maxmercy

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

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Hey Max, Here is TF1 megatron blasts Jazz on the BEQ version.

 

 

capt1506040248_zpszsrfuw9d.jpg

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How do I graph the digital version to compare to my mic'd version?

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How do I graph the digital version to compare to my mic'd version?

One way is to use jriver to convert the track to a mono wav and then play that through speclab.

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Yes, I have done that before but can I select something within spec lab from the input and output? 

go to File/Audio Files & Streams/ Analyse and Play File (with DSP) and choose the wav from the file dialog

 

remember to switch your mic cal filter to bypass

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What are you guys using to calculate them then?

 

The algorithm used is one I came up with myself with help from several members here.  The basics are laid out in the first post, the details are cumbersome.

 

JSS

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Hey Max, Here is TF1 megatron blasts Jazz on the BEQ version.

 

 

capt1506040248_zpszsrfuw9d.jpg

/

How do I graph the digital version to compare to my mic'd version?

 

Digital version here:

 

post-20-0-78922800-1371522000.jpg

 

The color scheme is not the same, and the magnification is much higher, but the content below 5Hz is hotter than anything above for that blast.  One of the biggest system rolloff challenges I have encountered.

 

Oh yeah....this is the non-BEQ version.  BEQ is ridiculousness.

 

JSS

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Hey man, sorry to hear about the medical stuff.  A string of my family members have logged some ER time lately too and few things are less fun. 

 

As far as speclab goes, there is a bug that I know about for the latest version where if your system runs 24bit audio, you have to select 16bit in the settings on SL or it will give you all kinds of crazy noise and stuff.  Maybe it's that? 

 

I don't know about audacity but you can loop your soundcard's out to in, use REW to generate different sine tones and see if they register at the same levels on the graph in Audacity. 

 

Thanks. It gave me some perspective when the ER duty nurses came to know me on sight. Wish the hospice nurse would be so kind as they are.

 

I think I managed to get SL to work. That trick was part of the solution. I still don't trust going with an analog loop, but by ripping my audio to a .wav, downconverting to mono and using the analyze audio file function, things started to work correctly. Test tones are finally showing at the correct frequency and without harmonic duplication and the spectrums are lining up with Audacity's, so I think I'm finally good to go.  Since I've been looking at music anyways rather than BluRays, this won't be a hindrance at all.

 

 

So, with one last look back at that track, "Radiation", Audacity says this:

 

ofppCWV.jpg

 

Another spectrum program shows this:

 

RiCCZOZ.jpg

 

 

And SL is showing this at the beginning of the track:

 

agtxt4M.jpg

 

(Default -60dB-0dB color scale.)

 

For a total track spectrum of this:

 

82PjMFD.jpg

 

Got to love it when the frequency is so low that each signal peak shows in the amplitude bar.

 

Looks like things are pretty much in agreement now. I think I can trust the output finally. Yep, I still like this track as a ULF demo, strong output and little of that cheap 30Hz+ bass that's easy to produce to excess.

 

 

Audacity is accurate and equivalent to SL for the FFT settings entered.  I use it.  Powerful piece of software for free.  Donate to the development team if you can, as well as REW's.

 

JSS

 

That's what I'm wondering about, though. When I check the spectrum of, say, a 15 second clip in Audacity, I'm seeing some frequencies reading as around 4dB higher at some frequencies than when doing the whole 237.8sec analysis (-7dB vs-11dB at a particular frequency on one audio track, as an example). Lower, I could understand, higher and I'm wondering how Audacity does its "Plot Spectrum". Does it do some sort of averaging or sample skipping?

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It averages the whole sample you choose.  It has to; with no waterfall to show time, you get an average over the whole time selected.  Given that, SpecLab's red graph for a given timeframe will match closest to Audacity's Spectrum function with equal FFT settings.  

 

SpecLab is gold for looking at spectral content.  You can get a waterfall, signal, peak and average all in one screen.

 

JSS

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It averages the whole sample you choose.  It has to; with no waterfall to show time, you get an average over the whole time selected.  Given that, SpecLab's red graph for a given timeframe will match closest to Audacity's Spectrum function with equal FFT settings.  

 

SpecLab is gold for looking at spectral content.  You can get a waterfall, signal, peak and average all in one screen.

 

JSS

 

Huh, so useful, but not so much for what I was looking for. Seems too difficult to get an objective measure using it if the plotted spectrum is dependent upon what is selected. Shame, I was hoping for the peaks as that's more useful in our aspect of the hobby and the peaks are the peaks regardless of the average. SpecLab does look great, I just wish it were a bit more idiot friendly for folks like me.
 
Anyways on a different note...
 
If there are any ULF hipsters out there who've always wanted to say "War of the Worlds? Too mainstream. I only test my subwoofer with geophone recordings of an abandoned cement plant on the Sino-Russian border. You've probably never heard of it." then you may want to take a break from Instagramming your sriracha chard stem fridge pickles and give a quick look at Jan Ryhalsky - Iron Skeletons
 
Alas, the recordings aren't available on cassette like some of the other albums on this label, but the limited edition of thirty-three should keep some hipster cred going.
 
Caution: listening without a pre-existing beard may cause spontaneous growth of ironic facial hair.
 
Be real careful with this one. This is what you're getting right at the very start.
 
01 - "The Old Derrick":
 
ZFEH0V3.jpg
 
xCj28m1.jpg
 
I'm not kidding about being careful, this is the first five seconds of the first album (it tames down quickly afterwards):
 
NVz1BHm.jpg
 
 
02 - "The Pipe in the Old Boiler House"
 
N5Hf7vS.jpg
 
rc7KDjk.jpg
 
 
To be continued...

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The remainder of Iron Skeletons:

 

05 - "Abandoned Pumping Station"
 
7f3vy2c.jpg
 
QtnH1tJ.jpg
 
06 - "The Ventilation Shaft in the Pump Station"
 
kxIgjwp.jpg
 
PVPolO2.jpg
 
Against the others, that's on the "meh" side, but ordinarily it'd be impressive.
 
07 - "The Metal Frame of the Pumping Station"
 
v8NgAuH.jpg
 
hhIeGPo.jpg
 
(Sorry about the skewed vertical scale here. I expanded it to get a better look and ended up overwriting my previous saved screen capture and closing everything before realizing it.)

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That looks like a test, for sure.  But anyone with a Reference capable system should handle that with ease (at cinema reference level), as they already have headroom built in due to LFE channel's specs.

 

JSS

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That looks like a test, for sure.  But anyone with a Reference capable system should handle that with ease (at cinema reference level), as they already have headroom built in due to LFE channel's specs.

 

JSS

Maybe so, but it's not common in movies to have strong 16 Hz sustained for such a long time.  At theatrical reference, it looks like that pushes 109 dB (or 111 dB, if you use 85 dBC with -20 dBFS RMS pink noise) for a long time.  That'll definitely warm up those voice coils.

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I didn't say I would do it.  I have better things to do than listen to recorded machinery (no matter how much bass) in my HT.  Now, giant robots, explosions, and a big green rage-monster using a police car as boxing gloves?  Pass the popcorn...

 

JSS

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That looks like a test, for sure.  But anyone with a Reference capable system should handle that with ease (at cinema reference level), as they already have headroom built in due to LFE channel's specs.

 

JSS

 

 

I didn't say I would do it.  I have better things to do than listen to recorded machinery (no matter how much bass) in my HT.  Now, giant robots, explosions, and a big green rage-monster using a police car as boxing gloves?  Pass the popcorn...

 

JSS

 

Cinema reference level for movies, but this is self-classified as music, very much out there "experimental" (still better than Cage) music, but music none-the-less and music does not have an industry standardized reference level. Many of us use our systems for more than playing the same three or four 20 second movie clips for the hundredth time in the past seven or ten years. Music listening being a particularly popular alternative to the same ol' same ol' that Hollywood loves to put out. 

 

Such was my case here: I'd been listening to classical, ran across this oddity and played it for laughs. That proved to be a mistake. Classical music isn't like modern pop where everything's as brickwalled as last summer's blockbuster. It's mixed at quiet levels quite often to preserve the sparse dynamics. Being down 20dB, even 30dB below the typical dime a dozen Baysplosion-esque film means that to recreate the concert hall experience requires turning the volume up, way up, above normal reference levels. My volume was up, I played this track and by the time I had grabbed the remote I was already in need of a quick trip to the store to buy new lightbulbs to replace those in the next room that suffered the most from the experience.

 

Because these recordings are so out there and yet surprisingly high fidelity, I wanted to share the humor of them, but I didn't want to be responsible for causing anyone grief with their systems. You can be as reference capable as you want, but there are several factors that made these dangerous on a blind click. The first is that there is no warning, no gradual buildup in levels or visual information on the screen to indicate what's coming. You hit play and get this:

 

ydVtS3pl.jpg

 

The signal builds up fast with no warning where it'll stop. As you can also see, this isn't a quick little passing rumbly whump of Hollywood's impression of an explosion. It's a recording of a huge highly resonant piece of metal, in other words, a bell, a source of just about the nearest thing to a pure sine wave nature can muster. A long-duration pure sine wave nearly at 0dB, as SME noted, that's how you burn out drivers. Then you must consider the frequency that all this is happening at: ~15Hz. If I were to design something to kill ported subs, I'd probably pick that frequency: just low enough to be below port tune on most all designs leaving the driver to unload, but just high enough to escape the range where protective HPFs have the greatest effect.

 

Were this a later track, I'd have not made any mention of caution and offered the stuff as entertainment for those of us not afraid to laugh at ourselves while enjoying something a little (ok, a lot) out of the ordinary or to satisfy genuine curiosity for others. Afterall, some of us want more stimulation and something new every once in a while than watching the same darned clip of Hulk smashing cars seven years after it first started boring audiences and flopped in the theaters.

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Such was my case here: I'd been listening to classical, ran across this oddity and played it for laughs. That proved to be a mistake. Classical music isn't like modern pop where everything's as brickwalled as last summer's blockbuster. It's mixed at quiet levels quite often to preserve the sparse dynamics. Being down 20dB, even 30dB below the typical dime a dozen Baysplosion-esque film means that to recreate the concert hall experience requires turning the volume up, way up, above normal reference levels. My volume was up, I played this track and by the time I had grabbed the remote I was already in need of a quick trip to the store to buy new lightbulbs to replace those in the next room that suffered the most from the experience.

Can you name any recordings that you routinely play at 20-30 dB above theatrical reference?  That seems a bit exaggerated.  For a stereo track that allows peaks of up to 125-135 dB.  That seems just a bit extreme, unless you want to hear the concert from the perspective of the percussionist as opposed to the front row seats, for example.

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Afterall, some of us want more stimulation and something new every once in a while than watching the same darned clip of Hulk smashing cars seven years after it first started boring audiences and flopped in the theaters.

Nice....quite the mental leap into my personal listening tastes there. I meant no disrespect towards the recordings you suggested, just that it would not be something I would choose to purchase.

 

I love classical music, but would never play anything at +20dBRef without auditioning it at a much lower level. I am fully aware of my system's capabilities and limitations, and letting a recording have its way with my equipment with possible 131dB redirected peaks (105dB +20dB above Ref, +6dB due to L/R summed bass redirected to subwoofer) is not something I would do.

 

Thanks for the graphs.

 

JSS

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Can you name any recordings that you routinely play at 20-30 dB above theatrical reference?  That seems a bit exaggerated.  For a stereo track that allows peaks of up to 125-135 dB.  That seems just a bit extreme, unless you want to hear the concert from the perspective of the percussionist as opposed to the front row seats, for example.

All my music is analyzed according to R128 volume leveling standards. In order to play the quietest song (Felix Hell - Organ Sensation - Guilmant: Sonata No. 1 in D minor: II. Pastorale) the same volume as the loudest song (Godsmack - Faceless) requires a 33.9 dB adjustment in volume. With 24-bit recordings, stereo tracks can easily have their average levels down 30+ dB from peak. The capability of your equipment and how high you turn it up determines the peak volume, not the encoded levels. Playing 20-30 dB above theatrical reference just means the song was encoded that much quieter to give room for dynamic peaks. 

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Can you name any recordings that you routinely play at 20-30 dB above theatrical reference?  That seems a bit exaggerated.  For a stereo track that allows peaks of up to 125-135 dB.  That seems just a bit extreme, unless you want to hear the concert from the perspective of the percussionist as opposed to the front row seats, for example.

 

Not above, below. I was referencing quiet recordings that to play back at closer to concert levels need the volume goosed a great deal. If it's a victim of the loudness wars, the volume gets turned down; an exceptionally softly recorded string piece like I had been playing, it needed to be turned way up. I wasn't listening like I was up on the stage (which has had me want to cover my ears in the past when I've had the opportunity [my sister used to play in a symphony]), but I wasn't going to leave it at my typical movie listening level and have it sound like I was listening from the concert hall's parking lot. The peaks may remain the same when level matched, but they'll take different settings of the volume to get there. Else what's the point of having a volume knob in the first place? Music doesn't have the same level standards as do movies.

 

Nice....quite the mental leap into my personal listening tastes there. I meant no disrespect towards the recordings you suggested, just that it would not be something I would choose to purchase.

 

I love classical music, but would never play anything at +20dBRef without auditioning it at a much lower level. I am fully aware of my system's capabilities and limitations, and letting a recording have its way with my equipment with possible 131dB redirected peaks (105dB +20dB above Ref, +6dB due to L/R summed bass redirected to subwoofer) is not something I would do.

 

Thanks for the graphs.

 

JSS

 

Not so much of a leap; I tried to read your post from different angles as being an attempt at a joke, but couldn't make it work that way. It hit a nerve in that it was the exact same tone as those that eventually drove me away from the being a multi kilo-count poster on audio forums years ago and into becoming an audiophile hermit. It was always the same smug dismissiveness anytime mention was made of something that wasn't Jazz in the Pawn Shop, Diana Krall, forty year old yacht rock remasters or whatever the critics' darlings of the month were that seemed to always be immaculately recorded, exceptionally bland albums that managed to be less desirable than listening to a geriatric talk about bowel movements.

 

Good portion of my music collection ripped to my PC, PC fed into system, music played back on random play, pause playback very briefly to listen to the oddball and...BLLRRRRPPT. This isn't something ritualized like playing vinyl with plenty of opportunity to prepare and double check levels or even taking the time to pop a disc into the player. Anyone streaming the, well, streaming audio would be doing something similar in a similar setup and unless they're far into the OCD end of the behavioral spectrum checking all settings in three sets of three could easily end up in the same situation. It happens, it's life and life is sloppy since we're not mechanized in our actions. Screw ups happen and if typing a few extra words saves someone a few hundred  to a couple thousand in damages? I'd be an ass to dismiss the need.

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All my music is analyzed according to R128 volume leveling standards. In order to play the quietest song (Felix Hell - Organ Sensation - Guilmant: Sonata No. 1 in D minor: II. Pastorale) the same volume as the loudest song (Godsmack - Faceless) requires a 33.9 dB adjustment in volume. With 24-bit recordings, stereo tracks can easily have their average levels down 30+ dB from peak. The capability of your equipment and how high you turn it up determines the peak volume, not the encoded levels. Playing 20-30 dB above theatrical reference just means the song was encoded that much quieter to give room for dynamic peaks. 

 

Thank you for this great post.

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Not above, below. I was referencing quiet recordings that to play back at closer to concert levels need the volume goosed a great deal. If it's a victim of the loudness wars, the volume gets turned down; an exceptionally softly recorded string piece like I had been playing, it needed to be turned way up. I wasn't listening like I was up on the stage (which has had me want to cover my ears in the past when I've had the opportunity [my sister used to play in a symphony]), but I wasn't going to leave it at my typical movie listening level and have it sound like I was listening from the concert hall's parking lot. The peaks may remain the same when level matched, but they'll take different settings of the volume to get there. Else what's the point of having a volume knob in the first place? Music doesn't have the same level standards as do movies.

 

 

Not so much of a leap; I tried to read your post from different angles as being an attempt at a joke, but couldn't make it work that way. It hit a nerve in that it was the exact same tone as those that eventually drove me away from the being a multi kilo-count poster on audio forums years ago and into becoming an audiophile hermit. It was always the same smug dismissiveness anytime mention was made of something that wasn't Jazz in the Pawn Shop, Diana Krall, forty year old yacht rock remasters or whatever the critics' darlings of the month were that seemed to always be immaculately recorded, exceptionally bland albums that managed to be less desirable than listening to a geriatric talk about bowel movements.

 

Good portion of my music collection ripped to my PC, PC fed into system, music played back on random play, pause playback very briefly to listen to the oddball and...BLLRRRRPPT. This isn't something ritualized like playing vinyl with plenty of opportunity to prepare and double check levels or even taking the time to pop a disc into the player. Anyone streaming the, well, streaming audio would be doing something similar in a similar setup and unless they're far into the OCD end of the behavioral spectrum checking all settings in three sets of three could easily end up in the same situation. It happens, it's life and life is sloppy since we're not mechanized in our actions. Screw ups happen and if typing a few extra words saves someone a few hundred  to a couple thousand in damages? I'd be an ass to dismiss the need.

 

I guess the joke did hit a nerve.  No dismissiveness, just that recordings of old or abandoned machinery will likely not get purchased by me.  Your posts and signal graphs are relevant in an LF content thread.  I'll walk on eggshells from now on when replying to your posts, knowing how exposed the nerves are, and be supportive as to your contributions.

 

Now I'd be an ass to omit this statement: anyone who plays back material at a level knowing that a significant peak or prolonged high level in the signal could damage their system without auditioning the track at a lower level or running it through Orban or any other software beforehand to determine potential damage risk is taking a risk.  Random play or not, listening preferences or not, OCD or not.  I built my own speakers, and won't subject them to anything that they would not be able to handle, accidental or not.  Other folks' preferences obviously differ.  If a recording I have never listened to before sounds quieter, I'm pretty sure +20dBRef is not in the cards before I know nothing in the track will harm the system.  Call me careful.

 

This extrapolation of a post to my own listening preferences baffles me, and makes me wonder if your words sound dismissive now.  Read the thread from the beginning, and you will realize that there is a little more than loudness war-type movies in my most liked tracks.  Or not, and declare yourself an expert in the field anyway.    

 

Either way, welcome to the forum.

 

 

JSS

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