and improved system. Good radio managers know not to panic about one or two under-performing books. You have to look at how a station trends over a number of books. Doing so usually smooths out the shortcomings of the rating system being used. If a station is actually serving its demographic properly, the share points will come.

June 2, 2015 @ 10:48 AM

Toronto Mike Verified as the defacto Toronto Mike


Ok, but let's say two stations target the same demo. For fun, let's say 590 and 1050.

Let's pretend 590 has installed Voltair and 1050 has not. Let's say this means 1050 is not getting credit for 50% of listening time in their targeted demo.

IMHO, this doesn't smooth itself out over a few books so long as their encoding isn't identical.

June 2, 2015 @ 10:55 AM


Well, first of all I believe all stations would in a marketplace would have to agree to the same ratings system before implementing it. It all boils down to impressing potential and existing advertising dollars. If one station is using one method of ratings gathering that no one else is using... both systems become worthless - especially if the results are inconsistent. Who's telling the truth?

June 2, 2015 @ 12:25 PM

Toronto Mike Verified as the defacto Toronto Mike


The stations have agreed to PPM, but I believe this encoding booster is fairly new and stations using it are hesitant to admit they use it.

Remember, it doesn't cheat the system, it merely eliminates the aforementioned blind spot.

June 2, 2015 @ 1:23 PM


I get that but the bottom line for stations is, you can't sell anecdotal numbers to clients. If The Fan 590 has the booster and 1050 doesn't, it doesn't matter. Rather than buy the booster, TSN reps could just tell their clients that if they had the technology their ratings would be 60% higher too. As I said before, all the stations in the market have to play the same game in order for the rating system to mean something.

June 2, 2015 @ 4:31 PM

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