I am putting together a system, and i hear the pro's and con's of each box. My questions is a two part question, the first one is: seeing that a sealed box is more for sq, and covers a wide wavelengths, and the vented box is louder but does not do well in many of the wavelengths or you might call it hz. why not do one side sealed and one side vented 12"S ? is there a reason why it would not blend like a two way sub box? and if it is posiable would two mono amps be better then one amp the yields the same wattage?

that is referred to as 4th order bandpass

1 amp is better than 2 generally. If one of two goes down, you may have problems. If just the one goes down, nothing else can happen...

what kind of sq does that set-up produce? here where I'm at i put together my highs and mids first which consist of Morel ELATE 5 3W - Morel 3 Way Component System in the front, and the 5 1/4 elate in the rear, but i went with the cdt200z and 300cc crossovers, and a four channel arc audio 4150 cxlr amp, and now I'm on this sub thing, i want to sound loud when i want it to, but also want that tight sq bass when I'm with girl friend you know what i mean. Thanks for your time

Edited July 16, 200817 yr by hobbydepot101

i'll let someone else comment on bandpass designs. I have little experience with them and can tell you bandpass designs are terrible for sound quality.

2nd, if u have ran sealed before, going ported is a higher efficient box design so it will be louder.

In my experience, building a ported box using the least recommended internal box volume yields better sq than the largest box recommended.

I do not know why so i may be stating this just for a certain install i did... I just know when i have used large boxes for a single sub, the overall sound is very loose and muddy. This new install i did, i built the box smaller and it sounds incredible. I run 2 cubes per 12 when i should be running 2.5 cubes per 12. I am not lacking on the low end whatsoever... i have people to verify that as well

I am tuned to peak at 34hz and can drop below 30hz easy.

EDIT - I do know that the larger the box, the higher the group delay which is bad. This may be why my current install sounds better, "tighter" as you would refer to it.

thanks for that info, thats what i wanted to hear, i plan on using two re audio shallow mount or jl audio's new one, or critical mass, or illusion audio nd12i can you help me narrow that down to one

Edited July 16, 200817 yr by hobbydepot101

So you're running a Morel 3-way set but using CDT passive crossovers?

Eh...problem #1 there. Setting up a three-way set is not a task for someone getting into this kind of thing.

my mids and high are great! not a problem there, and the cdt crossovers are more flexible and sound 5times better then the morel xovers, i chose to go passive because all of the electronic xovers that i have looked at did not have better numbers as far s/n and thd then the amp and the drz9255 that i am using, and we all know that your system is only going to produce the highest amount of hd that is link in the systems path. but these are my ears and i have to do what sounds good to me, even though i have had great feedback from some experts in my aera.

S/N and THD are not the magic numbers some make them out to be, and in addition I'd rather have a setup that measures worse but has the proper Xover slopes and points than one that has amazing S/N and THD values but is set up wrong But you're right, it's your ears so I don't know what you're hearing

what is so hard about slopes that the manufacture give to you? woofer 20- 2600hz mid 450-7000 highs 1400- 2500, and a lot of room to play with. so i do not see the e=mc2 problem. but maybe its that you are not familiar with these crossovers and morel, and dzr9255 or arc audio cxlr

its not rocket science

Didnt JL do a sealed/ported box in one of the mini versions (#2 I think)?

IIRC they had use linear actuators to open and close a flap over the port opening.

Something I always wanted to try out, just never had the money to just experiment with it.

thanks for that info, thats what i wanted to hear, i plan on using two re audio shallow mount or jl audio's new one, or critical mass, or illusion audio nd12i can you help me narrow that down to one

The JL Audio TW5 is an amazing woofer, it is 2.5 inches Deep and 600 RMS on the 13.5". It has to be run in a sealed box though, not recommended for ported. Just think about what shallow woofers were made for, saving space. Ported boxes don't save space, they are too big.

http://www.criticalmassaudio.com/catalog/i...amp;productId=3

http://www.audiojunkies.com/blog/646/res-n...nclosed-woofers

http://mobile.jlaudio.com/products_subs_pa...php?page_id=245

http://www.illusionaudio.com/docs/carbon_subs.htm

If you chose to use another manufacturer's passive crossover over the 3-way set manufacturer's crossover just because of S/N and THD, you went about it the wrong way. I dare you to hear a difference in those in your setup. Not to mention that don't you think the speaker's manufacturer knows a little more about their own speakers and sets up the crossovers to work the best with them? Slope is not everything, neither is having a lot of leeway in where to place the crossover points just because the manufacturer gives a large range of frequencies each speaker can play. More of it is about where to put the crossover points so that the speakers work well together.

You have a 9255 but are using passives??? *PUKES*

First off the ones you have selected DO NOT work with your drivers. Huge problem, has to sound like crap.

Also, you talk about SQ so why do you even care about a ported box. What you described in your first post is not a bandpass, but two separate enclosures for two different drivers which is also a terrible idea. I don't understand what you are trying to accomplish. Sealed boxes can do everything that a ported one can, albeit at slightly lower levels but in the case of blending with your front stage the levels will not be the problem.

Do yourself a favor, quickly throw away those crap passives and use the 9255. Put your subs in sealed only enclosures and sell your rear speakers as they are doing nothing good for you either.

It sounds to me like you have been very, very misinformed by the marketing machines. You bought all this nice equipment, but missed out on the fundamental that the install is WAY more important than the gear and currently yours is confused.

Your answer sounds logical, true electronic xovers will give me more flexibility, but believe it or not the system sounds very nice, but can be better i know, now the question that i have is if i use e/xovers on a three way system, i would need a amp out to each componet right/ so i would need 6 channels?

Yes, 6 channels of amplification on a 3-way active system.

you know what, i will give it a try, if i sell the crossovers that i have which cost me $600 for the two pair that should be enough to get a decent electronic xover, but i do wonder why all components, and even home audio comes with passive, and why are passive xovers so expensive if no one are buying them?. but you r right the 9255 is design to use e/xovers. thanks and i will let you know the end result.

http://www.woofersetc.com/index.cfm?fuseac...Product_ID=4523

http://www.woofersetc.com/index.cfm?fuseac...Product_ID=1282

here are the two sets of xovers that i am working with. i will give them up and try electronic crossovers, so at lease i will be able to compare for myself

You're not fully understanding here.

Passive crossovers are specifically matched to certain drivers. You cannot simply take any drive and slap it onto a prebuilt crossover.

Your 9255 has crossovers in it already, you don't need to buy anything other than 6 channels of amplification.

Indeed the only reason to run the 9255 is the built in crossovers.

For passives to work, the drivers need to be measured in situ and they MUST be custom designed not only for the drivers but also the environment.

All you need are amps and to get rid of the rears, as they do all sorts of bad to your sound stage.

Again blend it with a sealed sub and get ready to smile

thanks i will start buying the extra stuff i need, one more question i am going to buy another of the same amp, which is a arc audio cxlr 4150 now that will give me a total of 8ch i need only 6ch should i bridge that amp into 2ch/ and if so put that 328watts per channel where? i want to make full use of both amps

that's a lot of power. I doubt any of your speakers can handle that much. But if you felt the absolute need to do so, do it on the woofers. They are generally not only the least efficient but are also able to handle the most power because of their larger motors and coils.

thats sounds good seeing that the 9" thats in the door can handle 200watts Continuous and a 1000 max. we will see what happens http://www.woofersetc.com/index.cfm?fuseac...Product_ID=4780