Box modeling software is supposed to help you design an enclosure for your speakers, but they can be very wrong, especially in a car. Purchase your car audio from www.emfcaraudio.com and get our expertise too.
been using my bassbox pro for many years and never led me wrong..90 percent of guys who use these programs know its all open field results i hope......at the institute we simulated boxes using WIN ISD tested them with audiocontrol RTA outside. 4 different boxes with 4 different tunings and they were spot on..then we did cabin gain results with different cars to see how much gain you get and the numbers go way up..no program can get those numbers right but if used correctly these programs are life savers but i dont put 50 grand in a build to play a 20 second bass note thats a whole different animal ....all these big time name brand car audio guys have some sweet products but all of these videos are biased in one way or another
Correct, but that isn't what people use it for. It will never be in an open space unless it's outdoor PA. That's the purpose of the video, to show it's not accurate when the environment isn't considered.
I can't believe this idiot thinks he's teaching others? Of course you measure and apply cabin gain when designing a system. Why is he designing the system to be peaky? Why would somebody want that? Truly the pursuit of an idiot!
@@EMFAudio Your video ended up being reposted on a speaker builder forum and had us all LOL. You know what? You're taking the time to reply to everyone's question or comment (even the hostile one's....) Good on you! That say's something! I took the time to look at your site a little bit...… I have to say those Banhammer subwoofers look impressive! Linear spiders on a car audio sub? Usually they have progressive spiders so you can mindlessly drive them with Gigawatts and get subjectively higher output and lower distortion while experiencing fewer failures. Of course linear spiders have lower distortion when used within Xmax and why would a sensibly used subwoofer fail? Peace!
Only way is to build the box, then test it in action and see if you like the sound. Building spec sheet boxes can work, it can produce excellent sound but knowing your subwoofer is the most important part, and doing live testing!!
The software shows the port being inside the box. Does the software assume the port volume is separate from the 1.5 cu.ft. or does it consider it a part of? When I used to work at a car and truck accessory shop, Kove audio always recommended that we add the port to the existing internal like your video shows keeping the internal box volume unchanged by the port. So I was wondering how the software calculates. Hope that makes sense. Lol!
Unfortunately, you don't seem to know how to apply the software correctly. The software is only as good as the data input or lack there of. As you did not account for the cabin gain, power applied, etc your application is what is wrong, not the software. Ive designed and built hundreds of subs for pa, home, fixed application, and car. Made many of the same mistakes you did too. With correct use, I learned from those errors. Hopefully, you will learn that as well.
@@jamesbondcaraudio4247ah got ya. At this point, I don't see the need to introduce yet another driver to the market. I have someone that can build me about any driver I can imagine. Plus I work with many different manufacturers.
I think you should do a build that show cases your budget equipment but maybe something like 6 12inch low ballers and show off the efficiency of the subs by showing term lab results and by using smaller amps rather then everyone else killing it with huge power . Make it a budget build that puts out some solid numbers show the new base heads whats possible on a budget while also showing off your skills amd experience on box builds and so on. Also maybe a build that allowes for a box exchange or swap out to try out all your equipment.. something that keeps ppl interested and involved by taking thier advice like you are today. Great idea!!
So I think the difference in this example is the distance to the loading wall. When you add the port length it shortens the distance to the back of the car changing the tuning drastically. A good test for this is to put the short ports back on it and move the box back then retest. My friend ran in a mod street class and if we moved his box back towards the back of his Blazer, it would change his tuning and his peak without changing port length.
When you change the box position you aren't changing the tuning, you're changing the distance from the sub to the sensor. That's changing the environment. Now, where it could change tuning is if the port opening is equal to or less than the port diameter from a surface. That will change the effective port length. That applies to inside the box as well.
how does changing the port length extending into and (overall length )the enclosure effect tuning and SPL? i.e. say I had an adjustable (big ass ports type), 10" on my twin 18" subs, and I could adjust both the overall port length and the amount of port in the enclosure, would this be beneficial and if so how? thank you!
When you add length inside the enclosure you take up volume, so even with the same port length that will change tuning. As far as the dynamics of the port inside the enclosure goes, there are documented cases where having the flange inside the box was louder (not audible, but measurable). However, that will be a case by case basis based on other enclosure dimensions.
Nice test. One thing i wil say. The program don't Simulate Kompresjon factor inside Cabin and the box. This happened when you test it on to much power, the Software gets incorrect. Try a sinus test from 100 to 10 hz att say 1 to 10 watts then the Kompresjon factor is not that high inside the cabin and the software will be a little better :) but i understand i have tested it my self. I have tested in my car the software says it peak at 29 hz then i tested with 1 to 10 watt and it peked att 28-29 hz correct, but when i turned up the volume to close max it peaked att 40 hz ^^
Great video. I must say this is the 3rd time watching. Just for fun I'm waiting my my buddy with his termlab so I can play around. Happy New Year and nothing but best wishes.
Suggestion for a follow up video to this is finding the vehicles peak and how it affects the actual overall peak based on the known peaks of vehicle and enclosures. With both a box designed/tuned for the vehicle's peak and one designed/tuned at least an octave lower, even lower if possible. Should make for some interesting video tech.
That might end up being a 2 hour video LOL. As the vehicle changes with pressure, peaks change. As you reach port velocity limitations, peaks change. I think it might end up being a fruitless effort, but maybe it would show the conditions it works and doesn't work.
Understood, I know time is valuable. It would have given layman like me a better understanding of overall system tuning after all the hard work. Sometimes the science just needs to be broken down to consumable video(s). Just like you already been creating. A "break down the science" series maybe? Keep up the great vids. Thx for taking time to respond.
2:34 your time circuits are wrong... one display shows 1986 while the other two displays show 1988... you're going to rip a hole in the space time continuum!!!
It be nice if they were in the ballpark, but when they are in another state, or not even playing the same game, as reality.. What good are they?? I have never used this to build a enclosure, but was thinking about it... I usually built by available space, and used a sub that works in the space, in a sealed enclosure, I am thinking about putting together a 4th, for 4x 12" on about 4kw, nice to know this now, maybe I'll just go oldschool, sealed, where tuning is done by volume, and power! Or maybe do the copy cat!!
Hi EMF, really loving the technical approach to your videos. I was wondering if you could do one on the topic of small signal vs. large signal parameters in regards to box modelling (if there is someway to measure is as open space as possible i.e. no cabin loading, or half or quarter-space loading for that matter). I am interested on seeing the correlation of the sub-woofer sensitivity parameters vs. true SPL on sub-bass, say
That is a great idea but it would be very expensive. I'd have to test in an anechoic chamber which I would have to build or rent (no idea where one is near me). I would also have to use a driver that has already been Klippel tested or send one of ours to do that (very expensive). That's all before getting into building materials. Your theory is correct and it would be interesting to see that difference but it may have to wait till these videos are making more than $5.
Hmm, I modeled my sub in WinISD and It's very close if not dead on what my subwoofer does in my room. I'm using a slightly older version, and it has issues with the voicecoils (could also be the way I input it) and it throws off the measurements by a LOT. But when I fix it it's pretty close, much closer than in this video. I'd be curious to see this test done again with a different subwoofer possibly. (make it easier and use a single sub instead of 2) Not because I doubt this video, but the more samples the better right? Maybe make it easier and go sealed and see how the one models in the car and software. Then grab a basic ported box (like off the shelf slot port or something) and throw that into the software and compare it to the real world car test. For science lol.
I have Eminence Designer software which allows you to select and adjust the acoustical environment. Being in car or architectural and also allows for adjustment of air temperature and barometric pressures. Really great software.
@@EMFAudio Never really tried to see if it is but maybe that is a project for this weekend. And eminence releases updates for it on a regular basis too so what your saying means they dump alot of programming money into a program that simply doesnt work. Kind of a huge accounting issue for a big company like Eminence for sure. Do you consider these to be at least more accurate or still just way off?
I've found it quite common that TS params from the manufacturer weren't even close to what I measured from a purchased speaker. Maybe they measure them on the prototype and then ship what they get from manufacturing instead of taking random samples from manufacturing and averaging those values. I often see measurable differences between two sequentially numbered serial number woofers. I would always measure my speakers TS params myself before building a box.
Many manufacturers either push catalog subs that they get figures from the build house and hope it's right, or they get them from freshly built speakers that have zero play time on them. It is common to find a small variance between two "identical" speakers, but in the big picture you won't hear those differences.
When clamping power I'm looking at wattage only, not voltage and current individually. That's the only way to gaurentee it's always the same exact wattage.
@@_N_B_0496 My brain. You can get an idea of what the sub will do with software but the cabin gain will take some general knowledge. Bigger vehicles like a minivan without a wall will peak lower, like in the low 40's or maybe even high 30's. Smaller vehicles like a compact hatchback will peak higher, high 50's and low 60's. How much they'll gain is unknown so you have to build and adjust or use an RTA and EQ to adjust after it's installed.
The same results apply. The issue is it can't predict the environment properly and it doesn't know how the sub acts with more than a millimeter of movement.
Since, I’m an engineer, I would use the kiss principal when build a box and go with a sealed design because they have the highest SQ, and are forgiving.
Cant help but wonder if when adding 6” of port you also moved box forward 6” you know only making one change and making it more controlled. Port being 6” closer to hatch wall def plays a part imo
That can be true, though you'd also be changing the sub location so you're changing 2 things at once. Beyond that, in this car the port end just needs to be in a range from the back. No less than 4" and no more than 12" and the result is no different.
Well it's because those software does the calculations on an ideal open area, right at 1 meter from the sub or the port. What the bad thing about these programs is that except if you can get your car acoustically analyzed you never get the results you want! Example: On BassBox 6 Pro there is a tab dedicated to the acoustic behavior of the car. If you cannot add the data(and most of us can't) the program is off on the calculations *in* *the* *car*. SO all in all it's the fault of the software since they can't even provide us an idealistic in-car environment for a basis on response. Think about it.
I'm not sure it's really possible for the software to calculate how a setup will respond in a vehicle without some input from the person designing the system. Even then, what works for one guy might not work for the next because one might have deadening in their car or the other took out the back seat. You can't generalize and expect accuracy. Hence the reason why these software applications are just an estimation
Hey man I'm gonna go ahead and let you know I appreciate this video. In the past I spent hours modeling different subs deciding which to buy. Settled on one and built the box. It peaked pretty hard, which I was hoping to avoid. That's when I learned about cabin gain. Since then I've seen people on forums and places doing the same thing. Or saying that X sub doesn't model well and whatnot. So these high and mighty critiques on here that know everything, well screw them because those of us that do exactly what you're telling us not to do are grateful for the explanation. So yeah thanks. A modeled response is not equal to real world in car response. Open the window and it changes, open the trunk and everything changes again, though probably closer to the model.
You measure it, you don't calculate it. There isn't a formula to do the math on it and it is dynamic in that it changes with pressure and panel movement.
I'd like to disagree, the modeling software is very correct, actually scary correct usually. You just need to actually understand the software and use it for its intended purpose. Winisd can stimulate driver behavior on a basic level when it comes extension, excursion, port speed and the like. Programs like hornresp can simulate complex, folded horn designs within a couple dBs of accuracy. Belive me I've simulated folded and measured several horns, as well as ported designs. If the results don't match your doing it wrong it's not rocket science or magic. Get some proper measuring equipment and do them in the correct environment. If you're simulating in a 2 or 4 pi environment, and then measure in a totally different environment.. The results will not match. It's like testing a cars 0-60 time in a 45* slope with 10 cement bags loaded and complain that the published numbers from the manufacturer are incorrect. The software does accuracy simulate your box to a scary degree or accuracy. If you or anybody else is unable to comprehend, understand, or apply the data, to a real world scenario it's not the softwares fault. The descrepancy between your simulations and your measurements are not due to the software or your box.. It's the error of measuring it incorrectly. What you are attempting is measuring the effect of the cars acoustic effect on a simulated frequency response.
You've apparently not watched the video. I specifically say why it's not accurate. Also feel free to provide proof of being accurate from modelling to real world.
@@EMFAudio I have watched the video, the point remains. The simulation for its intended purpose is correct. If you put your box in the space the simulation actually was intended for and measure it, you'll most likely find that the programs numbers and response curves match up pretty well. What you are measuring is the response of your cars interior more or less, it's an easily pressurized small confined space... Not a 2 or 4 pi environment. What you are simulating is the product of the box and drivers ONLY. Here's a quick sim of a sealed Dayton RSS390HF in a livingroom, measurements taken with REW using a calibrated umik at listening position, sims were done in hornresp with manufacturer data and was merged with the rooms measured responsecurve. Which by the way is silly closed to the simulated curve anyhow. Just take the roomnodes, gain and measurement position into account. imgur.com/fikKl4d You could measure the response in your car at a specified place, then take that very same sub and put it in an open space without extra boundaries to reinforce or influence the gain. Then simply make a responsecurve that accounts for the differences. Subtract that curve from the measurement in the car and it will very likely line up very close to the sims. If you don't take your car into account when simulating, I can agree that the data is not as useful. But not useful does not mean incorrect or wrong, simply misinterpreted or used for the wrong purpose. Otherwise just head over to avsforum or databass and check out the horns a lot of us are simulating, folding, unfolding and then building.. If you do it right it ends up very close, granted you measure in the space it was simulated. Sims are not wrong just because the data is applied or read incorrectly.
@@TheDaniel85So what you've proven, by your own admission, is they aren't accurate. You said if you take into account room nodes, gain, and measurement position IE inject your own input contributed by the environment. Seems like that's the same thing as in a car. You have to adjust to the environment, you just said that, just like I've been saying all along. It isn't an exact match in your case either. Bottom line, the simulations may be right if you're in an anechoic chamber, but nobody is, which means the result is bogus. At no point in my video did I say in an open area with nothing there it would be wrong, I clearly stated what it doesn't compensate for and why it shouldn't be used for that application. I will reiterate the point that PEOPLE USE IT FOR THIS APPLICATION. I'm showing why you shouldn't, but you're arguing something that doesn't need to be argued because you live and die by graphs and not reality making excuses.
@@EMFAudio They are accurate, as long as you use them correctly. As I stated before, what you are simulating is actually only the box and driver. The box itself performs and behaves more or less the same in a car as on an open field.. it does not care where it is, it's behavior does not change. Just the response due to enviromental factors. The room or in your case, a car is separate matter and another issue entirely even if you can simulate for just about everything with proper work and measurements. When designing subwoofers, boxes, and speakers you NEED to know how your design functions and actually work. So you can accurately determine expected raw output, excursion maximums and minimums, identify problematic areas such as acoustic impedance, possible resonances and general driver behavior. That is sound engineering practice and common knowledge. Doing complex designs and getting predictable results would not be possible without said software or at least a lot of time crunching the math by hand. Then if the room, or car alters the response, then that's a another problem in its own that can be mitigated by treatment, placement or simply integrated into the design decisions. What I object to is the 'clickbaity' statement in the title of the video, and the disregard for good engineering practices when designing a box. It's the same when designing a multi way speaker from the ground up, you design and measure in an open / anechoic environment or use gated measurements blended with nearfield + port. The room is treated as separate entity. I do get your point that people not understanding the software or not using it for its intended purposes might not get what they expect, but the software is not at fault usually. Simulation software should ALWAYS be used in this application, even if the results are not a reflection of the performance in the car, for the simple reason that it gives you a box that is tuned properly and well suited and optimized for the drivers... And the car if you do your home work. Car audio is not an exception from the laws of physics. Best in my opinion would be to tell people on how to actually use the software correctly and why the raw/uncompensated simulated response does not match the actually measured in the car. But then again, perhaps due to my engineering studies and fondness of designing horns and speakers I might approach the issue differently. That's just my 5 cents, I think we will agree to disagree on this.
Ive always preferred the trial and error method, opposed to doing it on a computer. Seems pointless imo, because no matter what, it's gonna be different in the car, most of the time T/S parameters are gonna be way off, because every sub is different, so you'd have to measure all of that to even begin to do it right. Idk lol, building is more appeasing to me lol. I built probably 9 boxes for my hdc315 before i got the right one in my z32! Im glad i didnt stop too lol. This wolfram AU goes harddddd in that box 👌🏻.
Our sub specs are right, and they're all close. We have high quality control and measured the specs in house after break in. We didn't pick a catalog and publish the specs they put out. But, the more experience you have the less error you have. The trial becomes predictable so you only have to build once.
I know yall do your stuff right, i watch all your vids! Lol. And, im getting there. Things are starting to sound the way i want them to, the first try around lol
Very cool video. Love your channel. Bass box pro assumes your port is taking up enclosure air space. That is why the frequency went up when the port length increased (I'm sure you know that). If cabin gain was also included (there is an option for it) it might be closer. In 1/2 space anechoic modeling it is more accurate. Why didnt you keep the port distance from the rear of the car the same so that the exiting port pressure is equal to the hatch? Seems like the resonant frequency of the cabin is 65hz. Again, most modeling software is not accurate for SPL comps. For the layman this would be very misleading. Thank you for sharing! Keep up the good work.
When you tell it the port is external, it doesn't assume taking up volume. It also bases it's numbers off of net, not gross so if it was taking up volume it wouldn't change the calculations unless you force box dimensions instead of setting a static volume. There is an option for cabin gain, but where do you get that info from? It's not dimensions. you'd have to have acoustic measurements. What happens when you increase SPL? Panels move, metal resonates, and all those numbers are wrong unless you measured them at the same SPL. I didn't keep the port distance the same because then the sub position would change. I know the sub position is optimal no matter the port length.
@@EMFAudio forgot about that part of the software that tells you internal or external. Thank you for your reply and information. I still have a lot to learn.
@@EMFAudio ... I truly like how you teach the science behind audio. I've been into audio since the early 90s; never knew I'd pick a "cool" hobby that required so much mathematical & scientific enthusiasm. 👍😎👍
I never used a program to build a box I’m going to put a hole in it.... by the way the manufacturer already tells you the parameters to build... ie optimum sealed/ ported with optimum port size... why waste time playing on the computer when you could already have your box built and banging
@@EMFAudio Correct. The software isn't modeling the speaker behavior in a car but in free air. You have to model how the speaker will behave in the environment that contains it. That isn't what most box modeling software does.
Box modelling software typically uses t/s parameters, which are SMALL SIGNAL parameters. They will not accurately model a system driven to its SPL limits - because their predictions are based on SMALL SIGNAL parameters. And while some of those box modelling programs will allow the user to see what the impact of a car's measured transfer function would be, very few, if any of them can accurately predict other factors like vent compression or impedance changes due to a voice coil heating up that will affect the output at peak SPL levels.
@@EMFAudio If you mis-use a tool like software-modelling using small-signal parameters to try to estimate a speaker's performance at high SPL levels, then you won't get the results you expect. It's not that the software modelling is wrong. It's that it's the wrong tool to use for this specific type of use. It's like trying to use a hammer when a Dremel is required, and complaining that the hammer gave bad results. Well, duh, LOL. There are some techniques that can be used to bring the software modelling predictions closer in alignment with real-world measured results, like measuring the t/s parameters at a higher input voltage and using those for modelling purposes, but you will never get perfect alignment because the software modelling does not know and cannot predict things like how the car's interior will impact the response at high SPL levels, or how much vent compression is going to impact the response of the vent at very high input levels. That's where experience and fine-tuning is needed. Software modelling will get you to the baseball park. Experience and fine-tuning will get you on to first base :-)
I just noticed something else - one of the box modelling software programs that you're using shows a flat or rising response at higher frequencies, and an impedance curve that gets flatter at higher frequencies. This suggests that at the very least it does not take driver inductance into consideration, and certainly does not take into consideration other factors that can impact predicted output like semi-inductance. And the other program does not show the semi-inductance parameters in the input dialog boxes. For high inductance, low impedance drivers like car audio drivers, these factors can significantly impact the accuracy of the model. For more information - www.diysubwoofers.org/misc/semi-inductance.html
@@Grommet2007 It's not misusing a tool when it's using it how they intend. Is every single driver already in their database Kilippel tested? No! That means they supply driver data themselves in small signal and that's how they intend to use it. I am aware on the inductance variations, I did a video on it over a month ago. Go back and watch the whole Tech Stuff Tuesday series. The fact is, the simulations aren't perfect, if they were they both match then you could try to blame the user. They're just not accurate, that was the point of the video.
@@EMFAudio If you're using driver parameters from a database rather than ones you've measured yourself, then you're already losing accuracy. Some manufacturers publish accurate parameters for their drivers. Others, not so much. And if you're using a software tool that is not designed to predict SPL output at very high input levels in a closed environment like a car's cabin, then of course the results will not match what the software tool predicts. It's not that the software tool is "wrong". It's that you are not using it correctly. If I use a hammer to drive a screw, the hammer is not wrong, it's my use of it for that purpose that's wrong. As for the different predictions between the two software tools you used, then that suggests that one is more accurate than the other. I'd place my bet on the one that's modelling the impact of the driver's inductance and the impact of the vent's pipe resonance modes on the overall response as being the more accurate of the two.
my SKAR called for 2.0 cubic foot box 32 hz .. i have a prefab 3/4 box that sounds great, same box worked wonders for my audio pipe that called for the same settings but at 33hz tune, which this box is. after seeing this video i'm glad i went with a pre fab instead of designing my own and thinking it was good. but i do wonder if depth and width according to manf specs actually matter, so long as cubic foot is the same...
so ppl out here getting custom boxes for a bangin' system, but just need to follow manufacturers specs and they are all set. crazy how simple that is. of course i say that statement assuming ppl play at tune
it's simply amazing what those ports let you do. when you said 1.5 cubic feet it made me realize how much space your port had added, i'll assume that's what let's you play below
This is the same as putting your sub box in another bigger box, aka car/room. You will get different results. Dont design a box for an open environment if it is not going to be in an open environment. It would be like designing a freeway system for a Kansas plain and dropping it in downtown SF. It wont flow the same. Design your box for the environment, dont design the environment around your box.
I was under the impression that Sub Manufactures model their subs in software similar to this to determine recommended enclosure to include in their product manuals. Sooo, what your saying is that Sub Manufacturers should not use any software modeling when determining recommended enclosure designs? They should instead place them in every possible vehicle on the market, testing every possible enclosure size and port configuration in each of those vehicles and then what? Just determine an average of which one is best? Because I'm pretty sure if I was designing and building subwoofers as a company it would make sense to be modeling my product in some sort of enclosure design software to come up with a recommended enclosure, perhaps test a few that the program spits out and go from there. But simply throwing out modeling software as totally useless is wrong in my opinion.... PS - The vast majority of your videos are very informative, keep up the good work!
In car testing is more than just a spec too, it's also placement of the sub and port in the box and how those are placed in the car. We actually do in car testing on prototypes before making the final product. When you've been doing it long enough, you just kind of know what's gonna work and not work based off the parameters.
I'd be good if software could account for the environment you're firing into, though I suppose it's more than volume, its also geometry. Possibly advanced 3D modelling could do this, but at that point the software wouldn't be worth more than time invested in trial and error. Built a 6th order for my car, +5dB at 55Hz, +2dB at 30, and its got a whopping peak at 30, way more than 50. Cabin gain is an incredibly major factor in box design. As for why the software was off (as in the 3dB gap between boxes), my guess is the subs are more efficient than the software was treating them. They could be in a node, too, which should load the drivers a tad more, which is maybe why 4.5 went down to 4.2. From my experience, electrical data is reliable in software. Good video though, the title seems to have brought in trolls.
There is more to the environment than volume and geometry as well. It's also the contents, both shape and material. Example, seat positions change SPL, sometimes significantly. Seat materials, door panel materials, headliner materials, all factors as well. You'd have to account for dampening of each of those things too. And, if that wasn't enough, the environment changing at different SPL. The ones you're calling trolls are people that live and die by the graph, in non-automotive applications. One tried to bring in a car and was measuring at 118 dB showing how close it was. When the vehicle starts moving from the pressure, the environment changes. That's also why you can add deadener (changing the resonant frequency of panels) and it will change your response.
@@EMFAudio Yeah, really is a pain in the ass. Probably a good thing if it stays this way though, if modelling software got too good, whats the point going to competitions? You'd only need to submit a design. I remember an exo video, the one with the deaf bonce 15", where he improves his score by tilting and sliding his seats forward. I'd love to fiddle around with a term lab or something, but can't justify spending the money on one at the moment.
All this says is that cabin gain at the tuning frequency is the dominant determining factor in this case. In a small car cabin gain will be as much as 24db by 60 hz. Cabin gain is easily sumarized at 12db/octave below turnover. When considering all 3 dimensions and the modes of resonance the result you measure is almost normal. All you are doing is saying that you need to test. Theres nothing wtong with the software whatsoever.
@@EMFAudio Thank you for the reply. On the basis of what you said, I suppose that the goal was SPL... Anyway, if SPL isn't the goal, the higher the size of the sub, the lower you can go and lower you should go, because you can gain more bandwidth and so deeper bass. The higher the power, the lower the tuning frequency should also be (if it is possible), because high frequencies at high power can damage more easily your ears.
@@skmax521 That's not accurate either. I've tuned 8's to 35 hz quite a bit, that's pretty normal. It's not a relationship to cone size, it's a relationship to the subs suspension and characteristics.
@@EMFAudio I agree with you about charachteristics and suspension, but almost always the size matters. A 12inch sub of the same collection of the 8inch can play better at 35Hz compared to this one...
your first problem is your spl meter is stsrting out at 100. db's is all wro g in a normal room resting db's should be around 65 or so. now get that set right then start your test
Your first problem is starting a comment with "your first problem is". Inside that car isn't a "normal room". Closing a door will read on an SPL meter. Additionally, that meter won't read accurately below 120 dB nor it will ever show below 92 dB or so. The numbers being shown in the video are well above the threshold of accuracy. 140 dB is 140 dB if you started at 100 dB or 65 dB. It's not decibel addition.
First of all, get a good sub in a sealed box and run a sweep and measure how you car handle it. Later that you can have a good start point to choose what is the best frequency to have a great peak number! Dont say the software is wrong if you dont use it in the correct way. Here in Brasil we have a most popular kind of sound system to play in open area instead of inside a car. And i run WinIsd pro and have great results. Inside a car, a software cant simulate how your car will handle the sound. And this dont means the software are wrong! In real world in a open area, it works very close to the reality! Check out my older videos on my channel to take note about what kind of stuff im talking about.
First of all, the sealed box method doesn't work. When you increase pressure in the car everything changes. If you don't have the same exact sub position everything changes. The introduction of ports changes everything. If you don't have a perfect 0.7 alignment on the sealed box, it won't be accurate to begin with. In short, it doesn't work, especially if you aren't in the neighborhood of the same SPL. The software is wrong, I showed it's wrong in multiple ways. For starters, both softwares gave different results, this means one of them is wrong even if one of them is right. The software can not accurately predict the car. There are factors with metal resonance, interior panel materials, etc. There are settings for "in car" so you can't say it's not intended for a car either.
@@EMFAudio in open space it works pretty nicely. In car, thats true, it doesnt have how to simulate exactly the reality of any vehicle, but it works better if you have a calculated sub box vs if you use a wood cube with a hole and a tube. If the software is wrong, what is the correct way to calculate te perfect box for a sub in a car?
@@guilhermeleffler The math for tuning is fine, because that's math with no variables. The plotted response is an estimated simulation, not reality. THAT is the point. People go off of graphs with bad information. I'll remind you that both programs gave different results. That means even in open space, at least one of them is wrong.
@@guilhermeleffler So you designed the box, built the box, installed it, and compared those results to an RTA graph that matched it exactly? Or did you just go "that sounds fine"? I do that without using software making educated guesses.
Not so fast my friend, the simulation software is about simulation right? But the software itself won't do things for you, please share with us the parameters you input, the cabin gain simulation vs free air. I agree with you the SPL inside the car cannot be predictable, you need to measure real world. Regarding the ports, there are many factors like the flare, BBP uses a nominal radius, cannot be customized. You didn't show us how you compensate for external ports right? You need proof you are using the software in a knowledgeable way, otherwise this video can be misleading.
Look closely and you'll see everything you asked for. There is no cabin gain simulation because the software can't do that, furthering the point being made. Even in free-air it's not accurate which was demonstrated in having two completely different response curves. As for external ports, the volume wasn't based on port displacement and therefore doesn't matter either. Plain and simple, those programs aren't accurate for how they're used. Put it in a car, or a room, or anything other than outdoors or an anechoeic chamber and it won't be right. These are things advanced audio people already know, but needed to be proven to the inexperienced that follow it to make purchases or do installations.
@@EMFAudio You can add the cabin gain to the software, this is what I do, on BBP you cand import the cabin response, or just input the longest measure of the cabin in feet, then convert that to Hz, then input that. So soy can get a simulation inside cabin, outside cabin. Port displacement is way too important, the BBP never consider a port outside the box, since you don't compensate for this, the simulations will be wrong. What Loss Factor you calculate for the ports? Otherwise i I use LEAP for designing, its a high end software for speaker, enclosure y xover design, you should take a look for it. The problem with software is mostly the user, what soft gives you is just a starting point.
@@electronicatotal6698 WinISD can't do it, and BBP will still be wrong. Simply putting in the length of the vehicle will not calculate cabin gain. There are 3 primary axis where waves reflect and they won't reflect equally so you can't even necessarily use those calculations unless it's a square or rectangle with perfectly flat sides. Additionally, because of EXPERIENCE, I can tell you the car will act differently at different SPL levels and the box will act differently at different power levels because the sub acts differently because all those parameters you entered are based on small signal, not large signal. When all of the panels and metal start moving, everything changes. For this reason you can add deadener and change the cabin gains. You're changing the resonance of the panels and potentially stiffening them, further rendering any measurements useless. I'm familiar with LEAP, and I'd look to see how much it costs now but they appear to be out of business. Last I knew it was something like $1,600 which few will pay for, and it still doesn't cover all of the other dynamics I mentioned. It seems you're stuck on simulations must be correct because numbers say so, the reality is it would take a NASA budget to create something that could potentially accurately simulate it in combination with many many other tools to measure various parts of the car and how they respond to pressure and sound waves at various barometric, temperature, and humidity levels.
@@electronicatotal6698 If you get results that aren't correct when tested, they're wrong. I did it from actual data so nobody could say anything was rigged to show it wrong.
Jacob used to say the same thing, but it seems like more people have learned that TSP's can actually be used to accurately model the enclosure, and that cabin gain/loss isn't factored in to most programs. That in no way makes them wrong; this video is misleading just so that when people plug in the specs of drivers and see that they plot to sound horrible they disregard it and spend the money on terrible sounding drivers anyway. Also, the program you are demo'ing doe's not factor mh or le of the coil, which would lead to a difference in actual sound from the setup than shown on the plot, there are programs that are smart enough to factor Le, mH, air density, etc. Misleading the consumers to sale products is a terrible thing.
Both pieces of software do take into account inductance, and some do take into consideration temperature (though it defaults to room temperature usually). If you actually watched the video you'd see that both programs say different things, regardless of what the reality is. That inherently means at least one of them is definitively wrong.
I have to disagree, uour testing is inside of a vehicle ,although open, it still has an effect as well as you are inside of a building that also has an effect. Bass Box Pro is pretty good with the accessories that permits the system check and cabin gain which I use to design my enclosures. with this program this program has a acoustic section that allows the aciustics to be saved to help predict its performance...it also has a option to add a impedance reader that will save you a lot of headaches in controdicting parameters....without these devices...you are just guessing at its output and performance. in closing, don't just get tge program, get the accessories that allows tge program to do what it was designed to do.
If you have all the extra tools, you don't need the program. Also, as the environment is a factor, all that data you plug in becomes invalid as SPL increases. It's true, RTA a car at 100 dB, then 120 dB, then 140 dB, then 160 dB and you'll find everything changes.
I see so many comments here talking about cabin gain, or how the software is meant to simulate in an open space. So many people here think they're smart, but are honestly just an echo chamber for one or two main criticisms of the video. There's plenty of sources here on RU-vid that go over various audio topics on the engineering side, and with a bit of applied logic, will show why adding just the variable of cabin gain won't make simulations much more accurate. Peter Kulicki from HexiBase and Audio Dynamics has some good content on this kind of stuff. Explaining how car and home audio work outside of the speaker enclosure, how box and port geometry changes output, etc. Just knowing that geometry of chambers can change output should tell you that just applying the variable of cabin gain isn't enough, especially considering a vehicle has geometry that's very impractical to measure. Then you get into how materials reflect and absorb sound, or inductive losses through panel compliance and how energy travels through panels that're fastened together. If everyone could just do some more research and use some logic, maybe RU-vid wouldn't be an echo chamber of idiocy. And even then, an outdoor PA system will have the most accurate models, but even then nothing is perfect, and there's still variables you can't account for.
But you're learning inaccurate information. I like a lot of his videos and was disappointed to see this one. He is wrong in his assertions and a real tech stuff Tuesday should go over the proper way to correctly use the software. Instead he bashes the software because he is using it incorrectly.
I used to race karts alot and a guy told me i gotta quit beating myself,that my friend is what emf seems to be doing bc as a newbie hes talking way the fuck over my head..
Lol your win ISD parameters are wrong. 2 seconds of looking at your curve plummet after your peak makes it pretty obvious. Only a couple reasons it does that. Can you show the settings you have.
The parameters I took directly off the subs themselves are wrong? The Qts is why the curve plummets in the graph and funny enough, not in the car. I'll remind you, both programs estimate something different, which automatically means one of them is wrong.
very biased video and title of course the software can not compensate for the cars resonant frequency . the software calculates the frequency response in free air and as such gives a pretty good estimate of how the subwoofer will respond in that specific scenario . however when you put that same box in your car you have basically created a bandpass an enclosure in an enclosure . repeat the same test with a window open or slightly open and and it will also change the output significantly . In my 2 decades of building subs i have found that small cars like yours usually get a peak or boost around 60 hz sedans around 50 and really big cars like suvs around 40 . But we usually do test this with a sub that has a very flat response . And then we use the software to create a subwoofer that compliments the car . These clickbaity titles and videos DO NOT help anyone and you know it why else would you write in the video description Quote :"Purchase your car audio from www emfcaraudio com and get our expertise too." That is as shady as it gets basically saying only we have the expertise , those programs are garbage . But looking at the other comments most people see right through your BS . If you had any integrity you would NOT just shit on the programs but use this opportunity to educate people how to use them properly
Nothing clickbait about it, the problem I see is you already knew what the video explained. Not everybody knows what you know. There are people that swear by these programs and think that's the result they'll get in car. The proper way to use those programs is to not use them for anything other than port calculations of figuring out volume quickly when changing dimensions.
I get what youre saying but your overall point seems incorrect. The calculated frequencies are not necessarily incorrect, they just don't consider the variables at play in a car. Yeah the software says the longer port would be quieter, but you've taken up more room in the cabin and moved the exit of the port so it's not and cannot be a fair A-B test
It sounds like you're making excuses. You think a miniscule difference in car displacement is the difference? If that were the case, me being in the car would over a few dB difference. The fact is, even if you take out the environmental variables you said, it's still wrong. In free air, it would still be wrong.
@@EMFAudio I was giving examples of variables you have changed. Yes the cabin volume change is likely insignificant, but moving the port opening 6" further from the drivers and closer to the rear of the car isn't. If you used actual measured ts parameters for your drivers and performed the measurement in an anechoic chamber, like the software is assuming, it would be accurate.
@@cncgeneral The distance on the port doesn't change anything in that car, I've tested it. I did use the actual tested parameters, and you just proved my point. ZERO people are listening in an anechoic chamber. Literally zero. There is no application where you would be doing that. But don't worry, I have another video coming in the future to prove everybody wrong stating it would be right outside of the car. Then there will be a new series of excuses to address.
@@EMFAudio Exactly, I'm not disputing that the calculated response will not be correct in a car. Just that it doesn't mean what is said is wrong either. Physics is what it is. If you use a fluid dynamics simulator and modelled it all exactly, including position of the box, port speaker, seats, car body, materials used, etc. You'd get pretty close to real values. In reality, I don't think anyone is using box calculation software to try to predict spl in their cars, it's used to check tuning frequency to avoid over excursion. For that it is more than accurate enough. Finally, you say no-one is listening in an anechoic chamber, that is fair, but your BBP calculation includes a measured frequency response, if that wasn't measured in an anechoic chamber then your graphs will never be correct as they'll include the response of the room they were measured in.
This video is pointless and your view that modeling software is wrong is way off base. If you want the modeling software to be closer to actual in car measurements you need to create a frequency response graph of a speaker in open air and an in vehicle response graph using that same speaker. Comparing the two graphs will give you the data you need to create a room response graph. You can then create filters in WinISD to simulate the in vehicle response. PS: Anyone who has a reasonable understanding of how sound is influenced by room acoustics will be very turned off by this video and be very unlikely to patronize your business since it makes you look less than well informed.
@@EMFAudio Do you know of Chad Geary? Someone recommend him to me for the SPL (burps only) build I want to do. The thing is that he works for somebody else so I will need to deal with the owner.
