LOL, make up your mind....... if its an spl box why bother with the 32hz tuning frequency, and if its for sq than having a peek at 51hz isnt ideal. Lemme guess, your one of those guys that believe in the term "SQL", lmao. My original estimate was for the box being played at 32hz or slightly above, not 51hz.
LOL.... Dude your killing me!
BTW- Post some pictures and scores of some of your stuff one of these days....
It's one thing to talk about it, it's another to stick your neck out on the line with the support (and rep) of repected names in audio and do what you say you will....... and not let people down......
Good luck!
I thought it was common knowledge that a car system more closely resembles a bandpass box, rather than a ported box in an anechoic environment?theAnonymous1 said:
In the case of the Durango, they have a 25 cubic foot ported section and a ~40 cubic foot sealed section. The passenger cabin is a significant loading volume, providing considerable acoustic resistance to the drivers, raising the overall peak tuning of the system.
And of course, the higher the SPL, the higher the effective tuning as well, since flexure of panels on the vehicle start to become an issue. The Ql of the system drops, once again affecting the frequency response peak.
And we haven't even talked about sympathetic modes of vehicle panels, which can have a large impact on the system as well...
Surely someone with your extensive experience would understand these points? I shouldn't have to cover the basics with you...
As far as SQL, as a matter of fact I find it a very good descriptive term. Sound Quality and Loudness. A system designed for all-out SPL (such as Scottie Johnson's Bull Pen) just doesn't sound good playing any kind of music. And a system typically designed for extreme sound quality (such as Bob Beatty's BMW) typically doesn't reach extreme SPL levels.
Typically SPL systems are characterized by a higher tuning frequency, and a large midbass (50-90 Hz) peak, with little deep-bass capability. Since most Rap and R&B has the majority of its acoustic output in this range, it's often the goal of the SPL/loud system to accentuate this range.
SQ systems are typically designed to play flat and clean, with no extraneous emphasis on any frequency range. The system should handle organ and R&B equally well, without an abundance of either deep OR upper bass.
An SQL system can be thought of as a cross between the two. Rather than all-out optimization for maximum SPL, the SQL system looks to gain more SPL over a traditional "SQ" setup, while still maintaining good listenability. A street boomer that can play fairly loud but still sounds great at lower and mid-level volumes. Take an SQ system, add a few dB bump in the 40-60 Hz range, and you have your typical SQL system. SPL high enough that most boomers will like it (and enjoy the slightly elevated upper bass range), but still flat enough in response that pure SQ guys won't turn their nose up at it.
Note that I also believe drivers can be designed for car or home use, or for use in both. Many claim a "driver is a driver", but careful selection of the physical parameters of the driver will create a driver that lends itself to better application in a mobile or home environment.
Again, this is because of the radically different nature OF the environments - a small sealed (or not too leaky) chamber, or a much larger (by orders of magnitude) leaky chamber. The response you get from the chamber gain alone is quite different, meaning that you can design a driver to maximize its flat frequency response in a given application.
This is nothing revolutionary, just understanding the application of the driver, and designing the driver with that in mind. Just like Harman engineers do for JBL drivers - design the PA driver with its application in mind...
Dan Wiggins
Adire Audio
Sorry guys, I'm not trying to be an arshole, but your "SQL" box just doesn't impress me. I don't believe in the term "SQL", its the cons of both designs with no pros.
What would have impressed me is a box twice the size tuned at that 51hz. With your estimated cabin gain of 17-18db @ 51hz you could do 157db easy.
I'm not at all blamming the situation on adires product, I'm a firm backer of their speakers(whether they like it or not 😉 ). As a matter of fact my personal SQ setup in my car consists of 4 Shiva's and 2 PR15's. The Shiva's are in a 4cu.ft isobaric PR design. The 2 isobaric pairs allows the box to be half the size needed by 2 Shiva's and lets it handle twice the power.
I drilled a hole in the center of each PR so I could add a bolt going from the inside out so I can take the weight off for spl events.
With all the weight added for SQ the box is tuned to 22hz and sounds amazing. When I'm at a sound off I take all the weight off and burp 2kW @ 43hz and do just over 145db on termlab. The subs could prolly handle a little more power as they still have about 5mm of excursion to work with but I'm not gonna push em that far.
theAnonymous1 <----------------- ANTI-SQL Member since 97'.............ROFL
What would have impressed me is a box twice the size tuned at that 51hz. With your estimated cabin gain of 17-18db @ 51hz you could do 157db easy.
I'm not at all blamming the situation on adires product, I'm a firm backer of their speakers(whether they like it or not 😉 ). As a matter of fact my personal SQ setup in my car consists of 4 Shiva's and 2 PR15's. The Shiva's are in a 4cu.ft isobaric PR design. The 2 isobaric pairs allows the box to be half the size needed by 2 Shiva's and lets it handle twice the power.
I drilled a hole in the center of each PR so I could add a bolt going from the inside out so I can take the weight off for spl events.
With all the weight added for SQ the box is tuned to 22hz and sounds amazing. When I'm at a sound off I take all the weight off and burp 2kW @ 43hz and do just over 145db on termlab. The subs could prolly handle a little more power as they still have about 5mm of excursion to work with but I'm not gonna push em that far.
theAnonymous1 <----------------- ANTI-SQL Member since 97'.............ROFL
😀 aight....theAnonymous1 said:
Why is that impressive again? Why is easy impressive? And what program told you double the box tuned to 51 would make you a magic 157 with what port area?theAnonymous1 said:
Wow.... yea please...don't blame the product... LOL...theAnonymous1 said:
How many grams is it when its loadedtheAnonymous1 said:
How many grams is it when its unloaded
Thats alot of power for such a low score.... what are you doing wrong?theAnonymous1 said:
What "Sound Off" do you attend...it should be posted on their site...whats the link and your name so we can see?
Got a pic of this iso passive setup ?
Problem is, as you increase SPL, you don't gain those "linear" additions that the programs show. Air starts to act nonlinear as you push 150 dB, and the vehicle walls definitely start to act nonlinear at above 140... So you can't assume that just because you get 17 dB of boost at 145-150 dB, you'll have that at 157 dB. In fact, it's often the case that changes that should result in 2-3 dB (like doubling power) rarely gains you more than half a dB, when you're at these levels of pressure...
Dan Wiggins
Adire Audio
Dan Wiggins
Adire Audio
Good, I'm glad you guys find me so entertaining 🙂 .
I used 51hz as a reference to the frequency its loudest at now. Port area has nothing to do with how loud a box will be as long as A: its not so large as to affect how the box "sees" it as a port and B: not so small that the mach speed is high.
1000 grams each
300 grams each
LOL, I don't know how the competition where you live holds up, but there isn't anyone locally that can hit 145db with 2 12's and any amount of power. Especially with a box thats only 4cu.ft.
My employer, a local car audio and paint shop holds an unaffiliated DB drag event every Wednesday at the local mall. I will not give their name do to the negative response I'm getting from you fellas(expected as it is).
I would love to upload some picks of my setup, but that would require a digital camera that I do not posses. I'll see if I can borrow one and get the picks up as soon as possible.
One last note, I am more than willing to admit that Dan Wiggins is MUCH more knowledgeable than me in this field.
Dan = age 40+? and wise
Me= age 24 and......well.....whatever most 24 year olds are
My original estimate assuming you were gonna burp at or close to the tuning frequency like 99% of the people who come to our local event do.
I only guestimated an extra .5db at 32hz over 51 because I know cabin gain is extremely non-linear and the fact that its only a little more than half an octive lower.
I only guestimated an extra .5db at 32hz over 51 because I know cabin gain is extremely non-linear and the fact that its only a little more than half an octive lower.
Attachments
theAnonymous1 said:
😀
Port area has nothing to do with how loud a box will be....theAnonymous1 said:
Wow.......
😀 I've wasted a lot of time...
theAnonymous1 said:
You'd get killed 151+db at 2200w with 2 12's.
http://incriminatoraudio.com/mm/DSC02298.JPG
Didn't ask for his name...asked for yours...buttheAnonymous1 said:
since its a weekly "unaffiliated" event...its not a sanctioned body event which means.....no proof, your name and score won't be posted on any sanctioned body event results , and you probably have no real head to head competition with true core competitors....
Interesting...sq guys always have pics of their stuff....theAnonymous1 said:
Ok...you can stop now then...theAnonymous1 said:
I listen to it, I don't stare at it. What, am I supposed to capture the essence of the sound quality in a pic? 🙄
Example, say you have a box with 100sq.in of port and at full power the peek mach speed is 5% or less, than having a larger port will do next to nothing. If you go too large the box doesn't "see" it as a port anymore, it sees it as more box volume or worse, an infinite baffle.
Ok...I will... 😉
theAnonymous1 said:
😀 almost ...ALL sq competitors have a portfolio of their installs...and in MOST sq competition...its required to have such a portfolio. Any real competitor would know such a thing...
yea...but you said....the size doesn't matter in spl unless its too big or too small...and see.... 😀 it does matter..... if it can't be too big or too small...what size does it have to be??????? that comes from knowing your craft.....theAnonymous1 said:
And playing on bassbox pro isn't gonna tell you that 😉 .... you have to tell it how much port area to use....and YOU have to know how much for what kind of application..... which you don't LOL..
theAnonymous1 said:
😀 good...cause everybody is laughing at you.
Hey theAnonymous1-
I drilled some "reverse aperiodic" dampening holes in my Tempest cones and gained another 10db.
You should try it! It's cutting edge stuff.......
🙂
I drilled some "reverse aperiodic" dampening holes in my Tempest cones and gained another 10db.
You should try it! It's cutting edge stuff.......
🙂
95Honda said:
Hey thats what that is called, "reverse aperiodic" I heard of that too, and I will be doing that to my subs as well. I think it is critical to have alternating large and small holes, and distance apart depends on hole sizes and cone size.
I cant wait, 10db oh boy
To say "Well said" is understatement, but I'll say it anyway. 🙂DanWiggins said:
Aside from the current urinating contest, I've learned never to trust box software. Even excellent software does not properly take into account the specific effects of a vehicle. They make for good guidelines, but if it was that easy, then people would just bring their laptops to an SPL competition, and run simulations, instead of actually MEASURING anything, and taking the chance of blowing an expensive woofer. Maybe pound a little bass out for the crowds...
Personally, I'm not a dB guy. My car puts out a paltry 130 dB, (The highest I've ever recorded was 132 with current equipment.) That's running from a pair of 10" subs powered by 130W or so. I'm running less than 300W total system power.
My first sub box was built using WinISD, and it sucked. Too little low bass, and way too much at about 60Hz or so, then a huge gap at the 100Hz mark where it was supposed to roll off to the mids. I broke that box up for scrap. The next attempt, I put in a temporary simple sealed box, with a simple predictable anechoic response, then put it in the back of the car, and MEASURED it. From this, I got an idea of what the cabin gain curve looked like at the kinds of power levels that I was dealing with. Back to the drawing board, using that curve as a starting point, and I ended up building boxes that everything said was too small. They sound excellent. I also made other changes, but when crossed over at 80Hz, they're quite smooth down to 25 Hz, with a -4dB at 20Hz and a slight (2dB) peak at 31.5Hz. I more typically run them crossed over at 50Hz, with a midbass driver going from 50 to 200Hz, but since I sold off my midbass units this spring, that's currently not the setup.
In any case, I guess that my point is: "In theory, there is no difference between theory and practice, but in practice, there is."
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