Manual from my first car sub back in the 90s. The highlighted excerpt is something I have now wondering about close to 30yrs. Anyone know why they would say that? If efficiency in not an indicator, then how is upping the voltage in HR any indicator of max potential?
https://jlaudio.widen.net/view/pdf/kord7ddbwr/15_18_W3_MAN.pdf?t.download=true&u=rfhkrg
https://jlaudio.widen.net/view/pdf/kord7ddbwr/15_18_W3_MAN.pdf?t.download=true&u=rfhkrg
They probably say that because the type of cabinet, the amplifier used, and so on play a role in the outcome of "which one is louder". And comparing different builds and installations looking at driver efficiency ignoring everything else would leave people confused as why driver A (86dB/W/m) is louder than driver B (82dB/W/m).
X Damage is more significant parameter in this case imho. + what schiirm stated.
Yes i do.
Lows are not directional for a single direct radiating loudspeaker loaded by a box, but what happen once you take the box out of the equation?
There is now interaction between positive ( front of membrane ) and negative ( rear of driver): driver behave as dipole, hence radiation pattern change to figure of 8.
Directivity management in low end is possible by using this principle: interaction of positive/negative signal + filtering and phase (delay).
It might seems unintuitive but it works.
Use of simulation program to explore this kind of thing is encouraged.
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@Randy Bassinga
Here is the answer to the question that has been bugging you for 30 years.
And no, no "thank you" is necessary. 😉
Here is the answer to the question that has been bugging you for 30 years.
And no, no "thank you" is necessary. 😉
Your car is so loud because the energy from the bass driver is transfered to the sheet metal around it. In sunlight, look at the roof of your car, when your system is putting out loud bass. You will see the roof moving. It is not only the roof but doors and even windows, too. You can feel it with your hand that these parts expand and contract with the beat.
So what we have got is a transfer of energy from a small cone to a very large cone or membrane in the shape of your car.
Some pressure chamber thinks too, but I keep it simple.
This is the same what a horn speaker does: Simplyfied, the cone movement is coupled to the air in the horn and the cone is virtually appearing much larger at the horn exit. You can even put a flexible sheet over the horn exit, basically nothing will change.
You want proof? Take your car audio sub out of the car and place it on the floor. The loud "boom, boom" you like so much, is instandly gone.
You will notice the same if you open all doors and the hatch in a passenger car. The loud anoying bass is gone. My wife experienced it just last saturday, when she cleaned the car...
If still not convinced, think about a 12" woofer. Cut the cone down to a 4 inches and replace the missing part with something solid. Fit some new surround to make it air tight again. Then play the same music. You still got the same power, magnet, coil, spider and excursion, but the bass is gone. Why? Because the small cone can not move the air like the large cone did. It does not couple that good to the atmosphere around it. Air is compressible.
Want more? Even if you are 5 times as strong as your son, if he has a shovel and you only a tea spoon, who is going to move more sand on the beach?
So what we have got is a transfer of energy from a small cone to a very large cone or membrane in the shape of your car.
Some pressure chamber thinks too, but I keep it simple.
This is the same what a horn speaker does: Simplyfied, the cone movement is coupled to the air in the horn and the cone is virtually appearing much larger at the horn exit. You can even put a flexible sheet over the horn exit, basically nothing will change.
You want proof? Take your car audio sub out of the car and place it on the floor. The loud "boom, boom" you like so much, is instandly gone.
You will notice the same if you open all doors and the hatch in a passenger car. The loud anoying bass is gone. My wife experienced it just last saturday, when she cleaned the car...
If still not convinced, think about a 12" woofer. Cut the cone down to a 4 inches and replace the missing part with something solid. Fit some new surround to make it air tight again. Then play the same music. You still got the same power, magnet, coil, spider and excursion, but the bass is gone. Why? Because the small cone can not move the air like the large cone did. It does not couple that good to the atmosphere around it. Air is compressible.
Want more? Even if you are 5 times as strong as your son, if he has a shovel and you only a tea spoon, who is going to move more sand on the beach?
Those car audio kids who don't believe that bass damages hearing are going to look so cool with bilateral hearing aids in their thirties and forties... 😎
At 63 I can hear 15kHz because I've used ear protection when required all my life, despite the jibes about wearing earplugs at AC/DC gigs...
At 63 I can hear 15kHz because I've used ear protection when required all my life, despite the jibes about wearing earplugs at AC/DC gigs...
I single PA 15 sims louder at 1w then a pro mobile sub at 2kw. The standing question is what could possibly allow the car sub to be turned up louder. The way I see it, the PA array is much larger than these cars
The example concert venue has already been mentioned, that it carries the vocals and electric guitars easily to 3km away, why not the bass? We are speaking in the range of band instruments like the electric bass guitar and acoustic kick as well as EDM synth bass and TR kicks
Let's assume that one such car carries an installation designed more for use with the boot open and front doors open, including the ability to use the sub outside the car and routing for a mixer as well as aux main speakers. Using all SQ pro mobile drivers and amps from the premium range by JL Audio and a professional installation by a prominent workshop who took multiple SQ comp wins. Just to prevent further dissing of the industry and its users
Because line arrays are meant to carry everything further. A car sound system doesn't need to carry frequencies above 100Hz any further than a few feet. Concert line arrays are flown and must throw those frequencies much further so there is a completely different reverberant field. But low frequencies escape the car so you hear them. Pro Audio Concert subs could easily send low frequencies that far if they want to. They just don't need to in order to cover a venue. Plus, car sound systems tend to be massively weighted in the 30-50Hz range which would more easily escape the car and be heard while pro audio stuff is heavy above 50Hz. But again, it's all about how hard you're pushing the amplification and what is needed. I just don't think it's that complicated.
Another one is that those concert systems are well tuned. Grands worth of gear.
Not everyone who has a sound system in their car is a boy racer. But it does look that way sometimes. Jamaicans never had that label and a fair few I’ve seen have great sound in their cars. A lot of those guys don’t seem to have the boom sound though. It’s more weight that shakes the floorboards when they’re nearby. Actual floorboard vibration.!
Cheers
Not everyone who has a sound system in their car is a boy racer. But it does look that way sometimes. Jamaicans never had that label and a fair few I’ve seen have great sound in their cars. A lot of those guys don’t seem to have the boom sound though. It’s more weight that shakes the floorboards when they’re nearby. Actual floorboard vibration.!
Cheers
Hatchback cars amplify bass, I got RTA output of 126 dB at 30 hz with a 8 inch Pyle tube and 135 watt amp.
Sound reflection between the buildings? Streets are acting like funnels to guide the sound and therefore it sounds more focused. The car resonating is also a factor.
That has also been raised, but still doesn't answer the output in the range of a 4-string electric bass common to both the stage and car playlist
Let's also bring into consideration the commercial use of pro mobile subs in home hi-fi and studio, with the JL Audio Gotham too
Is it some sort of bandpass effect that allows note perfect delivery of a live bass guitar plugged into the open boot of a Subaru XV at over 120dB, while WinISD predicted barely exceeding 110dB when the box was designed and built 25yrs or so ago?
But then I see discussion which appears to imply things like very large arrays of tapped horns, which must surely drown out a single 12 in the venue car park or is a small hatchback a clearer and more efficient cab than an array of horns?. The car is in line of sight of the stage and can be heard at the sound desk
A couple of years ago we tried to examine this. The music shop that does stage hire has played the little sub inside the store to see what is going on with the seemingly ridiculous amount of clean output while examining the another lil 7" upsetter PC speakers disguised as an instrument amp
I also find people dancing for sheer joy around the car pretty normal, especially on the night street taxi ranks of Sydney City
THD is probably much, much higher with car subs. Pure sine waves played on bass can seem surprisingly quiet if distortion is low, until you get other indicators like a sensation of pressure in the ears, or your clothes start to rustle.
A pure sine wave can be possible on via the synth but a bass guitar string?
An un Eq'ed bass guitar is very loud through a THX certified desktop 2.1 system
If you follow Fourrier theory any signal can be decomposed into an infinity of sinusoidal so... the fundamental of your bass is a sine.
DATSv3 documentation says it's been updated to include new parameters for HF, could there be more to be found for the low end? Also, could a very high lowest end headroom also translate to much higher headroom a bit higher up which may not be getting predicted in the sims?