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WTDY Cranking the PPM Tones?

I've noticed a metallic/grinding noise on 96.5 WTDY-FM lately, characteristic of Nielsen PPM tones. It's on the HD signal too, so I don't think it's just analog noise/static.

I notice it especially in more complex passages of songs. It is a bit different from HD radio compression artifacts, at least to my ears.

Has anyone else noticed this, and is it PPM or something else?

For reference: Nielsen PPM Example (YouTube)
 
WTDY is unlistenable. I haven’t noticed a metallic or grinding noise but their audio is absurdly over-modulated. Every Sunday morning I tune in to the acoustic sunrise because it’s a great show but unfortunately most weeks I have to turn it off within 5 minutes because of the unbearable distortion. I’ve tried turning the bass all the way down on the equalizer and the cones on the speakers still sound like they’re going to blow.
 
WTDY is unlistenable. I haven’t noticed a metallic or grinding noise but their audio is absurdly over-modulated. Every Sunday morning I tune in to the acoustic sunrise because it’s a great show but unfortunately most weeks I have to turn it off within 5 minutes because of the unbearable distortion. I’ve tried turning the bass all the way down on the equalizer and the cones on the speakers still sound like they’re going to blow.
Are you listening to the HD or the analog signal? Whatever they're doing, it seems to affect the HD signal too. And I agree, it sounds very bad.
 
The analog signal. My guess is they have the pot set too high on the board.
With today's processing equipment, it really does not matter where the "pot" is set. If it is too low, the AGC processing will pull it up. If it is too high or has excessive peaks, the compression and peak limiting will handle the excess.

Back 50 years ago, I was PD of WCMQ in Miami. The owner was so tired of the jocks "pot whipping" that he had the engineer build boards that had no level control. The mike was set hotter than the music channels, but otherwise the automatic gain gear took care of everything.
 
The analog signal. My guess is they have the pot set too high on the board.
With today's processing equipment, it really does not matter where the "pot" is set. If it is too low, the AGC processing will pull it up. If it is too high or has excessive peaks, the compression and peak limiting will handle the excess.

Back 50 years ago, I was PD of WCMQ in Miami. The owner was so tired of the jocks "pot whipping" that he had the engineer build boards that had no level control. The mike was set hotter than the music channels, but otherwise the automatic gain gear took care of everything.
 
With today's processing equipment, it really does not matter where the "pot" is set. If it is too low, the AGC processing will pull it up. If it is too high or has excessive peaks, the compression and peak limiting will handle the excess.

Back 50 years ago, I was PD of WCMQ in Miami. The owner was so tired of the jocks "pot whipping" that he had the engineer build boards that had no level control. The mike was set hotter than the music channels, but otherwise the automatic gain gear took care of everything.
That’s quite interesting to know. There is definitely something going on at TDY however because sometimes they sound fine and other times they are extremely over-modulated.

I have to wonder if their equipment is old. This is a station who up until about 25 years ago broadcasted exclusively in mono as a talk station except on Friday evenings and Sunday mornings when they aired Sid Mark’s Sinatra program. It’s difficult to describe but I remember the mono signal was extremely flat and sounded like “old FM” on a one speaker tube radio from the 40’s if that makes sense.

With that said, I always wondered how they switched over to stereo when they aired Sinatra. Would they have used a back up stereo transmitter? Or was it done on the processing side? If it was done with a back up stereo transmitter then maybe WTDY is still using it today because it wouldn’t have gotten much use at all back in the 90’s and early 2000’s before the format switch.
 
That’s quite interesting to know. There is definitely something going on at TDY however because sometimes they sound fine and other times they are extremely over-modulated.

I have to wonder if their equipment is old. This is a station who up until about 25 years ago broadcasted exclusively in mono as a talk station except on Friday evenings and Sunday mornings when they aired Sid Mark’s Sinatra program. It’s difficult to describe but I remember the mono signal was extremely flat and sounded like “old FM” on a one speaker tube radio from the 40’s if that makes sense.

With that said, I always wondered how they switched over to stereo when they aired Sinatra. Would they have used a back up stereo transmitter? Or was it done on the processing side? If it was done with a back up stereo transmitter then maybe WTDY is still using it today because it wouldn’t have gotten much use at all back in the 90’s and early 2000’s before the format switch.
A station that can broadcast in stereo generally can turn the stereo on or off. Some stations have been known to go to mono for network news, then go back to stereo when it is over.

And some stations that have a few monaural audio elements may just leave the stereo function on. If everything in the studio is in phase, most listeners won't know or sense the difference.

I converted my first FM from mono to stereo in about 1966. It took a couple of hours to mount and wire the stereo generator and then we were all stereo (we had installed a stereo board previously). But we ran all the commercials in mono as back then the local agencies did not do stereo versions as we were the only stereo station in the country.
 
After driving through and hearing 96.5 on a radio, I can confirm something is off with the audio chain.

The processing has always been rough, but it now sounds like everything is being clipped and distorted. More noticeable on HD. The analog-to-HD blend is also a few seconds off.
 
After driving through and hearing 96.5 on a radio, I can confirm something is off with the audio chain.

The processing has always been rough, but it now sounds like everything is being clipped and distorted. More noticeable on HD. The analog-to-HD blend is also a few seconds off.
Some days it’s fine and others days it’s awful. I think someone over there is monitoring this board because two weeks ago I posted about the Acoustic Sunrise being extremely over modulated every Sunday and for the last two weeks it’s been fine. That said, they need to stop playing Adele in rotation until they figure out what’s going on because their processor can’t handle her voice. When Adele comes on the distortion is off the charts.
 
With today's processing equipment, it really does not matter where the "pot" is set. If it is too low, the AGC processing will pull it up. If it is too high or has excessive peaks, the compression and peak limiting will handle the excess.

Back 50 years ago, I was PD of WCMQ in Miami. The owner was so tired of the jocks "pot whipping" that he had the engineer build boards that had no level control. The mike was set hotter than the music channels, but otherwise the automatic gain gear took care of everything.

I've heard stations where the DB level for the AGC was set to high. That with the release set to short is a very bad combo. While I understand why stations are processed so heavily, I'm not a fan of it. You either have it stand out in cars or portible radios, or you let the audio breeze. There are tradeoffs either way. There are ways to set it up so audio can breeze while still having things sound consistent. On the rare ocasion I get to hear that, it makes me smile.
I haven't checked it out recently, but last year WAEB-FM sounded excelent both in analog and HD. Super wide dynamic. The only statioin in that iHeart cluster that sounded like that. It Didn't pump either.
 
I've heard stations where the DB level for the AGC was set to high. That with the release set to short is a very bad combo. While I understand why stations are processed so heavily, I'm not a fan of it. You either have it stand out in cars or portible radios, or you let the audio breeze. There are tradeoffs either way. There are ways to set it up so audio can breeze while still having things sound consistent. On the rare ocasion I get to hear that, it makes me smile.
I haven't checked it out recently, but last year WAEB-FM sounded excelent both in analog and HD. Super wide dynamic. The only statioin in that iHeart cluster that sounded like that. It Didn't pump either.
You are confusing AGC with limiting.

With AGC you set the “center point” at what should be the normal standard level. If the input averages too high, gain is reduced and low levels are increased. AGC is “gentle” and works on averages.

Then you have compression and peak limiting. Compression reduces peaks rapidly, making the peaks cut and thus causing lower levels to sound louder. Peak limiting violently cuts high excursions to prevent over modulation.
 
You are confusing AGC with limiting.

With AGC you set the “center point” at what should be the normal standard level. If the input averages too high, gain is reduced and low levels are increased. AGC is “gentle” and works on averages.

Then you have compression and peak limiting. Compression reduces peaks rapidly, making the peaks cut and thus causing lower levels to sound louder. Peak limiting violently cuts high excursions to prevent over modulation.
Ok, then the compression isn't set right in some ccases. I've heard the hiss between the kick drumb and something else, or after someone hits strings the levels rising unnaturally. To me it sounds like what would be the case if the release time is set too low.
 


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