One thing I can't get my head around;
Why can a single driver based car sub can be heard clearly approaching from the next block and outdoor concert bass cant be heard in the car park? What makes a single low efficiency car 12" inna 35L ported box render basslines clearly inside a mall from the car park?
Why can a single driver based car sub can be heard clearly approaching from the next block and outdoor concert bass cant be heard in the car park? What makes a single low efficiency car 12" inna 35L ported box render basslines clearly inside a mall from the car park?
Stan Curtis addressed this in Linear Audio a few years ago. He built a pair of exponential horns on each side of his basement fireplace in the 1960s, and couldn't hear any difference, but his landlady asked why the noise from the London Underground nearby had got so much worse recently.
I have subwoofers in my own house, and they balance perfectly in the room they're in, but downstairs they are all I can hear.
Wavelength.
EJP
I have subwoofers in my own house, and they balance perfectly in the room they're in, but downstairs they are all I can hear.
Wavelength.
EJP
The concert speakers are likely arranged in a directional cardioid array specifically to minimise side and back spill. It's common practice these days to reduce noise complaints and to keep the bass off the stage.
As William pointed outdoor it's all into the radiation pattern.
In a room it can be different as modes come into play ( but directivity management still have an effect though).
In a room it can be different as modes come into play ( but directivity management still have an effect though).
If you attach a license plate to the concert you'd hear it better. I get my coat.
Because effectively the car is the cabinet. Consider the vehicle a complicated band-pass system; the cabinet being one chamber, the trunk another chamber, and the vehicle interior another.
This sounds reasonable, but $ rules. If this was a real situation, then a single 12" ina car boot parked next to the stage would be ample to bring up the sub 50Hz instead of the speaker array
To all, is this sub 50Hz band that directional that a dispersion pattern makes so much difference?
But how does that explain our situation where they put the stage up facing our way and the sports oval car park?
Also, bass guitar note clarity, this can be very hard to tell apart from what bass that can be heard coming from the concert, Why does the single car 12 render a bassline at that distance better than the PA facing the same way? The guy who runs the music shop here who also does stage hire seemed very impressed when we parked my JLAudio right at the front door of the shop and plugged it in next to the demo PA subs and plug in the bass guitars into the shop mixer. There is a clear difference in definition and authority
We are talking the same wavelengths as the bass guitar and kick drum is common to both the stage and the 70s playlist in the car
Before I bought this car, the JL was fitted to my taxi for three years straight, I drove Sydney to many EDM festivals and noticed the same from the taxi rank. The car sub goes much louder again with EDM kick than the bass guitar and drum
Randy,
Sub 50hz with a bass? You have a 5 string with low B? Cause a typical 4 string doesn't really goes lower than 40/50hz and you usually ear the higher harmonics more than the fundemental. Especially when you talk about 'bass clarity/definition': why most bass players now prefer 10" rather than 15" or 18" on instrument's cab.
There is other things that could be at play too: to have enough low end pressure outdoor you usually need way more sub box than used indoor and it's not often implemented by PA rentals shops if you don't ask for it. With our sound system we ended with +12db (sub 150hz) over what was required for low mid/mid/high to sound 'convincing' outdoor with sub loaded genres.
I'll try to find the recommended overall curve from D&B and JBL systems for you to compare, you'll see it's enlightning...
Sub 50hz with a bass? You have a 5 string with low B? Cause a typical 4 string doesn't really goes lower than 40/50hz and you usually ear the higher harmonics more than the fundemental. Especially when you talk about 'bass clarity/definition': why most bass players now prefer 10" rather than 15" or 18" on instrument's cab.
There is other things that could be at play too: to have enough low end pressure outdoor you usually need way more sub box than used indoor and it's not often implemented by PA rentals shops if you don't ask for it. With our sound system we ended with +12db (sub 150hz) over what was required for low mid/mid/high to sound 'convincing' outdoor with sub loaded genres.
I'll try to find the recommended overall curve from D&B and JBL systems for you to compare, you'll see it's enlightning...
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In sims with HR and WinISD, the car subs are predicted as up to around 20dB quieter than the PA subs at the same bass guitar wavelengths but in actual playback, they appear louder
Trying to understand why
Trying to understand why
I know that, but why does the basslines render with more clarity and authority in the first place, both systems are playing the same material which is the electric bass guitar and acoustic drum kick
I guess the question is, why is the bassline from a Fender Jazz more clear and authoritative coming from a low efficiency car sub when the bassline doesn't contain the wavelengths below 40ish? Why does the PA not drown out the single 12"
This makes sense, my car and home run much more power on the subs than the tops. Only then it sounds convincing with dubby stuff
In my experience this is because you are comparing apples to orange.
First is the PA eqed and dimensioned for outdoor condition? Did you level compensated both source ( they play at same spl)? Have you checked bandwidth of both system? Which one goes louder and at which level of distortion ( high passed with a bit of distortion will sound 'clearer and with more definition)?
😉
First is the PA eqed and dimensioned for outdoor condition? Did you level compensated both source ( they play at same spl)? Have you checked bandwidth of both system? Which one goes louder and at which level of distortion ( high passed with a bit of distortion will sound 'clearer and with more definition)?
😉
How do you then explain HR modelling the car subs up to over 15dB quieter than PA drivers
In the 4 string region, the PA by default with its much larger combined Sd, power and huge box must drown out a single 12"
Let's stick to the 4 string bandwidth for this purpose, so it is more like an apple to a larger apple. Trying to understand why the car sub gets so loud that you can hear it a block away
In the 4 string region, the PA by default with its much larger combined Sd, power and huge box must drown out a single 12"
Let's stick to the 4 string bandwidth for this purpose, so it is more like an apple to a larger apple. Trying to understand why the car sub gets so loud that you can hear it a block away
One reason might be that the car sub is isolated (you don't hear anything above about 100 Hz). At the concert car park you still hear lots of upper frequency contents that masks the bass.
What you said seems to me it might be interesting, but then I remembered that AFAIK the low end of the audible and reproducible range is non-directional.
So I sincerely don't realize how one can force the reproduction of bass frequencies in a cardioid shape... 🤔
I think that maybe your example already contains the answer to your question.
You ask why you don't hear a lot of bass at a concert from the parking.
I guess because it's all outdoors and without reflective and therefore reverberating surfaces that repeatedly and intricately reflect amplifying certain low frequencies.
Then you ask why you can hear the bass frequencies from a car from the next buildings away.
I guess because those bass frequencies bounce off all those high walls of the buildings and surface of the streets and therefore reverberating surfaces that repeatedly and intricately reflect amplifying certain low frequencies.
Can those higher frequencies be that selective as to mask the emanations from a much larger concert array of bass and not mask the emanations from the car?
It's not as if the car sub seems apparently louder only at the very low frequencies, it seems this way over much of the bassline and kick. Why does it
carry so far? In the heyday of car audio in Sydney, I could pretty much tell that a car carrying the now defunct Doran Pro Audio stickers will be going past soon, just about every hour of day and night. Canterbury Bankstown was rife with such little hatchbacks, with a single 12 or 15" and the installer there also favoured cleaner sealed systems in these cars
If there is some sort of bandpass effect happening, then aren't the PA subs an array of some sort of bandpass system much larger than a Suzuki Swift GTI?
It's getting more confusing to understand the distance they carry when sims show these things barely approaching 115dB with kilowatts
https://fohonline.com/articles/tech-feature/cardioid-subwoofer-setups/
Can be implemented passively too but it's tricky. Take a look at Gethain's loudspeakers.
Directionality exist with microphone too and if it happen with mic it can happen with loudspeakers too ( both are transducers and can be seen as mirror image of each others).
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it depends a bit how professional they are, but many outdoor venues actually have stacks/arrays to create cardioids etc to prevent to much noise pollution.
This has all to do with local regulations and legalities.
This has all to do with local regulations and legalities.
Yes, I know that: do you remember? 😉
My point is: no doubt about directionality at all of microphones and louspeakers/drivers, generally speaking.
AFAIK Low frequencies are not directional.
https://www.clearlyautomated.co.uk/blog/a-bit-about-subwoofers
https://www.theaudioblog.org/post/why-high-frequencies-are-directional-and-low-aren-t
So what is your own answer to OP question? 🤔