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The Low Frequency Content Thread (films, games, music, etc)


maxmercy
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Even if I could reproduce that 1-2 Hz blob without my electronics rolling it off some 12dB, I doubt I would even notice anything in my concrete and brick room at all...might get a whoosh of air noise from many 18's very slowly attempting it. Maybe if you are on a suspended floor you might get a nice tactile shake. I mean we are talking 3 octaves below 10Hz here.

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Then again the question arises: Could it be detected if we could reproduce it cleanly? With harmonics at 2,3,4 Hz, who knows?

 

 

 

Good question, and amazing work JSS.

 

As I understand it, it could certainly be detected, even audibly, if reproduced with sufficient level.

 

I'm sure many here have seen several of the same works I've read, regarding audibility thresholds. It would appear several of these studies state it takes around 120dB-125dB for audibility at 3hz. But audibility is but one component of the experience, right?   B) These filmmakers present us with the material and we blend the tactile/visceral, with the audible and of course the visual. Well, at least some of the releases appropriately cover all the senses....  

 

 

My room/home excitation noises that accompany the biggest and deepest effects (even after I've tracked down all the biggest offenders), are still problematic. I seem to recall seeing somewhat similar spectral content in Open Range. The energy was all alone and high in level and centered way down deep in the single digits.

 

 

What's the thinking here? Is it the primary element of an effect, or merely a near DC pulse or displacement component of an effect that's fundamentally much higher? Either way it's interesting.  

 

 

 

 

JSS, as always, amazing stuff. Thank you for that.

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Thanks!

 

For effects that low, crowson transducers or a Thigpen may be the only option.

 

The waveform does not look like a DC pulse, more like a slowed-down-in-pitch explosion.

 

You have to give the TF crew a lot of credit. First very high level downward LF sweep that was the sole sound effect in a scene that I know of (I am not counting the 1977 Star Wars Death Star firing sequence, that was an upper bass sweep). Now downward sweeps are used ad nauseam, to the point of 'can't you think of anything else to throw in there?'

 

Looking forward to The new Star Trek.....

 

I should get Oz PvA'ed sometime this week, if everything goes right.

 

JSS

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I would think this may be noticed since it is the loudest bass of the event.  If it had loud midbass then you would never notice it at all.  Since this is a -10 to -15 dB bass effect it will only hit 100-105 dBs so we will only feel something.  Of course if one runs hot you will get 110-115 dBs.  Then add in the rolloff for 1-3hz and we are back down to 100-105 dBs again.  These are the reasons many don't care for ULF because all this work for subtle events.  I know my system would be flat to 3-4 hz if I had less rolloff from my measuring gear and sound card. 

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James, thanks for the SL graphs.  Pretty much confirms what I was hearing.  Are you still working on going through the list of movies that don't have graphs & caps for the databass of movies being built here?

 

John, I know this is kinda a large request, but, when you have time, could you describe in detail how you removed all rolloff in your measurements, so that we might attempt to do the same?

 

FOH, agree across the board with your assertions on audibility and tactile response adding to the experience.  Good stuff, as always.  Another movie that had this type of content, but is not in my library, is The Hitchhiker's Guide to the Galaxy.  As noted on the original AVS MWB thread, it's during "Two Guys Strapped to Pillars, Chap 6 (0:22:58)."  Here's the graph for posterity's sake:

 

Hitchhikers_ch6_22.jpg

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I'd like to request screencaps for Red Tails. It had garnered a couple mentions in the AVS thread, but I think it's been largely overlooked. Not Up there with the BIG BOYS, but I think it has more than a few scenes worth capturing. I can provide timestamps if needed.

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I don't own that one and have never seen it.  I want to go through the lists that I own first.  Remember, I will do these and watch movies too, I need to use the system once in a while. 

 

Anyone know what the next step is for doing a speclab graph from my subs rather than the disc?  I have an idea but want to make sure.  I will still be 5 dBs low under 5hz.  I need new measuring gear.  So if direct to disc has -5 dBs under 5hz adding my mic and sub amps will add more, well, not the amp.  I might be 10 dBs down at 3hz with my gear.  When I run a sweep it just dives after 6hz meaning my gear will rolloff.  I am only down 1.6 dBs at 10hz from 20hz and 2 dBs at 6hz but then it drops like I have a ported system and I don't.  You can see my processor and PS3 together with my sound card are down 5 dBs under 5hz already. 

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I don't own that one and have never seen it.  I want to go through the lists that I own first.  Remember, I will do these and watch movies too, I need to use the system once in a while. 

 

Anyone know what the next step is for doing a speclab graph from my subs rather than the disc?  I have an idea but want to make sure.  I will still be 5 dBs low under 5hz.  I need new measuring gear.  So if direct to disc has -5 dBs under 5hz adding my mic and sub amps will add more, well, not the amp.  I might be 10 dBs down at 3hz with my gear.  When I run a sweep it just dives after 6hz meaning my gear will rolloff.  I am only down 1.6 dBs at 10hz from 20hz and 2 dBs at 6hz but then it drops like I have a ported system and I don't.  You can see my processor and PS3 together with my sound card are down 5 dBs under 5hz already. 

No rush at all. If you can get around to it eventually, that's cool.

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How would the sound designers even put something like that on the disc? They didn't record that. So then do they do it digitally? But what kind of synth gear will let you put a blob of 1.5hz content in there?

 

Would be cool to experience that. I don't think I'll ever chase those hz. A thigpen isn't on my list of upgrades. I don't even really concern myself with 5hz. I just let the subs do what they do below 15hz. If they make output great.

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Max,

What do you think I need to do for my rolloff?  Everytime I tried the tutorial I get massive purple noise when checking the subtract box. 

 

The rolloff compensation boosts enough that noisefloor is brought up, I think......

 

Are you positive you followed the steps exactly as in Post #4 of the Waterfall Tutorial?  Remember, you will calibrate at a HIGHER level than you will playback at for rolloff compensation.  That may be your problem.

 

JSS

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How would the sound designers even put something like that on the disc? They didn't record that. So then do they do it digitally? But what kind of synth gear will let you put a blob of 1.5hz content in there?

 

Would be cool to experience that. I don't think I'll ever chase those hz. A thigpen isn't on my list of upgrades. I don't even really concern myself with 5hz. I just let the subs do what they do below 15hz. If they make output great.

According to FilmMixer, most of the infrasonic content in movies these days are created using 2-3 popular programs. They don't bother recording content down that low.

 

 

Max

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Just did it again and here is what happens.

 

capt1306190440_zps8f9be662.jpg

 

 

If you unclick 'Subtract Reference Spectrum' What do you get?

 

This is weird.  Do you use a desktop or laptop?  IS it plugged in or running on battery power?

 

This is AFTER turning back down to measurement volume, right?  Or is this still at the 10dB higher rolloff calibration volume?

 

 

JSS

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According to FilmMixer, most of the infrasonic content in movies these days are created using 2-3 popular programs. They don't bother recording content down that low.

 

 

Max

 

I'm glad some still do it....it just seems like a waste to create a sound effect that will just get a filter placed on it during the mixing process in order to take part in the loudness war.

 

JSS

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This was with the MV 10 dBs lower. My computer is a desktop and plugged in. You can see it makes the average graph flat to 1 hz but purple in color. When I uncheck the subtract box the purple goes away bu so does the low end boost. After watching my peak graph during the sweeps I know my sound card has a 10 dB per octave rolloff starting at 20hz! This is why you are seeing purple be quad I calibrated using 3 and 5 hz assuming the rolloff worked and that made 20hz and above 10-20 dBs hot! 10 hz is down 5 dBs and 5 hz at 20 dBs. My 2.5 hz is down 30 dBs as a watch the peak levels during the sweeps. Damn!

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The way I do it is a PITA, but it is absolutely bit for bit accurate (it takes about the same amount of time as running the film while measuring PvA, about 2 hrs to set up for SpecLab and WaveShop).  What is on the disc is measured without any signal chain.  There may be a utility which simplifies the generation process that someone is looking into.

 

JSS

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