JohnnyRock1588

iTrader: (22)

Hey guys I'm starting my spring build on my 2005 nissan altima 3.5se
I've been in car audio around 6 years and heard a lot of different sub set ups from 8's to 15's ect. Ever since i got bit by the car audio bug i just cant stop as sound really intrigues me and I love music! I've though long and hard about this build and i want it to be special. I have never heard an Infinite baffle set up but am really curious as to how the work and how they are built and if i can do this myself. which I don't see why i couldn't but thats why im here asking questions. ANY and all input about this build and mainly regarding the IB set up will be greatly appeciated. This build Is going to be sq oriented that will get crazy low and loud when i want it to! I'm hoping with the suggestions and help ? I receive from this thread I can start building and update as I go a long and eventually have a finished product to display for everyones hard work and input!

My current audio list:

Eclipse 7200 mkii
HERTZ MLK
JBL Co8 gti mkii 6.5's
Zapco DC ref 360.4
Phoenix Gold Titanium 1000.2 A/B
JBL GTI MKII 15'S
1/0 ofc all round

Forgot to mention I will be looking for a 2-2.5 k amp that will be able to give the JBLS a serious workout. I'm selling my titanium 1000.2 if anyone is interested but for now thats all I have for a sub amp even though its not going to run at 1.5ohm I could always use it on one or just wait until the amp is sold to fund a new amp. What do you guys suggest for amps? I was thinking sundown 2500 or something a long those lines

fozzz

iTrader: (1)

Pretty much any sub will work IB. The real question is what response you're looking for. Most people choose IB subs with a high Qts. Depending on who you talk to, a Qts of .707 is the ideal number. But it really depends on the listener.

JohnnyRock1588

iTrader: (22)

John! You were the one that suggested I go IB!! Tell me more as to how I accomplish it successfully also need more power! The response I'm looking for will be relitively loud by most "sq" standards. Almost bridging into spl territory. I love my low end! My goals primarily will be sound but I want the 15s to get louddd. I know I can't fit a large ported box in my trunk so that's out the window.

fozzz

iTrader: (1)

In my opinion, the JBL Gti 15 is about as good as it gets for IB in a car. It has a high Qts, which I prefer in IB subs, so it well controlled. The sub will play low and can take a ton of power. I can't find anything wrong with the GTi. I even like it's looks. It is huge, but most 15's are generally big, so that shouldn't be a problem.

JohnnyRock1588

iTrader: (22)

I agree. What do you think about power and any suggestions on an amp to power the two?im also gunna need some help with this build doing the ib set up as I have never built one before.

Dukk

A high Qts value means the driver has less control of the cone. This results in a speaker that needs a large box to have good low frequency response which is desireable for an IB driver.

There have been examples of IB drivers with very low Qts values. In these cases the driver has maximum control over the cone and essentially forces the speaker to behave in a consistent manner almost independent of the box volume. Not many (any) of these drivers around these days.

fozzz

iTrader: (1)

I should say, have the appropriate amount of control for it's given enclosure. A high Qts sub requires less "spring effect" from an enclosure. When you design an enclosure you usually work around a desired "q". Most consider .7 to be the ideal response (2 nd order Butterworth response). This gives to a low cut off and a generally flat response in the passband.

One of the reasons low Qts woofer were made was to allow them to work in very small sealed boxes. A small enclosure will raise the system Q, which combines to create the desired .7 many look for.

Cabin gain has a huge effect on this, so other factors need to be taken into account.

ryls

iTrader: (1)

Ive been debating on trying an IB setup in my impala to get a much smoother response curve. Im content with the volume of 1 12 ported but the drop off above tuned freq is huge and i want it to play low enough so tuning high isnt an option either.. Also how does the trunks internal volume relate as a box? Like i mean seeing as there not run true IB and your trunk is basically a box im assuming there are some kinda quidleines? Like would my trunk have the volume to run 2 15's IB? Im pretty sure i can get em in if there not to deep.

One thing im pretty sure of is that to keep the same kinda volume as my 1 12 ported im going to need to run 2 subs IB.

sorry if i took thread off topic

Dukk

At 3x Vas the box (trunk) has sufficiently little effect on response that it can be considered IB. At 10x Vas the box (trunk) has virtually no effect on response.

For a pair of 15s the trunk of most sedans is really just a big sealed box. How well sealed depends on the installer.

JohnnyRock1588

iTrader: (22)

with that being said dukk about sealing, how do i go about constructing and sealing porperly? what kind of adhesives and sealants to use? double 1" baffle? i havent come across a great build log to really learn how to achieve what im looking for. im looking more about the actual construction of ib.