Sound deadening doors!
05-29-2004, 03:13 PM
#71
50 Watt CAFz'r
Join Date: Mar 2004
Posts: 146
Originally posted by Mr. Marco:
Only today did i run both the front end and the W7 simultaneously. It sounds so damn sweet! the W7 adds that extra low extension and completes the sound spectrum. i however think i have a peak at around 60-80 hz. i'd love to have it measured.
the eights are definetly impressive, and currently its te best they've ever sounded. I almost feel as if i can run this two way without adding a sub. Nonetheless, the W7 is working wonderously, as JL states, it sounds, for lack of a better word, TIGHT! by far the best sub i've ever played with. i'm just dying to get the revelators in there. YUM!
Only today did i run both the front end and the W7 simultaneously. It sounds so damn sweet! the W7 adds that extra low extension and completes the sound spectrum. i however think i have a peak at around 60-80 hz. i'd love to have it measured.
the eights are definetly impressive, and currently its te best they've ever sounded. I almost feel as if i can run this two way without adding a sub. Nonetheless, the W7 is working wonderously, as JL states, it sounds, for lack of a better word, TIGHT! by far the best sub i've ever played with. i'm just dying to get the revelators in there. YUM!
I'm hoping it will perform pretty good in the 80-150HZ range also.
05-30-2004, 06:56 PM
#73
50 Watt CAFz'r
Join Date: Mar 2004
Posts: 146
Originally posted by Mr. Marco:
Halo2,
yes, yes, and go ahead and get one.
however why would you need it to play up that high?
the boys at JL told me to cap it at 80 hz... then again its all about application...
what's yours?
Halo2,
yes, yes, and go ahead and get one.
however why would you need it to play up that high?
the boys at JL told me to cap it at 80 hz... then again its all about application...
what's yours?
06-06-2004, 04:43 PM
#76
50 Watt CAFz'r
Join Date: Mar 2004
Posts: 146
what's your front end?
06-06-2004, 07:01 PM
#77
if the volume is loud enough, i can imagine that it would be hard to differentiate where the bass is coming from. however, if the volume is at normal listening level, i think (at leas in my own personal experience), it will be pulled back. if you must cross it that high, do it with as high a slope as possible. i'd recommend at least 18 db/octave. i don;t think the slope would have any effect on SQ... but would anyone care to comment on that?
06-06-2004, 08:30 PM
#78
1000 Watt CAFz'r
Thread Starter
Join Date: Oct 2003
Posts: 1,783
^^Yes, I can comment on that.
People actually have 3 ears.
Say what?
People probably think I'm nuts but I will explain. Your skull acts as your 3rd ear, it sends mono signals to your brain from abient energy in the air. Then your brain takes takes the information from your ears and compares it to the mono signal to derive directional information. This is why wearing something over your skull like a toque decreases spatial awareness. This is also partly why humans become disoriented when high SPL is present. Thus the dizzy feeling with TONS of bass, kind of a natural but damaging high. Higher frequency information naturally has less energy in it, thus it shakes your skull less. This reduces the saturation of energy that overwhelms the directional information from your ears. In short, the higher the frequency, the more sensitive your ears are to location.
My personal experience with moderate level sound in car has led me to believe that frequencies above 50 or 60 hz can easily have their source located. I've further found that chosing as steep a slope as possible for rear mounted subs helps to hide their location. I've tried everything from 12db/oct to 36db/oct. with my subs, and the steeper always seemed to be more musical to me.
If you are trying to actually "hear" that there are speakers in your trunk, cross them over as high as you can.
A big part of higher cross over points "locating" your rear speakers, are harmonics. Harmonic distortion is present in every phase of amplification no mater how good your components are. Harmonics are tones present in reproduced sound at perfect octaves above the source note. For example, and 80hz note will have a 1rst order harmonic of 160hz, and a second order harmonic of 320hz. Each order of harmonic is usually at least 12db down on the source above it. So your 80hz tone at 120 db might have a 108db 160hz harmonic and a 96db 320hz harmonic. The higher the quality of the driver, the further db difference separates the original note from the first harmonic. (this is just a general rule)
Now some people at this point may be wailing " what about my 24db/oct cross over, doesn't that filter out the harmonics?" NO it does not, the harmonics above are sourced at the driver, not before your cross over.
So crossing over your sub at as low a point as possible brings the harmonics produced by the driver into a range less distinctive directionally by the human ear.
Anyone care to correct me?
Adam
People actually have 3 ears.
Say what?
People probably think I'm nuts but I will explain. Your skull acts as your 3rd ear, it sends mono signals to your brain from abient energy in the air. Then your brain takes takes the information from your ears and compares it to the mono signal to derive directional information. This is why wearing something over your skull like a toque decreases spatial awareness. This is also partly why humans become disoriented when high SPL is present. Thus the dizzy feeling with TONS of bass, kind of a natural but damaging high. Higher frequency information naturally has less energy in it, thus it shakes your skull less. This reduces the saturation of energy that overwhelms the directional information from your ears. In short, the higher the frequency, the more sensitive your ears are to location.
My personal experience with moderate level sound in car has led me to believe that frequencies above 50 or 60 hz can easily have their source located. I've further found that chosing as steep a slope as possible for rear mounted subs helps to hide their location. I've tried everything from 12db/oct to 36db/oct. with my subs, and the steeper always seemed to be more musical to me.
If you are trying to actually "hear" that there are speakers in your trunk, cross them over as high as you can.
A big part of higher cross over points "locating" your rear speakers, are harmonics. Harmonic distortion is present in every phase of amplification no mater how good your components are. Harmonics are tones present in reproduced sound at perfect octaves above the source note. For example, and 80hz note will have a 1rst order harmonic of 160hz, and a second order harmonic of 320hz. Each order of harmonic is usually at least 12db down on the source above it. So your 80hz tone at 120 db might have a 108db 160hz harmonic and a 96db 320hz harmonic. The higher the quality of the driver, the further db difference separates the original note from the first harmonic. (this is just a general rule)
Now some people at this point may be wailing " what about my 24db/oct cross over, doesn't that filter out the harmonics?" NO it does not, the harmonics above are sourced at the driver, not before your cross over.
So crossing over your sub at as low a point as possible brings the harmonics produced by the driver into a range less distinctive directionally by the human ear.
Anyone care to correct me?
Adam
06-07-2004, 09:45 AM
#79
1000 Watt CAFz'r
Join Date: Sep 2001
Posts: 1,120
Dat sounds good to me Adam.
In my experience even if you cross over the subs at say 40Hz and below @ 24-36 dB/Oct you will still have directionality issues if anything in the back resonates. As you guys are well aware, everything has it's natural resonance, even your body.
BTW your bowels naturally resonate at 8 Hz at which point you lose your ability to control their output...Great for crowd control, some governments hooked up a MASSIVE sub on a flatdeck to a signal generator and huge amp. Put 8 Hz through it and everyone gets real quiet [img]smile.gif[/img]
In my experience even if you cross over the subs at say 40Hz and below @ 24-36 dB/Oct you will still have directionality issues if anything in the back resonates. As you guys are well aware, everything has it's natural resonance, even your body.
BTW your bowels naturally resonate at 8 Hz at which point you lose your ability to control their output...Great for crowd control, some governments hooked up a MASSIVE sub on a flatdeck to a signal generator and huge amp. Put 8 Hz through it and everyone gets real quiet [img]smile.gif[/img]
06-07-2004, 10:09 AM
#80
1000 Watt CAFz'r
Join Date: Sep 2001
Posts: 1,120
Here's a fascinating link on resonance and infrasound:
http://www.lowertheboom.org/trice/infrasound.htm
Couple of quotes from the link:
"Infrasonic vibrations, though harmful, can be pleasantly stimulating in mild levels. The effects of brief, mild exposure can give a feeling of invigoration for hours. While a person may FEEL invigorated and euphoric, his body is being subjected to an elevated heart rate, elevated blood pressure, a release of endorphins, and the "fight or flight" adrenaline response. Feeling the effects of high-intensity/low-frequency sound can actually become an addiction, partially due to the release of endorphins in the body."
" 43 - 73 Cycles Per Second (Hz) - lack of visual acuity, IQ scores fall to 77% of normal, distortion of spatial orientation, poor muscular coordination, loss of equilibrium, slurred speech, and blackout."
I've always wondered why bass feels good and is addictive, but makes me feel dumber at the same time
.
http://www.lowertheboom.org/trice/infrasound.htm
Couple of quotes from the link:
"Infrasonic vibrations, though harmful, can be pleasantly stimulating in mild levels. The effects of brief, mild exposure can give a feeling of invigoration for hours. While a person may FEEL invigorated and euphoric, his body is being subjected to an elevated heart rate, elevated blood pressure, a release of endorphins, and the "fight or flight" adrenaline response. Feeling the effects of high-intensity/low-frequency sound can actually become an addiction, partially due to the release of endorphins in the body."
" 43 - 73 Cycles Per Second (Hz) - lack of visual acuity, IQ scores fall to 77% of normal, distortion of spatial orientation, poor muscular coordination, loss of equilibrium, slurred speech, and blackout."
I've always wondered why bass feels good and is addictive, but makes me feel dumber at the same time
.
