Which you would hear louder would completely depend on the distance and direction to the concert subs and their content and frequency response compared to your car sub.
If the concert system were to achieve 127dB at 100 meters, it would have to be doing ~161dB at 2 meters, and that ain't happening for most.
The simple answer is the PA array is much further away.
Also simple- in a quiet environment, an average hearing young adult person can hear midrange vocals and electric guitars at <10dB SPL, as can be seen in an equal loudness contour chart:
In an environment with ~40dB SPL background noise, a single PA speaker playing 1kHz at 110dB at 2 meter could be heard at 3km if there are no intervening obstructions, buildings, trees, etc.
That level could be achieved with a single 12"/1" PA speaker with 100watts.
To hear bass below 60Hz at equal loudness, it would need to be ~40dB louder.
From a power perspective, 40dB is the difference between 100 watts and 1 million watts.
A 40dB SPL difference between mids and <60Hz does not happen other than at some EDM festivals.
A 40dB (or more) difference in level between mid frequency and LF outside the car is typical with most subwoofer installations.
I for one am neither young nor adult 😛
The PA sub that went one to one with the JL was an 18" EV ETX. I wonder which one moves more air
The ETX actually reads quite impressive for a PA sub in low extension output. I hope to be able to plug into that too. The specs read more like a something with a pro mobile driver in it instead of PA. Also doesn't look like it would be lacking in fidelity. I could really use the driver they are running. Sounds like it could make the basis of a formidable lil DJ system
According to the sims, my drivers are way quieter than this with the JL barely exeeding 110dB and the DS18 just not clearing 115db, but maybe 4 units in 4x 35L can get close. Can 4x cabs be simulated?
According to the sims, my drivers are way quieter than this with the JL barely exeeding 110dB and the DS18 just not clearing 115db, but maybe 4 units in 4x 35L can get close. Can 4x cabs be simulated?
That’s the ‘Le’ update from awhile back? Thanks for reminding me, I’ve never updated mine
Elaborating on my THD claims...
Let's say that the measured levels are the same. Then obviously the car sub is going to have to work a lot harder, and if it produces a 30Hz tone, the 60, 90, 120Hz etc harmonics will bring up the subjective level.
The dozens of bass bins all stacked side by side and/or vertically probably would be more directional, just based on overall dimensions. Cheers
Let's say that the measured levels are the same. Then obviously the car sub is going to have to work a lot harder, and if it produces a 30Hz tone, the 60, 90, 120Hz etc harmonics will bring up the subjective level.
The dozens of bass bins all stacked side by side and/or vertically probably would be more directional, just based on overall dimensions. Cheers
I saw that the EV sub claims true cardioid over the subs bandwidth. Cant get my head around how this can be done from a single radiating surface but sounds like they mean that the sound just stops on an invisible wall?
Lossy box with resistive damping, probably. Cheaper than using a 2nd driver with opposite phase and dialing down the gain.
Look at Gethain's loudspeakers ( as already pointed some message back) and try to find interview from it's founder ( Joachim Kiesler), they exist and he explain:
https://www.me-geithain.de/en/assets/media/presse_pdf/Studiomagazin-50-Jahre-MEG-06_2010-eng.pdf
Search for D.Gunness patents about it too ( Fulcrum acoustics).
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Bandpass rules!
It's called Transfer Function or Cabin Gain. Even HR can't predict it since vehicles come in all shapes and sizes.
https://www.caraudiohelp.com/newsletter/cabin_gain.html
That's why I remove the rear deck speakers when putting a sub in the trunk.
Very often PA subs have undamped and highly tuned reflex systems.
Maybe additionally audio technicians who do not know how to mix the sound properly.
In 80% of the live events I experience bad mediocre sound. Due to too loud boomy bass overriding the mids.
What I refer to is that PA systems sound loud and undefined.
Car subs often have very stiff cones. PA drivers usually simple unstable paper cones giving bad impulse response.
So no wonder you can follow a bass line better on a well made car sub.
Maybe additionally audio technicians who do not know how to mix the sound properly.
In 80% of the live events I experience bad mediocre sound. Due to too loud boomy bass overriding the mids.
What I refer to is that PA systems sound loud and undefined.
Car subs often have very stiff cones. PA drivers usually simple unstable paper cones giving bad impulse response.
So no wonder you can follow a bass line better on a well made car sub.
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Yes. And with theory you can approximate:
2 cabs wired in series then paralleled with other pair= +6db. Then add +3db ( from doubling of membrane area-sd).
Depending how they are physically located too ( if all on ground you can expect +3db from 4pi to 2pi conditions).
Overall +12db are possible.
This could explain too why you felt there was a difference with your omni box: cardio PA subs are often described as lacking some 'punch' vs omni.
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PA = efficient and play low.
CA = small enclosure and play low.
Hofmann's Law, pick 2!
PA = needs to feed thousands of people.
CA = needs to feed basically the driver.
PA = can be all indoors in controlled temperatures.
CA = is all outdoors with various noncontrolled temperatures when parked.
PA drivers are usually paper cones with cloth or foam surrounds.
CA drivers are usually polypropylene or treated paper with foam or rubber surrounds. Most factory drivers are paper for that PA efficiency and cheapness. That's why the CA industry exists in the 1st place. CA was an afterthought to car manufactures.
2000 Toyota Solara SEV6 factory 6.5" component speakers vs 2019 aftermarket 6.5" component speakers.
It's done with multiple cabinets, and the cardioid pattern is set to be greatest at 60Hz, where it reduces rear level between -6 to -35dB. The rejection is less at other frequencies, but that doesn't make it into the specs.
The ETX-18SP peak output of 135dB would be at around 80Hz.
Peak output is usually somewhere around -10dB below what you would read with a dB meter set to "fast".
Judging by the magnet structure, the DVX3180A driver may have ~12-15mm Xmax.
With the ETX-18SP DSP processing (forget "sensitivity"..) it's response is ~-10dB at 30Hz.
As processed, it's 30Hz output would sound about 1/4 as loud as it's 80Hz level (see the equal loudness chart in post #61).
Probably considerably less loud when the "advanced limiter algorithms for independent peak and thermal transducer protection" kick in 😉 .
The DSP response of the ETX-18SP sub is similar to the raw response of the subs I replaced after finding a car sub had considerbly more low frequency output driving around the plaza than my 4 subs combined response..
Art
Remember when I was taking SPL with the JL at the boat ramp car park a couple of weeks ago. I think you advised to use C weighting. Is my measured 127dB peak not valid then? Is it really only 117dB?
That would be good news as then the ZXI with 115dB average in HR might actually not be as quiet as I imagined
Each of the 4 subs has two voice coils so eight coils total. Each coil will get dedicated 600wrms/1400w dynamic
I don't recall advising you regarding taking SPL readings, don't know what meter you used, it's distance to the source, whether the mic capsule was hand held or ground plane, source material, and what you mean by "peak".
Unweighted or Z-weighting would be preferable to C.
If your meter is accurate, 127dB peak is valid, but...
Depending on the program material's transients, "Slow", "Fast", "Impulse" or "Peak" settings will all give different SPL readings which could vary by well over 12dB.
Using a continuous sine wave, there would only be a 3dB difference.
At any rate, a single SPL reading does not tell you what the level is at different frequencies, 115dB at 30Hz won't seem near as loud as at 100Hz or 1kHz.
As has already been pointed out, putting your cabinet in another cabinet (a car) can have a huge affect on it's output level.
What you consider "quiet" or "loud" is subjective, and may change quite markedly with even short exposure periods.
What is measured is objective, but dependent on the measurement conditions, device settings and placement.