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Dolby TrueHD vs. DTS-HD Master Audio - Page 2

post #31 of 105
Quote:
Originally Posted by Roger Dressler View Post

Which discs were filtered, and how do you know?
Surely the most famous example is the Master and Commander blu-ray. You can tell quite easily by listening to the first battle scene on the DVD for comparison. It's a HUGE difference. I own both discs. The DVD makes an excellent demo disc (for audio). It's one of the most engaging action scenes I've ever experienced in a movie. You FEEL each cannon blast. The same scene on the blu-ray is bland and uninvolving. It feels like just another battle sequence. Despite the dramatic improvement in picture quality, the neutered blu-ray has near zero replay value. I'll reach for the DVD every time.
post #32 of 105
Great surround mix on M & C as well.
post #33 of 105
Quote:
Originally Posted by pitviper33 View Post

Surely the most famous example is the Master and Commander blu-ray. You can tell quite easily by listening to the first battle scene on the DVD for comparison. It's a HUGE difference. I own both discs. The DVD makes an excellent demo disc (for audio). It's one of the most engaging action scenes I've ever experienced in a movie. You FEEL each cannon blast. The same scene on the blu-ray is bland and uninvolving. It feels like just another battle sequence. Despite the dramatic improvement in picture quality, the neutered blu-ray has near zero replay value. I'll reach for the DVD every time.
Yes, that is well known. Kain made it seem as if this happens routinely.
post #34 of 105
Quote:
Originally Posted by Kain View Post

Good discussion! I have a slight off-topic question though. Why do some movies on DVD/Blu-ray Disc have the bass filtered? Is it to "protect" home theaters?
Quote:
Originally Posted by Roger Dressler View Post

Yes, that is well known. Kain made it seem as if this happens routinely.

Are you suggesting that it doesn't happen routinely? It certainly does. The M&C blu ray is just a particularly easy to demonstrate example of the effect it can have on the viewing experience. The real world contains lots of very low frequency bass. The microphones used to record real events pick up that bass. So anytime it doesn't make it to the disc, it must have been filtered out. Is that done to "protect" home theaters? I have no idea. I hope not, as it's very a misguided effort if so.

Kain sure has managed to send us off topic...
post #35 of 105

i can't even tell the difference the from the two formats lol.

I'm in early 30's so i probably loss some hearing over the years :P

post #36 of 105
Quote:
Originally Posted by pitviper33 View Post

Are you suggesting that it doesn't happen routinely? It certainly does. The M&C blu ray is just a particularly easy to demonstrate example of the effect it can have on the viewing experience. The real world contains lots of very low frequency bass. The microphones used to record real events pick up that bass. So anytime it doesn't make it to the disc, it must have been filtered out. Is that done to "protect" home theaters? I have no idea. I hope not, as it's very a misguided effort if so.
We are not discussing the filters that may have been used in the making of the original soundtrack. For a home release, unless one can compare it to the theatrical version, or as in the case of M&C, detect or measure the difference between two versions, there is no easy way to know if filtering was applied for a given home release or not.
post #37 of 105
Quote:
Originally Posted by Roger Dressler View Post

Quote:
Originally Posted by pitviper33 View Post

Are you suggesting that it doesn't happen routinely? It certainly does. The M&C blu ray is just a particularly easy to demonstrate example of the effect it can have on the viewing experience. The real world contains lots of very low frequency bass. The microphones used to record real events pick up that bass. So anytime it doesn't make it to the disc, it must have been filtered out. Is that done to "protect" home theaters? I have no idea. I hope not, as it's very a misguided effort if so.
We are not discussing the filters that may have been used in the making of the original soundtrack. For a home release, unless one can compare it to the theatrical version, or as in the case of M&C, detect or measure the difference between two versions, there is no easy way to know if filtering was applied for a given home release or not.



They forgot to filter this movie. This movie was made in the early 1950's!


post #38 of 105
Quote:
Originally Posted by Roger Dressler View Post

We are not discussing the filters that may have been used in the making of the original soundtrack. For a home release, unless one can compare it to the theatrical version, or as in the case of M&C, detect or measure the difference between two versions, there is no easy way to know if filtering was applied for a given home release or not.
You obviously took a far more narrow view of the question than I did. It wasn't nearly specific enough to call his question invalid as you seem to be trying to do. The content on many discs is HPFed. The question is why.

If you don't know the answer, fine. Neither do I; I just have a guess or two. If you do know the answer, please enlighten us. If you have some piece of information that might help us narrow in on the answer, such as at what stage this filtering is taking place as you've alluded, why don't you share it? It'd be a lot more constructive than just telling the OP he's wrong for asking the question and me that I'm wrong for defending the question.
post #39 of 105
I recall reading that Master and Commander was a mistake that slipped through QA. That was a couple of years ago in a discussion at blu-ray.com and I don't remember the source of that information, although I do remember it was someone credible.

Sent from my ADR6400L using Tapatalk 2
post #40 of 105
Quote:
Originally Posted by pitviper33 View Post

You obviously took a far more narrow view of the question than I did. It wasn't nearly specific enough to call his question invalid as you seem to be trying to do. The content on many discs is HPFed. The question is why.
If you don't know the answer, fine. Neither do I; I just have a guess or two. If you do know the answer, please enlighten us. If you have some piece of information that might help us narrow in on the answer, such as at what stage this filtering is taking place as you've alluded, why don't you share it? It'd be a lot more constructive than just telling the OP he's wrong for asking the question and me that I'm wrong for defending the question.

You're kinda missing Roger's point. If particular sound effects were high passed when created, before the movie was even mixed, or if the soundtrack was high passed when it was created for theatrical distribution the fact that they seem to be high passed on bD eans nothing about manipulation of the track when preparing it for home release. That's all he's saying. And at least in some contexts I've seen the discussion foused more on whether the moie is high passed than whether it was high passed for home release. Nothig wrong withbeing logically consistent about those things. And it makes no sense to complain about filtering a movie for home release if it was not filtered for home release, but instead was filtered when originally mixed and released to theaters.
post #41 of 105
Quote:
Originally Posted by pitviper33 View Post

You obviously took a far more narrow view of the question than I did. It wasn't nearly specific enough to call his question invalid as you seem to be trying to do.
Here is the entirety of the OP's original question: >>Why do some movies on DVD/Blu-ray Disc have the bass filtered? Is it to "protect" home theaters?<< Notice the specific mention of protecting home theaters? Notice he did not ask why soundtracks in movie theaters have the bass filtered? It seems pretty clear that he was asking why content heading home gets the bass filtered.

His question assumes filtering is the case. We all know about one famous example, M&C. Is he asking why it ever happened like in M&C? That one was investigated (I was one of the folks who did such investigation, and posted my findings). Or is he asking why it happens more frequently? To find out, I merely asked how one determines a given disc was filtered absent access to the theatrical source or another version (or some post-house insider information). Until we hear back from Kain, the question remains open.
Quote:
The content on many discs is HPFed. The question is why.
If you are asserting many soundtracks are being filtered for home use, then please cite the evidence. If you are asserting that many movie soundtracks as released to theaters have HP filtering, that is a different matter altogether. I will assume the latter in my reply below.
Quote:
If you don't know the answer, fine. Neither do I; I just have a guess or two. If you do know the answer, please enlighten us. If you have some piece of information that might help us narrow in on the answer, such as at what stage this filtering is taking place as you've alluded, why don't you share it?
The answer is simple. Unintended subsonic content (i.e., noise, rumble) eats amplifier power and expends cone excursion to no useful purpose. It is good engineering practice to remove it. It can be removed at different points in the chain: the mic preamp, the predub sessions using a DAW (workstation), or in post production using a DFC (console).
Edited by Roger Dressler - 11/17/12 at 4:06pm
post #42 of 105
Quote:
Originally Posted by pitviper33 View Post

The content on many discs is HPFed.
Besides 'Master & Commander', which seems to have been HPFed in error, which other discs are high pass filtered?
post #43 of 105
Quote:
Originally Posted by Roger Dressler View Post

Here is the entirety of the OP's original question: >>Why do some movies on DVD/Blu-ray Disc have the bass filtered? Is it to "protect" home theaters?<< Notice the specific mention of protecting home theaters? Notice he did not ask why soundtracks in movie theaters have the bass filtered? It seems pretty clear that he was asking why content heading home gets the bass filtered.
I see two questions there. The first is why content is filtered. The second is a proposed answer from him, formed as another question. I don't see that the second question has to limit the scope of the first. You read it one way; I read it another. Regardless, if we continue to argue the semantics of the question we'll just run around in circles and nobody learns anything. I vote we let the question that started all this be done at this point.
Quote:
Originally Posted by Roger Dressler View Post

We all know about one famous example, M&C. Is he asking why it ever happened like in M&C? That one was investigated (I was one of the folks who did such investigation, and posted my findings).
Happen to remember where you posted that info? I've read a thread or two about it, but I don't know if I ever saw a nice conclusion.
Quote:
Originally Posted by Roger Dressler View Post

If you are asserting many soundtracks are being filtered for home use, then please cite the evidence. If you are asserting that many movie soundtracks as released to theaters have HP filtering, that is a different matter altogether.
I'm merely noting that the content on the disc is filtered. I've made no assertion about where or why that filtering took place. Where and why that filtering took place is exactly the question.
Quote:
Originally Posted by Roger Dressler View Post

The answer is simple. Unintended subsonic content (i.e., noise, rumble) eats amplifier power and expends cone excursion to no useful purpose. It is good engineering practice to remove it. It can be remove at different points in the chain: the mic preamp, the predub sessions using a DAW (workstation), or in post production using a DFC (console).
Okay, it makes perfect sense why unintended infrasonic content should be removed. But why was unintended infrasonic content there in the first place? Depending of course on the recording environment, shouldn't noise unrelated to the scene (infrasonic or otherwise) be pretty minimal? Applying a blanket HPF to everything seems a bit like throwing out the baby with the bath water doesn't it? The impact (no pun intended) of infrasonic cues to the realism of the playback experience is quite obvious. I can't believe that those creating the recordings or mixes at any stage are unaware of it.
post #44 of 105
Quote:
Originally Posted by sdurani View Post

Quote:
Originally Posted by pitviper33 View Post

The content on many discs is HPFed.
Besides 'Master & Commander', which seems to have been HPFed in error, which other discs are high pass filtered?



Do you have any restrictions on the movie release date in mind? If not, there are a gazillion movies that would appear to be HP filtered.
post #45 of 105
Quote:
Originally Posted by pitviper33 View Post

Quote:
Originally Posted by Roger Dressler View Post

Here is the entirety of the OP's original question: >>Why do some movies on DVD/Blu-ray Disc have the bass filtered? Is it to "protect" home theaters?<< Notice the specific mention of protecting home theaters? Notice he did not ask why soundtracks in movie theaters have the bass filtered? It seems pretty clear that he was asking why content heading home gets the bass filtered.
I see two questions there. The first is why content is filtered. The second is a proposed answer from him, formed as another question. I don't see that the second question has to limit the scope of the first. You read it one way; I read it another. Regardless, if we continue to argue the semantics of the question we'll just run around in circles and nobody learns anything. I vote we let the question that started all this be done at this point.
Quote:
Originally Posted by Roger Dressler View Post

The answer is simple. Unintended subsonic content (i.e., noise, rumble) eats amplifier power and expends cone excursion to no useful purpose. It is good engineering practice to remove it. It can be remove at different points in the chain: the mic preamp, the predub sessions using a DAW (workstation), or in post production using a DFC (console).
Okay, it makes perfect sense why unintended infrasonic content should be removed. But why was unintended infrasonic content there in the first place? Depending of course on the recording environment, shouldn't noise unrelated to the scene (infrasonic or otherwise) be pretty minimal? Applying a blanket HPF to everything seems a bit like throwing out the baby with the bath water doesn't it? The impact (no pun intended) of infrasonic cues to the realism of the playback experience is quite obvious. I can't believe that those creating the recordings or mixes at any stage are unaware of it.



Read postings made by Filmmixer near the link below. The link is in the middle of the discussion about sub 20 Hz content.

QUOTE:

"And practically speaking, what if we could reproduce content down to 8-12Hz?

Should I filter it knowing it won't play anywhere else?

If I let it go, I know, based on experience, that I will over compensate the LFE down, and it will be anemic on 99% of the systems it plays back on...... and all that information takes up a lot if headroom (which is one of the reasons filtering isn't always a bad idea...)"


http://www.avsforum.com/t/1333462/the-new-master-list-of-bass-in-movies-with-frequency-charts/3510#post_21995228
post #46 of 105
Quote:
Originally Posted by pitviper33 View Post

I see two questions there. The first is why content is filtered. The second is a proposed answer from him, formed as another question.
See the ""it" in the second sentence? It refers to the first sentence. It is not a new question.
Quote:
I vote we let the question that started all this be done at this point.
Fine with me. You are the one who stepped in whist I was awaiting to hear back from the OP. No progress can be made on the OP's question until he clarifies it. That is exactly where we started.
Quote:
Happen to remember where you posted that info? I've read a thread or two about it, but I don't know if I ever saw a nice conclusion.
See this post and this one.
Quote:
Okay, it makes perfect sense why unintended infrasonic content should be removed. But why was unintended infrasonic content there in the first place?
Because mics have better hearing than people. They pick up stuff we do not notice.
Quote:
Depending of course on the recording environment, shouldn't noise unrelated to the scene (infrasonic or otherwise) be pretty minimal?
People have gotten sick working in an office where the AC units shook the ceiling <10 Hz but no one knew why until spectral analysis was conducted. That same noise shows up in production sound.
Quote:
Applying a blanket HPF to everything seems a bit like throwing out the baby with the bath water doesn't it?
Aside from M&C, who said a blanket HPF is applied?
Quote:
The impact (no pun intended) of infrasonic cues to the realism of the playback experience is quite obvious. I can't believe that those creating the recordings or mixes at any stage are unaware of it.
It depends on what constitutes cues and realism. Can you give an example where infrasonics made an obvious difference in realism?

I do not find most movie theaters using gear that can reproduce infrasonic bass. Most movie soundtracks are fabricated, not to document reality, but to create a convincing illusion when reality cannot be depicted.
Edited by Roger Dressler - 11/17/12 at 4:42pm
post #47 of 105
Quote:
Originally Posted by J_Palmer_Cass View Post

Read postings made by Filmmixer near the link below. The link is in the middle of the discussion about sub 20 Hz content.
QUOTE:
"And practically speaking, what if we could reproduce content down to 8-12Hz?
Should I filter it knowing it won't play anywhere else?
If I let it go, I know, based on experience, that I will over compensate the LFE down, and it will be anemic on 99% of the systems it plays back on...... and all that information takes up a lot if headroom (which is one of the reasons filtering isn't always a bad idea...)"
http://www.avsforum.com/t/1333462/the-new-master-list-of-bass-in-movies-with-frequency-charts/3510#post_21995228

Interesting idea there. I hadn't been thinking how if a significant portion of LFE energy is ULF, that soundtrack might come across as thin on systems that fail to reproduce it. That makes a lot of sense, and I don't see any easy was around it.

I'll read through some of the discussion in the movies with bass thread in the area you recommended. That thread is all over the place and tremendously long, so I haven't read most of it.
post #48 of 105
Quote:
Originally Posted by Roger Dressler View Post

Because mics have better hearing than people. They pick up stuff we do not notice.
People have gotten sick working in an office where the AC units shook the ceiling <10 Hz but no one knew why until spectral analysis was conducted. That same noise shows up in production sound.
I won't claim to have any familiarity with the tools being used here, but shouldn't this kind of stuff be pretty easy to detect during mixing? And then couldn't the mixer tell whether it was intended or unintended content?

Quote:
Originally Posted by Roger Dressler View Post

Aside from M&C, who said a blanket HPF is applied?
Actually I kind of thought you did:
Quote:
Originally Posted by Roger Dressler View Post

Unintended subsonic content (i.e., noise, rumble) eats amplifier power and expends cone excursion to no useful purpose. It is good engineering practice to remove it. It can be removed at different points in the chain: the mic preamp, the predub sessions using a DAW (workstation), or in post production using a DFC (console).
Maybe I misunderstood.

Quote:
Originally Posted by Roger Dressler View Post

It depends on what constitutes cues and realism. Can you give an example where infrasonics made an obvious difference in realism?
When haven't they? This is surely up to interpretation, but I've found all of the well known scenes with substantial infrasonic content in the right places to be more engaging than similar scenes without. Hardly scientific, but I find it to be a very convincing effect. The example we've already discussed, M&C, is pretty easy to compare. I shared my own feelings on the difference with and without for that example earlier in the thread. I've tried applying a 20Hz HPF on other famous scenes like War of the World (pod emergence) and How to Train Your Dragon (final dragon fight), and I found my own envelopment noticeably reduced. That's a terrible test setup, but it's all I've got. To me it's an obvious difference. We're all familiar with the more famous ULF scenes. I must not be the only one that finds the effect to be an enhancement.
post #49 of 105
Quote:
Originally Posted by pitviper33 View Post

I won't claim to have any familiarity with the tools being used here, but shouldn't this kind of stuff be pretty easy to detect during mixing? And then couldn't the mixer tell whether it was intended or unintended content?
Ok. Let's say it is easily detected and decided it was unintended. So they'd filter it, no?
Quote:
Actually I kind of thought you did: Maybe I misunderstood.
I did not intend that.
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When haven't they?
It's your assertion. The burden is on you to bring evidence.
Quote:
This is surely up to interpretation, but I've found all of the well known scenes with substantial infrasonic content in the right places to be more engaging than similar scenes without. Hardly scientific, but I find it to be a very convincing effect. The example we've already discussed, M&C, is pretty easy to compare.
Unfortunately, the M&C BD filtered not only infrasonic bass but regular old audible bass, too. My plot shows the equivalent of an 8th-order 27 Hz HPF.

This points out a problem: the term infrasonic is used loosely. Subs for homes and cars often have "infrasonic" filters at 30 Hz. I think to be safe we want to make sure our discussion here excludes the idea of attenuating frequencies down to 20 Hz. That means any practical filter's cutoff would have to be well below that. For example, a typical 20 Hz 4th order Linkwitz-Riley filter is down 6 dB at 20 Hz due to the way it is aligned for crossover purposes. That filter can be audible even on content that has nothing present below 20 Hz.
Quote:
I shared my own feelings on the difference with and without for that example earlier in the thread. I've tried applying a 20Hz HPF on other famous scenes like War of the World (pod emergence) and How to Train Your Dragon (final dragon fight), and I found my own envelopment noticeably reduced.
What are the electrical characteristics of that filter? It, too, may be rolling off more than just infrasonic frequencies, as mentioned above.
post #50 of 105
Quote:
Originally Posted by pitviper33 View Post

Quote:
Originally Posted by Roger Dressler View Post

Which discs were filtered, and how do you know?
Surely the most famous example is the Master and Commander blu-ray. You can tell quite easily by listening to the first battle scene on the DVD for comparison. It's a HUGE difference. I own both discs. The DVD makes an excellent demo disc (for audio). It's one of the most engaging action scenes I've ever experienced in a movie. You FEEL each cannon blast. The same scene on the blu-ray is bland and uninvolving. It feels like just another battle sequence. Despite the dramatic improvement in picture quality, the neutered blu-ray has near zero replay value. I'll reach for the DVD every time.

Listening tests of recording can be highly misleading. because they rely on the quality of the listener's system and his preferences.

If you really want to know about a recording's LF content you rely on analytical tools such as digtial editors and FFT analysis.

Here's an example:

One recording has smooth, extended bass response and the other has the response peaked up at say 40 Hz and sharply rolled off below that.

The peaked up recording may be more involving and will shake your guts on 90% of all home audio systems and virtually every theater system because those systems lack strong response below 30 Hz.

Play the recording with flat response on a system with strong response below 30 Hz, and going down to 10 Hz and it may be a listening experience beyond compare, while it may still sound bland and uninvolving on most people's systems.

Very few people seem to actually know what the measured low bass response of their systems actually are. Systems with strong clean response below 20 Hz are like hen's teeth.

I am familiar with $5,000 subwoofers from manufacturers that should know better, than can't cut this kind of mustard. OTOH a few of the right (> 30 mm Xmax) 13-18" subwoofer drivers ducted in from your basement can be excellent, physically move you, and cost only a fraction as much.
post #51 of 105
Quote:
Originally Posted by Roger Dressler View Post

Ok. Let's say it is easily detected and decided it was unintended. So they'd filter it, no?
Obviously. Where exactly are we going with this?

Quote:
Originally Posted by Roger Dressler View Post

It's your assertion. The burden is on you to bring evidence.
I'm being asked to show evidence that infrasonic content is noticeable? I just want to make sure I'm getting that right.
post #52 of 105
Quote:
Originally Posted by Roger Dressler View Post

Quote:
Originally Posted by pitviper33 View Post


The M&C BD filtered not only infrasonic bass but regular old audible bass, too. My plot shows the equivalent of an 8th-order 27 Hz HPF.

That seems like a reasonable choice to me. A filter like that leaves plenty of gut-shaking and window rattling signals in place, but avoids problems with most home and theater systems.

It ain't real high fidelity but it avoids problems with 90% of the audio systems out there.

Also, LFE tracks are a zero-sum game. Any energy you add below 27 Hz subtracts from how much there can be above 27 Hz.
Quote:
This points out a problem: the term infrasonic is used loosely. Subs for homes and cars often have "infrasonic" filters at 30 Hz.

If that low. Theaters too.

Pinch yourself. It is very common for broad-line speaker manufacturers to include odd little gizmos like "subwoofers" with a single 6 1/2 driver.

Please tell me I'm imagining this:

http://www.polkaudio.com/products/pswi8m

;-)
Quote:
I think to be safe we want to make sure our discussion here excludes the idea of attenuating frequencies down to 20 Hz. That means any practical filter's cutoff would have to be well below that. For example, a typical 20 Hz 4th order Linkwitz-Riley filter is down 6 dB at 20 Hz due to the way it is aligned for crossover purposes. That filter can be audible even on content that has nothing present below 20 Hz.

Just barely if the speaker is clean. If the speaker is not clean that filter can be very audible due to the trouble that it keeps the driver out of.
Quote:
Quote:
I shared my own feelings on the difference with and without for that example earlier in the thread. I've tried applying a 20Hz HPF on other famous scenes like War of the World (pod emergence) and How to Train Your Dragon (final dragon fight), and I found my own envelopment noticeably reduced.
What are the electrical characteristics of that filter? It, too, may be rolling off more than just infrasonic frequencies, as mentioned above.

I'll take the devil's advocate position here and argue that your evaluation, besides its exposure to your own personal bias, isn't about giving the contrary view all of the chances that nature can give it. If you filter out signal below a certain frequency you pick up headroom that you could invest in peaked-up response just above the filter corner frequency. There is no doubt that 30 Hz is far more audible and in its way enveloping than 15 Hz.

I say this as a person who is intimately familiar with and highly appreciative of subs wtth strong clean response down to 10 Hz. There is no doubt that with the right recording they are experiences. The phrase "listen to" fails! ;-)

But now we are talking about a product that we are selling to the mass market.
post #53 of 105
Thread Starter 
Okay, I am getting a little confused. tongue.gif

I knew that some movies, while it may be rare, had some of the bass filtered out. When you say that the bass was filtered out, does that mean the ULF or even some of the 30 Hz and above bass? My question was to know why this happens. Why do they filter out the bass? When they filter out the bass, does that mean that when the movie is played in a movie theater, you get the "whole" soundtrack including all the bass and when it hits home video, the bass is "cut out?"
post #54 of 105
Quote:
Originally Posted by Kain View Post

When they filter out the bass, does that mean that when the movie is played in a movie theater, you get the "whole" soundtrack including all the bass and when it hits home video, the bass is "cut out?"

I'm not aware of any cases like that. My experience is quite the opposite for many movies. I've heard much cleaner and deeper extended bass at home than at movie theaters. Now is that because the theater is failing to reproduce content that's there? Or is it because the very low frequency content that made it to the disc didn't make it to the theater source? I don't know.
post #55 of 105
Quote:
Originally Posted by pitviper33 View Post

Obviously. Where exactly are we going with this?

I'm being asked to show evidence that infrasonic content is noticeable? I just want to make sure I'm getting that right.
My question was >>Can you give an example where infrasonics made an obvious difference in realism?<< And you replied: >>When haven't they?<< This suggests there are abundant examples. But as Arny points out, it is not easy to make that determination. The two tests you described, comparing M&C versions, and switching on/off some sort of 20 Hz HPF, are not conclusive.
post #56 of 105
Quote:
Originally Posted by arnyk View Post

Quote:
Originally Posted by Roger Dressler View Post

Quote:
Originally Posted by pitviper33 View Post


The M&C BD filtered not only infrasonic bass but regular old audible bass, too. My plot shows the equivalent of an 8th-order 27 Hz HPF.

That seems like a reasonable choice to me. A filter like that leaves plenty of gut-shaking and window rattling signals in place, but avoids problems with most home and theater systems.

It ain't real high fidelity but it avoids problems with 90% of the audio systems out there.


What problem does infrasonic content have on 90% of the audio systems out there? None that I know of (assuming you are talking consumer based systems).

The DIY crowd may have problems because they tend to use high powered amplifiers without the use of HP filters and limiters in order to protect their speakers.
post #57 of 105
Quote:
Originally Posted by pitviper33 View Post

Quote:
Originally Posted by J_Palmer_Cass View Post

Read postings made by Filmmixer near the link below. The link is in the middle of the discussion about sub 20 Hz content.
QUOTE:
"And practically speaking, what if we could reproduce content down to 8-12Hz?
Should I filter it knowing it won't play anywhere else?
If I let it go, I know, based on experience, that I will over compensate the LFE down, and it will be anemic on 99% of the systems it plays back on...... and all that information takes up a lot if headroom (which is one of the reasons filtering isn't always a bad idea...)"
http://www.avsforum.com/t/1333462/the-new-master-list-of-bass-in-movies-with-frequency-charts/3510#post_21995228

Interesting idea there. I hadn't been thinking how if a significant portion of LFE energy is ULF, that soundtrack might come across as thin on systems that fail to reproduce it. That makes a lot of sense, and I don't see any easy was around it.

I'll read through some of the discussion in the movies with bass thread in the area you recommended. That thread is all over the place and tremendously long, so I haven't read most of it.



Start reading about 1 page before the page shown in my link to give some context to that mixing topic.

"We all follow the industry standard spec which sharply drops off at 20Hz on the sub channel..

We aren't hearing all the ULF stuff you guys are talking about.. and it's why I've said in the past that if you suspect stuff is down there, as a mixer, you either filter it if you're concerned about it translating down the line, or leave it in for later, knowing that some HT's go that low...

As I've said in the past, you guys are monitoring stuff which wasn't heard on a dub stage because we have subs that are tuned to a standard which most on this thread are not following.

Our ELF LCR systems do go into the teens (and have no filters on them.....).. but almost all theaters are only good to ~30Hz in the LCR using 2x or 4x 15" drivers."


http://www.avsforum.com/t/1333462/the-new-master-list-of-bass-in-movies-with-frequency-charts/3480#post_21990880



Also, take a look at the FR chart of the room that FilmMixer uses. Infrasonic content is not monitored for the most part as it is not part of the standard movie reference.



post #58 of 105
Quote:
Originally Posted by arnyk View Post

I'll take the devil's advocate position here and argue that your evaluation, besides its exposure to your own personal bias, isn't about giving the contrary view all of the chances that nature can give it. If you filter out signal below a certain frequency you pick up headroom that you could invest in peaked-up response just above the filter corner frequency. There is no doubt that 30 Hz is far more audible and in its way enveloping than 15 Hz.
I say this as a person who is intimately familiar with and highly appreciative of subs wtth strong clean response down to 10 Hz. There is no doubt that with the right recording they are experiences. The phrase "listen to" fails! ;-)
But now we are talking about a product that we are selling to the mass market.
Hi Arny. Not sure how this happens, but even though you wrote the above text, the way it appears in your post makes it look like I wrote it.

And the quotes I wrote now appear as from Pitviper.

Might try a different editing method to avoid confusion.
post #59 of 105
JPC: There's some really great discussion smack dab in the middle of that monster thread. Thanks for pointing me to it.

The summary of what I read, as I interpreted it, is that the industry is largely unconcerned with what's going on down in the infrasonic region. Other than a few exceptions, they're not motivated to change. The systems they're using to evaluate their product are incapable of reproducing that content. Those of us that believe infrasonic content adds significantly to the viewing experience are too small a minority to even be on their radar screens.
post #60 of 105
Thread Starter 
Another question popped up in my head in regards to these two formats. Where do we go from here? I mean they are both already lossless so how do we improve the sound in the future? By adding more channels?
Edited by Kain - 11/29/12 at 7:04am
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