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Wow houses must vary considerably: with an 18 and two 12's in the HT I can easily hear a 50 cal machine gun outside or at the front door when I watched the Big Red One; I figured someone would think it was the real thing if they walked by! lol!!!
Our windows don't rattle annoyingly, nor have I had any 'walking' objects. It's not too noticeable past the front curb, maybe 20ft from the front door; I don't want to listen at higher volumes than that anyway. The entire house thunders though!
 

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I live in an apartment and have done this with my neighbours and don't see how it is passive aggressive. I also asked that if it became an issue, to let me know 'when' so we could work out what I was watching, how loud etc and if it were at an odd time so I could maximise my fun at minimum inconvenience to them. So far zero complaints, but I tend to crank it at reasonable times and watch dialogue driven flicks at less friendly times like late at night.

Movies I also find are less of an issue than modern music with a regular beat. Doof, doof is more annoying to many than a couple of minutes of not readily identifiable loud noise from a movie which is not consistent or predictable.

I'm still going to add more soundproofing as I work on the room acoustics as I would like even less potential for neighbour disturbance and for me to play louder at times.

Solid walls and acreage would be nice but lotto-win dream for many of us unfortunately.
Yeah, maybe "passive aggressive" was the wrong language to indite; What I meant was that the more subtle hints regarding your inclination to be a good neighbor that you can express to the surrounding community, the more leniency you will be given towards playing movies at higher volume levels now and then as a direct result. If only everyone knew how far a smile would take them, I should think there would be a lot more smiling in the world today (even if for purely selfish reasons :huh: )

As for a house on 10 acres.. It sure seemed like a pipe dream to me 2 months ago as well, but simply asking a family friend/realtor if I had a chance at home ownership turned out to be one of the best decisions I've ever made, because I was pleasantly surprised to learn that even owning a home, period, was possible for me now. If you have a steady job, look into buying- you might just be as surprised as I was!
Being that my neighbors are hard to track down i had conciderd putting a sign out in the front yard telling them that if it's too loud just let me know instead of calling the police. But that would just invite thieves, allthough with too ''monster dogs'' in the house i really don't think any uninvited guests would enter.

My solution to the problem has been to keep the volume at a recpectable level, i've got 13 month old twins now anyways so turning the volume up isn't really an option anymore. Problem solved.:clap:
Lol, turn it down and problem solved! That's a good point on inadvertantly letting the world know you have expensive gear inside as well.. I'm not used to having anything worth stealing, so this is taking some getting used to haha
 

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Yeah like i said also, i don't think any uninvited guest will attempt to come in do to my ''security dogs''. Also i've relized that when the kids are at grandma and grandpas as long as it's the right time of day it's ok to rock out a bit but advertising your awesome setup to the world isn't really the best idea anyhow.
 

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As for a house on 10 acres.. It sure seemed like a pipe dream to me 2 months ago as well, but simply asking a family friend/realtor if I had a chance at home ownership turned out to be one of the best decisions I've ever made, because I was pleasantly surprised to learn that even owning a home, period, was possible for me now. If you have a steady job, look into buying- you might just be as surprised as I was!
Totally agree.
plus, IMHO:

paying rent means your money goes away
paying mortgage means your money is here to stay
 

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As for a house on 10 acres.. It sure seemed like a pipe dream to me 2 months ago as well, but simply asking a family friend/realtor if I had a chance at home ownership turned out to be one of the best decisions I've ever made, because I was pleasantly surprised to learn that even owning a home, period, was possible for me now. If you have a steady job, look into buying- you might just be as surprised as I was!

I just recently bought my first house. With the low interest rates, I'm paying $225 more per month for my single family detached house. For me, it was totally worth it to not have to share walls. Ahhhh... I can finally play my games & movies as loud as I want. And I can turn my subwoofer up past 2. It goes to 10. :D
 

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Reference level is when you have An XPA-1 hooked up to each of your towers and you start to smell magic smoke.:whistling: Oh, wait, that would be beyond reference level.:yikes:
 

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85db is actually reference level, and in order to have a reference capable system, you need 20db dynamic headroom from each channel. 75db is what some discs or receivers have you calibrate to using their test tones simply because 10db less is easier to withstand during calibration. The LFE channel is 10db louder, so reference is 95db with the need to be able to handle 115db.

So to sum it up, if you are designing new speakers, the capability you need is for them to reach 105db across their intended range at your seat and the subwoofer 115db. If you cross the speakers over at 80hz, then the subwoofer system actually needs to be able to do ~118db.
What do you mean by "20 dB dynamic headroom"? How does one calculate and/or measure the available dynamic headroom?
 

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What do you mean by "20 dB dynamic headroom"? How does one calculate and/or measure the available dynamic headroom?
You use the onlline SPL calculator (google it) and see if your amplifier can drive your mains to 105 db at the listening position, and you can find out if your sub can do 115 db AT 20HZin various ways.

However that doesn't factor in thermal compression. Even if your amp can drive your speakers to 105db, your speakers may lose their compusre at those peaks.

Most people's systems can't do reference levels properly. Regular tweeters just don't have the thermal power handling to do so. You usually need some sort of waveguide or horn loading for the tweeter, or a non-conventional multi-tweeter speaker design like the RBH T2 system. My tweeters for example actually have limiting in which they can't sustain anything above 103 db before the protection kicks in. They can do a dynamic transient higher, but not sustained. I've never heard my speakers compress, but then I don't own a pair of JTR Triple 8s to reference them against either.

Professional audio speakers are much more capable of the dynamic range which we associate with movie reference levels.
 

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The SPL calculator does not address "dynamic headroom". It actually disclaims dynamic headroom in the text. Quote: "This calculator does not account for room acoustics, amplifier dynamic headroom or off axis listening positions." If you are really expecting 20 dB of crest factor in your program material, you will need a 10 kW amplifier for a typical home theater. Of course no HT speaker can withstand 10 kW, even on a program peak. I think the old rule of 10-13 dB of headroom is more realistic of program material. Remember we are already considering the loudest passage that the sound system will encounter.
 

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The SPL calculator does not address "dynamic headroom". It actually disclaims dynamic headroom in the text. Quote: "This calculator does not account for room acoustics, amplifier dynamic headroom or off axis listening positions."
Dynamic amplifier power is nothing more than marketing rubbish.

If you are really expecting 20 dB of crest factor in your program material, you will need a 10 kW amplifier for a typical home theater. Of course no HT speaker can withstand 10 kW, even on a program peak. I think the old rule of 10-13 dB of headroom is more realistic of program material. Remember we are already considering the loudest passage that the sound system will encounter.
10kW, really? For an 88dB speaker on it's own at 4m with 800W you get THX ref level at the LP of 105dB. As I presume it is 2 or 4 pi space and not a room where the reverberant sound will also add to the apparent level, and the recommendation from Toole (IIRC, not in front of me ATM) is 3dB not 6dB loss per doubling of distance, then we're back to 400W. High, but not unrealistic.

Now get some sensible speakers with decent efficiency and volume displacement and reference at the LP is easy.

Dialogue is supposed to be mastered at the 75-85dB level and with peak loudness at 105dB, a 20dB+ crest factor is not unrealistic. Just make sure you have enough speaker and amp to do it.

Calculator used is from here. [first google hit]
 

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Dynamic amplifier power is nothing more than marketing rubbish.

10kW, really? For an 88dB speaker on it's own at 4m with 800W you get THX ref level at the LP of 105dB. As I presume it is 2 or 4 pi space and not a room where the reverberant sound will also add to the apparent level, and the recommendation from Toole (IIRC, not in front of me ATM) is 3dB not 6dB loss per doubling of distance, then we're back to 400W. High, but not unrealistic.

Now get some sensible speakers with decent efficiency and volume displacement and reference at the LP is easy.

Dialogue is supposed to be mastered at the 75-85dB level and with peak loudness at 105dB, a 20dB+ crest factor is not unrealistic. Just make sure you have enough speaker and amp to do it.

Calculator used is from here. [first google hit]
No, actually not 10 kW. According to your example, you need 20 kW. The problem comes down to what we mean by "Watts".

The first mistake in all the calculators is that there is no such thing as "Watts RMS" in these calculations. The simplest, arithmetic form of the equation is Volts, RMS X Amps, RMS = Watts, average. So now we know that we are taking an average power.

The second problem is the speaker sensitivity measurement. As I understand it, the sensitivity measurement is taken driving the loudspeaker with a sine wave. Beginning with that, and working through the calculator with your example, we get 105 dB SPL with 800 W average. But that would be a scaled version of the speaker sensitivity measurement at 105 dB instead of 88 dB. That is not home theater. My question in all this is how to relate this to home theater, which I presume is employing movie soundtracks, and not sine waves.

I believe this all comes down to the "dynamic headroom" which is allowing for the difference between average and peak power in the program content. In the speaker sensitivity test, using sine waves, the peak power in the speaker is 2X the average power. This happens because the sine wave applied to the speaker has a peak voltage that is the square root of 2 higher than the RMS value of the waveform. Since power is proportional to the square of the applied voltage, at the peak of the waveform the instantaneous power is twice the average power. This, BTW, is the genesis of "peak power ratings", which are not rubbish. As we say, figures don't lie, but liars figure. Peak power is often presented to be the same thing as average, which it isn't, and that part is the marketing rubbish. But I digress.

As we all know, 2X the power is 3 dB. So your amplifier needs 3 dB of "dynamic headroom", just to reproduce a sine wave. However, this headroom is already included in the amplifier's power spec, so we don't add it in twice. So what dynamic headroom should we be allowing for when we wish to reproduce movie soundtracks?

Some years ago, this problem was faced by broadcasters who had the same problem trying to broadcast program material without over modulating. A noise signal was developed, based on work done characterizing radio program material. This noise signal became known as USASI noise and a standard containing the definition of this noise source is given here: http://www.nrscstandards.org/SG/NRSC-1-A.pdf

Page 17 of this standard shows this noise spectrum. Note that it rolls off at 6 dB/octave on both sides of the peak at about 200 Hz. A study of the peak-average ratio, or crest factor of USASI noise reveals that it is 10 dB. This means that to reproduce 88 dB of USASI noise requires 10 dB of dynamic headroom, or 10X amplifier power to reproduce the random peaks of the signal. In other words, you can run the 88 dB speaker sensitivity test with a 1 W amplifier, but if you used USASI noise you would need a 10 W amplifier to produce 88 dB on your SPL meter.

Going through the SPL calculator with your example, and listening at 105 dB, you need 8 kW of amplifier power, or if you use the -3 dB/double distance rule for a reverberant room instead of the -6 dB rule for free-field conditions, it requires 2 kW. (You quadrupled the distance to 4 m so you saved 6 dB of amp power.)

Now, in your example, you were quoting a 20 dB crest factor. I only subscribe to 10 dB, which I have justified above. However, the broadcast industry's program material model may be too compressed for the movie industry, and 20 dB may be closer to the truth. If that were true, then add another 10X to amplifier, and get 20 kW required power.
 

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Since nobody has really address this question, I will. Reference level is not 75db or 85db. It is actually 0 digital reference, or the loudest digital signal before system overload. So reference levels for the cinema would be 105db for each main channel, and 115db for the LFE based on 0 reference. This would be continuous output, and nobody can really stand this kind of output continuously.
 

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Since nobody has really address this question, I will. Reference level is not 75db or 85db. It is actually 0 digital reference, or the loudest digital signal before system overload. So reference levels for the cinema would be 105db for each main channel, and 115db for the LFE based on 0 reference. This would be continuous output, and nobody can really stand this kind of output continuously.
Does this mean it's impossible for a signal to ever peak above these?
 

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Does this mean it's impossible for a signal to ever peak above these?
Yes the signal can peak above 0db, however it is pure distortion at that point. It is truly not something you want to hear.
 

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your question to me is very broad.... you speak of what is reference, do you mean reference level speakers? reference level processors? reference level amplifiers? maybe your looking for mid-fi equipment which is still very expensive but not in the 100k level? mid-fi is generally 18-28k+ for a theater system approximately.. first if you say that this is the last system you want to buy you need to define a budget, before you go any further.

just my .02

thomaswmaz
 

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your question to me is very broad.... you speak of what is reference, do you mean reference level speakers? reference level processors? reference level amplifiers? maybe your looking for mid-fi equipment which is still very expensive but not in the 100k level? mid-fi is generally 18-28k+ for a theater system approximately.. first if you say that this is the last system you want to buy you need to define a budget, before you go any further.

just my .02
I think you're totally lost my friend. This thread is discussing the strict definition of "reference level" sound pressure levels IE the sort defiined by Dolby or THX or whomever.
 

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I just recently bought my first house. With the low interest rates, I'm paying $225 more per month for my single family detached house.
Congrats on your first home. The hard work pays off. And now the sweet joy of ownership - playing music to your "reference level.":T

I can't even rent a room for $225 around here.:D So envious!
 

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I have little problem in reaching reference levels as I have Klipsch RF-82s for mains and my 5 speakers are driven by a new 80lb Outlaw 7500 power amp and my subwoofer is the 160lb SVS PB13 Ultra (with Sledge amp). Watching War of the Worlds proved to be profound. I metered the system at 116.5 db with both the power amp and sub driving that sound pressure level effortlessly. For your interest, the scene where the pods blow up the bridge behind Ray's (Cruise) house is the loudest in the movie.

SPSs at 90db is more then good for me for 2 hours while 82db-85db is a comfortable continously LOUD listening level.

Thanks for everybody's analysis. You guys definitely know a lot more than me.
 

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Had a good summer storm here today, lots of thunder and lightning so I put TRON on and cranked it up to eleven and threw away the knob.
That movie is AWESOME at reference levels. I judge my reference level the same way as we did it when I worked at the local twin cinema, the dialogue should be clearly audible and let a couple of Kw of amps and LOTS of subs take care of the rest.
A soundtrack with good dynamic range like TRON is a great indicator.
Trouble is you can only play it during the day, the sound would carry blocks away during the night!!!
I use two active 15" vented subs via FBD plus twin 12" sealed just to augment the centre channel.
-Plus a bunch of amps from the receiver pre-outs.
Add a 6meter screen and Bob's your uncle!!
 

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Had a good summer storm here today, lots of thunder and lightning so I put TRON on and cranked it up to eleven and threw away the knob.
That movie is AWESOME at reference levels. I judge my reference level the same way as we did it when I worked at the local twin cinema, the dialogue should be clearly audible and let a couple of Kw of amps and LOTS of subs take care of the rest.
A soundtrack with good dynamic range like TRON is a great indicator.
Trouble is you can only play it during the day, the sound would carry blocks away during the night!!!
I use two active 15" vented subs via FBD plus twin 12" sealed just to augment the centre channel.
-Plus a bunch of amps from the receiver pre-outs.
Add a 6meter screen and Bob's your uncle!!

This is arguably the best explanation of FUN in one's system that I ever read. That is movie watching.

My two favourite lines are...

Cranking it up to eleven and throwing away the knob.
Add a 6 meter screen and Bob's your uncle.


That's the way it's done and bollocks to the neighbours. :hsd:
 
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