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jfrost89
03-29-2012, 08:42 AM
I have 2 solo x 12s that are going to be ran off 2 kicker 2500s my box is going to be roughly 8.5 cu ft before displacement I want to tune it to 32 hz using 4" aeroports. The question is how many do I need and at what length these are going to be external ports coming out the top of the box with subs facing forward.

Flastrongman
03-29-2012, 08:49 AM
A LOT if you're stuck on 4". You'd be much better off running a couple 8" or 9" aero's.

jfrost89
03-29-2012, 10:03 AM
I could do thast to. What your thoughts?

Flastrongman
03-29-2012, 10:47 AM
Well I ran 2 9" ports for my 8cu box and cover 1 up for daily tuning.

jfrost89
03-29-2012, 03:55 PM
Well I ran 2 9" ports for my 8cu box and cover 1 up for daily tuning.

Oh yeah I bought your amp lol im about to start my box but Ive never used areos before how long do you think they should be and what tuning would that be?

kramer_212
03-29-2012, 04:04 PM
Well I ran 2 9" ports for my 8cu box and cover 1 up for daily tuning.

oh i was going to say 1 10 or 2 8s, but depends on what your after.

Flastrongman
03-29-2012, 04:33 PM
I had the box tuned to 39hz with both ports open and 29hz with 1 open.

Moble Enclosurs
03-29-2012, 05:19 PM
Just be careful with the multiple tuning ideas. It can backfire if the design gets smaller, because it will rely more on other factors to control output response. One may end up being much different than the other and can be unsatisfying if your sensitive to changes in audio. Its likely that most designs that are built that way do not account for proper characteristics of both ideas for tuning. But it is also more common that people are forgiving to these changes as well.
Just a thought for you if you want it done right, there is a better way for multituning.
As far as port area, send me an email or pm and I can get an exact area needed for the sub(s) mentioned. If you want more opinions, and other facts also that can help tremendously.

Flastrongman
03-29-2012, 05:41 PM
Just be careful with the multiple tuning ideas. It can backfire if the design gets smaller, because it will rely more on other factors to control output response. One may end up being much different than the other and can be unsatisfying if your sensitive to changes in audio. Its likely that most designs that are built that way do not account for proper characteristics of both ideas for tuning. But it is also more common that people are forgiving to these changes as well.
Just a thought for you if you want it done right, there is a better way for multituning.
As far as port area, send me an email or pm and I can get an exact area needed for the sub(s) mentioned. If you want more opinions, and other facts also that can help tremendously.

Well that sure seems like a nice way of telling me I did not know what the hell I was doing or was just guessing at the design for my last box.

Moble Enclosurs
03-29-2012, 09:08 PM
Well that sure seems like a nice way of telling me I did not know what the hell I was doing or was just guessing at the design for my last box.

If that is how you feel, I don't know what to tell you. If you are offended by someone else with experience giving help, either constructive or instructive, then that is a personal problem of your own. I am not telling anyone you do not know what you are doing. I am pointing out cautious possibilities of doing something like that because they do exist. There is no personal reference to you. Is that understood?
If I want to reference you, or your work, I will quote you. My message was not quoted was it? Therefore, it had nothing to do with your knowledge or work. I do not know what design you did, nor how you created it, so I cannot and will not judge it without knowledge. It was not personal, and if it offended you, then you need to refocus the reason of why you were offended.

My point was, if you are to utilize such an idea, make sure it is correct because phase issues and other things will cause adverse effects in a lot of cases and a general listener may not pick up on the discrepancies. Simple as that. Understood?

Loudmp5
03-29-2012, 09:27 PM
Lol sounded like he might have been joking about that post but if not good way to handle things:fro:

Moble Enclosurs
03-29-2012, 09:43 PM
Well, I thought the same thing at first until the defense went up. Because normally, in a conventional design (where phase response is less sensitive), the parameters of the design will change and can be dramatic if done with multiple tuning without a removal of the displacement of the other port. Excrusion, phase, and timing effects will change, where the one with a higher tuning may be designed secondary to the lower tuning one to achieve at least a somewhat usable response down to the low 30s.
Essentially, to pull that off effectively (meaning with maintaining acoustic efficiency and output) without losing something of either one tuning idea, you would need to figure for those effects, and I know it can get complicated as far as the calculations go, unless you decide to rely on a program to do it for you, which I do not know of one that can....that I am aware of.
That is all the reason why I mentioned what I did. Because depending on what tuning you use, and what volume, placement, etc..all factors of the design, to pull that off with optimized output (not considering what one would consider just "usable" and "good enough"), then that can take some cautious planning and designing to achieve.
I have seen many times, others try to make a design with multiple ports, even with those that are removable, with sad results. And even some with usable results, but not one that has had both outputs equal in authority and passband response that was considered optimal. One will have a higher degree of distortion, and one will control the drivers excursion better.
ALl I was trying to say, was it can get pretty involved if you want it done right, so know how to do it and you will find yourself with great results.
Im not sure how that is offending anyone. Hmmmmm :D

jfrost89
03-30-2012, 01:46 AM
Come on guys theres no need to get all up in arms about box building I just need some ideas on what size ports, how long, and how many. I really didn't think it was going to cause a bunch of problems lol im sure you've both made plenty of boxes and good sounding systems so im just looking for some suggestions. Ive built alot of boxes just never used aeros and wanted to try something different.

Moble Enclosurs
03-30-2012, 02:01 AM
No problem. I do apologize on my part for a lengthy explanation and rebuttal. Our focus is for you. Now, I cant give you that information right now to help because I am at work, but if you want to send me an email or pm with the driver information and dimensions you wanted to use etc, along with the information listed on this thread, I can look into figuring for a proper port area and such with my own calculations. If not, I'm sure someone may be able to give a more generalized response that may be fitting to your request. Either way, I hope we are able to help you soon.

Flastrongman
03-30-2012, 06:59 AM
Just be careful with the multiple tuning ideas. It can backfire if the design gets smaller, because it will rely more on other factors to control output response. One may end up being much different than the other and can be unsatisfying if your sensitive to changes in audio. Its likely that most designs that are built that way do not account for proper characteristics of both ideas for tuning. But it is also more common that people are forgiving to these changes as well.
Just a thought for you if you want it done right, there is a better way for multituning.
As far as port area, send me an email or pm and I can get an exact area needed for the sub(s) mentioned. If you want more opinions, and other facts also that can help tremendously.

Please enlighten.

Moble Enclosurs
03-30-2012, 09:27 PM
Please enlighten.

Well, what can happen is this:
The normal way that people follow a multi tuning enclosure for say, daily and spl use combined, is by creating two different ports with different characteristics, without changing the compression area much other than added displacement. So, when you have a port area that is constant, such as a round or aero port, you have a specific tuning that takes place. In other more complex designs, there are other effects that are much more important than tuning. Those are coupling and control of the response curve within a passband rather than a reliable tuning with a general cutoff.
SO, take this for example......you have a conventional ported design with two round ports, as stated by you above. With the port area of both combined and the length of those as another constant, you create a specific response curve that is not changed. Therefore you think that by covering a port, you will only merely change the tuning and passband of that previous response, but you can create problems. The main problem is that when a lot of designers create enclosures, they pay too much attention to the only curve they present to the clients, which is the response curve. But less attention is payed to other factors of the design, and some designers do not even pay attention to them at all. Those factors are either known or unknown. I will not go over them if you are unaware of them all.
Now, regarding that and covering the port, those changes will occur and they will either help or hurt the situation. When those other factors of the enclosure are considered, which they have to be, then they present changes with the response curve that are not shown in a normal calculated response. THESE HAVE TO BE CHANGED MANUALLY, which a computer program is not yet capable of. Not even hornresp. So, these changes have to be considered. I use 3 different programs that I combined to create the response I show the clients and it includes the changes that occur with the other factors.
So, by covering up a port, you can change one of those major factors, which is in fact the phase response. That one I will mention. ANd this may end up giving other designers the ability to create better or more accurate products, because the phase response is VERY IMPORTANT in the overall output of the design. If you have a design that is tuned to say 38Hz, and the response curve shows it goes down with a -3dB response to about 34Hz, for example, you will want to say that this design is capable of going down to 34Hz efficiently, but can go further below that. And that depends on the phase. If you have a normal conventional design with those 2 ports and cover one up, that changes the phase and not only that, will also change the port characteristics by cutting the volume in half, but not effecting the length. SO, for this, most designers will create ports with different lengths to create a different tuning. But this is not the case with your mentioned situation, but it definitely should be because that length change will and can balance out the phase response that is needed to keep the design operating within its calculated response curve efficiently, WITHOUT having to turn up the volume to compensate.

So, what you can create, and is not always true but as mentioned, a possibility if not done correctly, is an out of phase response just by closing a port and changing nothing else. You do have the chance to mess things up, but you can also have one that only helps the phase IF you designed it originally using a higher tuning and then created a lower tuning, which covering one port is capable of doing. SO, granted, it can work, but you still have to know how to figure for it, or else you just get lucky. There are no other options to it. either luck, or know what you are doing to the design. Pretty simple .
So, say you have a phase with a usable response from 1-242Hz. The driver specifications will provide a more broadband output along with subsonic filters, and low pass filters, but calculated you can have a HUGE response range, even above the nominal 1.5 octaves of a normal sub frequency system. So in other words, you can have a design that goes up to 120Hz or 80Hz, and still goes subsonic, just with lost output with a given slope, which is not natural....its based on the setting of the system. naturally, with a given 0dB capability with no losses, it is possible to get more out of that response, but naturally sub amps do not allow it due to excursion limitations as well, which is a major factor is lost dB levels below tuning. Above tuning, lost dB has a major factor of distance from the source.
Now, from that 1-242Hz range, you get a response phase that allows that to be used by the sub with the given mechanical limitations and resonacnes that get in the way. So, you end up with an efficient response from say 27-60Hz or whatever the design allows. This can be calculated and is not shown on a response curve.
NOW, say you cover a port up. You change the characteristics of that port. Thus changing the phase and output passband and essentially everything by its own factor of dominance and importance. Thus creating a different "tuning" and a different usable range. BUT, now you have to look at that range within the phase correlation of the entire response curve and then figure for what is usable then.
You can have, in a worse case scenario, and out of phase band that starts in the mid 30s and smooths out as the frequency increases. So, this is usually caused by covering up a port without accounting for specific factors of phase and tuning effects, and just relying on the lower tuning shown in the respond curve and saying, "I have two different tunings for my box". You can then narrowband the response range to something that has a higher rolloff rate at the lower end of the response curve, around the mid 30s, and lose more output below that based on covering the port ALONE. Not by any other change. ANd then have a higher efficiency as the frequency increases EVEN THOUGH by having the port area smaller, it should lower tuning, because tuning has no major effect on the response that you hear. And then that higher efficiency from the higher frequencies will still be faded because of the natural bandpass of the amplifier, so you have a constant output level there. SO, what happens, or what could happen, is you just lost lower end output by lowering the tuning! Sounds backwards, BUT completely possible.

Now, if you get into some other factors, which I said I would not mention, but one is already well known as well as phase, which is excursion limits and control. This changes as well. You can effect the output by changing that as well. So, where you once has a tuning with a low xmax when loaded, you now have a lower tuning with a peak at the previous tuning with an excursion factor that can exceed the maximum excursion of the drivers limitations! So, though you can tune and play lower(as long as you don't mess the phase up) you then have the possibility of blowing the sub mechanically due to overexcursion at a higher frequency! Again, one always thinks, " as frequency increases, xmax decreases". Generally yes, but in a conventional design you always have a peak excursion above tuning before it drops again! This should be known by anyone that figures for that as well.

I am sorry if this may be jumping around a lot, but it is easy to get confused when trying to explain everything that can occur without actually getting too detailed. because everything is effected. And if you do not understand what happens just by simple covering a port, then you have the change of things not working right or even causing damage if you are using max power levels all the time, which a lot of people do instead of getting a more efficient setup.

Now, I do not know if this explains a better way to do it, but it give you an insight on what to look for when doing it, which in turn makes it more accurate and safer to do. Keep in mind that this does not always occur! It can occur more often than not, and damage may not even be an issue in some cases due to proper power leeks being utilized, but still why take the chance when you can do it right the first time?

There was someone that came to me recently with a design from a very reputable designer, which I will respectfully remain anonymous, an=bout just this concept. I looked over the idea, and behold!....it had many issues with one of the ports not having the capability to provide the output within its "calculated" range of operation because no consideration was made to make sure it was correct. This is the exact reason why people say calculated is not as good as real world, when it comes to things like bandpasses and such...because the knowledge of this and how to control it is limited in the audio community. Even with a knowledge of its existence, meaning the factors mentioned, you still have to know how to account for them correctly.
And tell you the truth, by making a design with two ports and covering one up, you have a higher possibility to create a design that will be less optimized for the subs and the environment, though it can still play well, and be acceptable, it can be much improved at the same time.
I hope that helps you understand more of what I meant and I hope it helps the other designers to open up their capabilities of what can be accomplished and what it can take to make it right. This is not saying they do not already, but it can be shown in the work done if you pay attention to it.
It is not hard to make a design sound great. That is actually the simple part. Because since there are so many types of sounds that can be accomplished, the range of getting it right is great and the ear is very lenient to something that makes noise vs something that makes sound.

Flastrongman
03-31-2012, 10:23 AM
LOL all that time you spent typing I was building...

Under Pressure
03-31-2012, 10:42 AM
I hate when people do that. Just state your opinion and move on. You told the op you would need to do calculations and such. Then wrote this long *** 2-3 posts.

I wonder would you need a program to make that design? Is that why the numbers cant be done right now?

Although i dont have an enclosure built by Fla i can tell you this he needs no advertisment or youtube page to get his work its all word of mouth. The mans a genius and a craftsman. He specializes in squeezing huge numbers out of subs that you would probably laugh at.

My point being that if you want to respond to someone without a big fuss. Climb off your high horse stop making walls of text and simpley state what you think without trying to sound so smart.

Please dont take offense its just how i see it.

mojo1
03-31-2012, 10:52 AM
^^^ x2 Flastrongman is a great builder seen his work and everything. Great builder there i'd take his word.

eutechnyx
03-31-2012, 11:09 AM
This thread delivers....Fla ftmfw.

mobeious
03-31-2012, 11:43 AM
Its as simple as this ... u have 2 ports to raise tuning and 1 port to lower tuning if u take into consideration the amount of volume the port displaces the only side effect to this would be port resonance which would still be too high in both cases to effect the subwoofer

Flastrongman
03-31-2012, 01:10 PM
Its as simple as this ... u have 2 ports to raise tuning and 1 port to lower tuning if u take into consideration the amount of volume the port displaces the only side effect to this would be port resonance which would still be too high in both cases to effect the subwoofer

WRONG!!!

I'm not sure why you're wrong but I know you can't be right. Here's why:

1. Your response made sense
2. It was simplistic and easy for everyone to follow
3. (This being the most important reason why you must be wrong), you responded with 1 sentence. Are you serious? Come back after you've written at least a full page of nonsensical ramble and maybe the god of car audio will acknowledge your existence.

NT_Hardcore
03-31-2012, 01:13 PM
i just wanted to post in here, carry on-

BlactimusCrime
03-31-2012, 01:14 PM
WRONG!!!

I'm not sure why you're wrong but I know you can't be right. Here's why:

1. Your response made sense
2. It was simplistic and easy for everyone to follow
3. (This being the most important reason why you must be wrong), you responded with 1 sentence. Are you serious? Come back after you've written at least a full page of nonsensical ramble and maybe the god of car audio will acknowledge your existence.

I lol'd

Moble Enclosurs
03-31-2012, 02:58 PM
I noticed I have been getting attacked in here quite a bit. And I would hope your biased attitudes would take my posts as help. Either way, Im sorry that you don't understand what I am saying, and I hope that you are doing well in what you create. No one has said you are doing anything wrong, so the defense is still confusing. There are only two reasons why you would still attack my posts, and that is 1. you have no clue what Im talking about, 2. you have to defend yourself because you may be wrong about certain things. Either way, I noticed that the first 4 people are from florida. How ironic. But to each their own as they say. I am not mad or upset any anyone nor have I said anything about your personal work or your relationship with your friends or customers. That is not how a man reacts to business relations unless they feel threatened. And that is not my purpose at all. In fact, I have visited your site as well, and I have to say, great work! Looks like some great stuff you do. And I do hope you continue to do great in the future because it does seem like you have a group to always follow, and that can be needed in the audio business and is very common. Me, I am here for everyone and I try to help everyone. I do not have a local clan or an internet clan of nut huggers, which is perfectly ok. That just means they trust what you do and that my friend is very respectable.
But what I do not respect is how you try to maintain your business, by trashing on others. That is pretty childish if anything. Though I have to admit, the remarks were pretty amusing and its easy to see how people will say here that you are pawning FTMFW, and things like that. I won't argue that what I typed was long. but I do hope people get some use out of it. And if not, then at least they still have me to make it easier for them in the future.
Again, I don't understand why you are upset and threatened. But, I can't control your attitude on here anyhow, so the only thing I can do is listen and hopefully get your mind to understand that my posts were meant to be helpful and it is as simple as that. When someone gets that upset about help, to me that says you are uncomfortable about something. And I would hope not.
The remarks about me needing to advertise....that is a part of running a business. Marketing and advertising are standard ways to get people to know what you are about and how well you can do with your work. That is why I have the Facebook, website, and youtube. I will not s hit on the fact that you have a website either. Because that is what you do to gain recognition that is not local.
I have had clients from many places of advertising and word of mouth on the internet because that is what my business is based on. I do not do local things yet, because I have to work out taxes and commercial property ownerships, etc. That I do not need right now. My success thus far is working very well to those who give me a chance to work for them and gig ether great products. And as a professional, I will not go that low and crap on your work.

And other than that, it is pretty simple. there is no quarrel I have with any of you. I don't do anything but provide great products, and service as well as very informative posts that a lot of people who are respectable, enjoy that I take the time to make it worth reading. It is those that get lost in the words that have problems, and if you cannot understand what I say, that is not a fault of mine.

I am not simple when it comes to designing. Im sure a lot of people here know that. Some hate it, some prefer it. That is out of my control. But at least I try to help when possible and I do not crap on other designers work without some constructive criticism, which seems like you cannot handle very well. Nor can your possy of florida riders.
Thats pretty much the gist if it right now. You are upset that I pointed flaws out to make the process better for those who are interested, and you have friends that ironically live in the same area that know you and will back you up on anything you say. That is not a problem at all. Just wondering why the hate on me. But as the saying goes, haters gonna hate right? I can't change your feelings about me or anyone else. But I do hope in the future, you will come to respect me as much as I respect you as a businessperson. Im sorry you are so upset and you needed others to defend you in this thread. There was nothing to defend but good that you have that i guess. :D Pm me if you wanna talk more personally about why you are so upset. I would like to try to work things out with you and your friends because I personally have not attacked you at all and do not plan to do it in the future. I tell the truth, and I try to help. Its simple for me and it works. Let me know what you think please!

Moble Enclosurs
03-31-2012, 03:02 PM
I hate when people do that. Just state your opinion and move on. You told the op you would need to do calculations and such. Then wrote this long *** 2-3 posts.

I wonder would you need a program to make that design? Is that why the numbers cant be done right now?

Although i dont have an enclosure built by Fla i can tell you this he needs no advertisment or youtube page to get his work its all word of mouth. The mans a genius and a craftsman. He specializes in squeezing huge numbers out of subs that you would probably laugh at.

My point being that if you want to respond to someone without a big fuss. Climb off your high horse stop making walls of text and simpley state what you think without trying to sound so smart.

Please dont take offense its just how i see it.

And I didn't take offense to that at all man. No worries. I see what you are saying and Im sorry if the post was too long for you to read. Seriously, that is not being sarcastic. But thats how I do things. I do not worry about what people think about it personally. I just try to be helpful is all. :D Im not upset at what you said. I respect it :D

Moble Enclosurs
03-31-2012, 03:33 PM
Simply put...I put a LOT of work into what I do and what I provide as outstanding customer service and wonderful products. I do not rely on work of mouth, I let it work for me. Half of my business comes from my website, which is not promoted on any other site than this one. I am not on any other forums where I advertise. I do very well with what I have been building since the beginning of 2008, and with the knowledge that I gained from my military service as a sound navigation technician and with my college work in electronics and acoustical engineering classes, which began over 12 years ago. I have been told many times to keep it simple. But I don't believe that will set me apart from anyone else. In fact, I am proud that I have so much to say. I am a one man show, and I am very happy with what I have accomplished thus far. And as far as computer programs to make it work, as mentioned above as an attack to me....no. I use excel for most of my rewritten calculations that I spent over 2 years putting together. Other things are used to present response graphs, but not for calculations. Because then, how could I be any different? I wouldn't be.
I am proud of what I do and I am not going to say its any better than anyone else. I am just very proud and feel great about what I provide is all. If you do great work, thats awesome! Seriously. No bad things to say. Just don't get scared of someone trying to say things can be done better, if they have the possibility of that. It is only to help. I promise. :D
And if I am ever wrong about anything in the future, I will take advice on someone who may be more experienced and learn from it. Not s hit on them.

Under Pressure
03-31-2012, 03:33 PM
Again for all your intelligence you miss the point. It isnt the fact that we cant read which you repeated several times in yet again another wall of text. Maybe people don't need the long drawn out explanation if they didn't ask for it? Whether you admit it or not your original post was offensive because FLA is a knowledgeable guy with loads of real world experience.
You did not stop to recognize that and offer your advice as a colleague, but as someone who portrays a superior attitude because you can spit 100 lines about the "science" of enclosure making.

At the end of the day you guys may have the same skills and both build awesome enclosures. But you never approached this situation like that. You felt as though your thoughts misconstrued.. they weren't we took it exactly like you wrote it... Condescending and arrogant.

Moble Enclosurs
03-31-2012, 03:52 PM
Again for all your intelligence you miss the point. It isnt the fact that we cant read which you repeated several times in yet again another wall of text. Maybe people don't need the long drawn out explanation if they didn't ask for it? Whether you admit it or not your original post was offensive because FLA is a knowledgeable guy with loads of real world experience.
You did not stop to recognize that and offer your advice as a colleague, but as someone who portrays a superior attitude because you can spit 100 lines about the "science" of enclosure making.

At the end of the day you guys may have the same skills and both build awesome enclosures. But you never approached this situation like that. You felt as though your thoughts misconstrued.. they weren't we took it exactly like you wrote it... Condescending and arrogant.


It must be mentioned that I have had good things to say about him in my posts as well, mainly because if you have people that are this passionate to back you up, then you must be doing a good job, I would imagine, even if a bias is there. Has that been noticed at all? Or are you going to just focus on the way it made you feel, vs the way it was really meant? Because there is a difference. The whole point is, if you felt threatened, there is a reason. And though you guys have crapped all over me on here, I do not feel that way. SO, what does that say about the other party? Just done feel so butthurt about it and things will be ok. You need to understand that the original post was not directed to him. That is as simple as it gets. And I did explain that before I was s hit on. Which if you are talking about being respectful, then why be disrespectful after the fact. It is very hypocritical if anything.

But, hey. Ill tell you what. FLA, I apologize if that did come off that way man. Really I am. I hope that you all understand that all I was trying to do was help. SO, if you took it offensive, please consider my apologies if you were threatened-for the rest of you as well. And Thanks Big for taking the time to explain it that way. That was very helpful! You seem like you have a good head on your shoulders.

Under Pressure
03-31-2012, 05:25 PM
i have nothing ill towards you from this, i was just trying to point that out. Now we can all move forward and make some loud noises.

My apologies if i came across like a jerk.

Moble Enclosurs
03-31-2012, 05:31 PM
i have nothing ill towards you from this, i was just trying to point that out. Now we can all move forward and make some loud noises.

My apologies if i came across like a jerk.

Word lol. Thanks for understanding BIG. ANd no worries man. I hope the rest of you are kewl too now, Seriously. I do like the work that FLA has done and HUGELY respect your guys' sticking by him. Says a lot about you guys. Very respectable! Now, back to work. lol. Later guys. :D