Automatic Television Commercial Volume Limiter/Regulator

[arizonaguide]

WOW what a great site! Okay, folks...let me ask a question:

My next project is going to be a Television Audio volume regulator to keep my TV output at a constant volume range.
I cannot BELIEVE the way that the networks are allowed to CRANK to volume levels on the "commercials" to double (and triple) the volume that you have set.

Does anyone share this problem?

So, has anyone seen or designed a circuit that can be placed on the "stereo out" of the Cable Box (before it enters the Audio system) that will Monitor and REGULATE the stereo audio volume (as it comes out of the cable box) to a set range that is tolerable to my ears...and put a stop to the way that the "commercials" are allowed to be triple the volume of the current volume setting that I have chosen

To my understanding there used to be a law against the networks doing that (amplifying the commercials) but somehow that law seems to have disappeared...and the result is hearing loss and discomfort from loud television commercials.

Any ideas?

 

[arizonaguide]

Something along these lines:
**broken link removed**

Stereo in jacks, and VOLUME REGULATED Stereo out!

 

[arizonaguide]

It was mentioned:

The TV stations already use a volume limiter. It limits the peak volume so that the average volume is much higher. It is called an audio compressor.

Does that mean that they are not actually amplifying the PEAK VOLUME outside of my current settings, but are instead just cranking the "average" volume when they show a "commercial"? Because it sure feels like they are doubling or tripleing the volume of the commercials.

So, what's my solution?

I also notice a big difference between the stations. Big volume changes from one station to the next. I was hoping my idea would "normalize" the volume levels to one-set-comfortable level range, as it comes out of the Cable Box.

 

[audioguru]

If you had the details of their compressor (impossible) you could make an "audio expander" that does the exact opposite. Then simply use a peak limiter circuit to keep the volume the same for every show or channel.

 

[Nigel Goodwin]

Do like everyone else does, mute the volume during the adverts - increasing the perceived volume is completely counter productive.

 

[killivolt]

Do like everyone else does, mute the volume during the adverts - increasing the perceived volume is completely counter productive.

I want my own commercials like at a football game just the funny ones.

It uses an automatic kick the f..... out of the current commercial and replaces it with my funny one, meanwhile it monitors the over powering unregulated volume of the previous commercial while waiting for program to back on and resuming my leisurely comfortable evening.

kv

 

[arizonaguide]

I hear ya about hitting the "MUTE" like everyone else...BUT I'm getting tired of the BLAST of volume I get while I'm reaching for the MUTE button (actually usually the FastForeward)...and I shouldn't have to try to fumble for the damn thing in the dark anyway...(and it angers me everytime I have to!).

There has to be a Volume "normalizer" circuit out there that will keep all "stereo out" from the Cable Box "clipped" down withing a certain range. Or, at least limit the peak volume to one that I have pre-set on this newly created secondary "REGULATOR box"...now to figure out the circuit.

Doesn't the music industry have something similar that "regulates" a normal RCA type stereo out peak signal to within a certain range.

In addition the volume on the Cable Box itself this should be a secondary circuit that will monitor the output signal, and "CLIP" the peaks IF they're above a certain threashold...but leave the stereo signal alone if it's NOT above that threashold.

YES it would be nice to automatically "MUTE" them completely...but how do you design a circuit that tells the difference between the show and the commercial? So, I'll just be happy to avoid the BLAST of volume. It's only until I can get my hand on the FastForward button anyway...but that's 1 or 2 seconds of Triple Volume hell, that I'm just sick of putting up with!

 

[Nigel Goodwin]

Many modern sets have such circuits in already - but they way they function means it's not foolproof, and many people turn them OFF due to their effects on the programme sound.

I understand that the situation is worse in the USA, with regulations about advert volume been more lax than the UK.

 

[arizonaguide]

YES, it's gotten intollerable!

it monitors the over powering unregulated volume of the previous commercial while waiting for program to back on and resuming my leisurely comfortable evening.

I couldn't have said it better myself!!

a "BLAST limiter", if you will.

After that circuit works, then I'll work on figuring out how to amplify the actual "speaking track" on the show, and minimize the "surround" sound of the damn city-bus-noise in the "realistic" <choke> "surround sound" that we have now...that drowns out the actual storyline. But, that's another project still.

Bottom line: I'm getting OLD, hard of hearing (from loud commercials), and contankerous.

 

[audioguru]

Most modern rock and roll music is compressed. Do you want your TV to mute it?

 

[arizonaguide]

So, I'm confused. What exactly is "compressed" audio?

To my hearing, they are still INCREASING the actual volume during commercial time, correct?
So, wouldn't a secondary (post-cable-box) peak limiter on the cable-audio-out solve this problem?

 

[arizonaguide]

See, I guess it HAS to be a secondary circuit after the cable-box.

Because, they trick me into setting the cable-box volume at level 5 to hear the show, then they BLAST the commercial at level 10, then drop back to 5 for the show. (sure, maybe broadcast limit is 10...so they aren't illegal...but somehow they have convinced the station to broadcast the show at half volume in relation to the commercials).

There has to be a way of regulating the volume and "normalizing" it....in effect, getting the shows and the commercials at the SAME max-peak level. Or in other words the commercials peaks limited to the "average" volume level of the show.
Perhaps a volume "averager" is more correct?

So, if I had a post-cable-box Volume Peak Limiter that would chop everything OVER level 5 back down to level 5 that should do the trick. Manual Muting just won't work (frustrating!)...and autoMuting is not realistic/functional.

 

[audioguru]

So, I'm confused. What exactly is "compressed" audio?

The peak levels are reduced then the average level is increased.

To my hearing, they are still INCREASING the actual volume during commercial time, correct?

They inctrase the average volume but the peak volume remains the same.

So, wouldn't a secondary (post-cable-box) peak limiter on the cable-audio-out solve this problem?

No.
Because the peak volume is not higher with compressed audio compared with normal audio.

 

[arizonaguide]

Okay, I think I understand. It's an "averaging" thing.

So, you are saying the commercials have no higher volume PEAKS than the show, just everything in the commercial is cranked up to near-maximum. In other words, what you are saying is the average amplitude of every sound in the commercial's signal is NEAR MAXIMUM, where as the typical television show still has a near-max PEAK, but only occasionally when the car blows up (or some other loud event).

So the AVERAGE (wave body?) of the commercial is a higher volume, but not the peaks. Damn. That does make it difficult to solve...as there is no way to automatically tell the difference in the signals...or no way to just chop the painfully high "peaks".

But, there's got to be a solution. I refuse to give up!
So it has to be a solution that involves a reduced "averaging" somehow...hmmmm. (thinking/pondering)



There are $40 electronic hearing protectors that will allow me to hear a conversation, yet cut out the sound of a loud running saw (with a longer running "average") or a gunshot (peak).
I wonder if that circuitry is a PEAK LIMITER or if it uses averaging somehow...because I can still hear low "conversational" volumes, but it muffles the loud gunshot. Interesting.

 

[caster.cp]

There actually is a solution.

Mute it

Do you know the story about the space pen? Although not true, it's enlightening.

 

[gary350]

It is illegal for the advertisements to be louder than the TV show. I had it too, it makes me mad ads seem like they are 2 times louder than TV shows.

Here is how it worked 20 years ago and I assume it still works like this. TV shows want good quality sound so they use Class A amplification. Advertisements do not need good quality sound so they use a lesser quality amplification like class B amplification.

The power rating of Class A and Class B amplification have to be the same to be legal. You might need to read about class A and class B amplification to understand what I am about to try and explain. The peaks of the sine waves are cut off on class B amplification this allows the power to be turned up to get the same power rating as class A but the TV speaker sees it as a louder signal so it IS LOUDER.

I have always wanted to build a compressor for my TV but just never got around to it. Now I push the mute button. There are so many advertisements these days 10 minutes worth sometimes I have plenty of time for other things, pop so pop corn, take a shower, take out the trash, all sorts of things so I make use of those long advertisements that I HATE.

 

[audioguru]

It is illegal for the advertisements to be louder than the TV show. I had it too, it makes me mad ads seem like they are 2 times louder than TV shows.

Here is how it worked 20 years ago and I assume it still works like this. TV shows want good quality sound so they use Class A amplification. Advertisements do not need good quality sound so they use a lesser quality amplification like class B amplification.

The power rating of Class A and Class B amplification have to be the same to be legal. You might need to read about class A and class B amplification to understand what I am about to try and explain. The peaks of the sine waves are cut off on class B amplification this allows the power to be turned up to get the same power rating as class A but the TV speaker sees it as a louder signal so it IS LOUDER.

You are completely wrong about class-A and class-B. A class-B amplifier has almost the same peak signal level as a class-A amplifier . The class-B amplifier has crossover distortion at low levels, not clipping at high levels.

Commercials are compressed. Then their average volume is much louder but the peak power is the same as before.
Compression reduces the gain at higher levels but not as harsh as clipping.

 

[caster.cp]

Then their average volume is much louder but the peak power is the same as before.

Then it would work to limit signals by their RMS level, I presume (measured, for example, by one of the magical but overwhelmingly expensive Maxim's true-rms to dc ICs).

 

[chemelec]

Do a Search for an ALC Circuit. (Automatic Level Control)
It will correct that Loudness.
Not too difficult to build. Also Very Inexpensive.

Usually its a Peak Voltage Detector, Controlling a Fet to act like a Variable Resistor in Series with antor resistor, Essentally creating a Volume Control.
To Maintain a Constant Maximum Volume.

There Was an IC that actually did this, But Discontinued now.
Not sure on Origional Part Numbers, But there was also a Replacement Part "ECG1179" that worked Simular, but no Fet. Using transistors instead.
(I have the Internal Schematic of this ECG1179.)

These were very commonly used on the Record function on Older Cassette Recorders to Prevent Overload on Record.

 

[arizonaguide]

Averages, peaks, Class A and B all set aside...I know damn well that the decibels coming out of the speaker during commercials is many times more than that of the SHOW itself...and it has gotten to the level of PAINFUL here during my attempt at a nice comfortable evening...almost to the point of boycotting cable TV use.

Combine that with the frustration of scrambling for the MUTE button (in the dark) fast enough to NOT get BLASTED by the first few seconds of each commercial (and then the resulting tide of anger that washes over me!) means it's time to be smarter than the unethical advertizing dirtbags...and engineer a solution!