i currently have 2 12" alpine type r's in a sealed .85cf per sub box and i am not happy with the bass. i am running them at rms power. it does not hit lows very well, and it does not hit like it should with the doors closed. with the doors open it hits ok, but still not quite like it should. does anyone else have this problem? i am currently building a fiberglass ported box (to spec) and i am hoping this will fix it but wanted some other peoples feedback- will my new box fix this?

i want my system to hit when the doors are closed and want it to hit hard. !45db range. has anyone else had this problem of the doors having to be open for the subs to hit hard? thanks in advance...

 

You are going to need more than 2 Alpine 12's to do 145's on music.

The Type R is good for mid-upper bass and is a cheap, throw away burp sub to play around in the street classes.

 

that box is to small for them 12" you need a bigger box 1.5-2.0 cu ft for each them R's hit hard i have done over 5 different box's for R's each one sound very nice

 

That box is the exact reccomended volume by alpine. I dont feel like calculating the Qts but reccomended volumes are there for a reason.

Best thing if he wants to keep thoes subs is go ported. 145 on music is still an unattainable goal IMO.

 

+1 on that. You aren't moving enough air,...build bigger boxes.

 

Exactly i have alpine type r's but only 10s and i have them in a 3 cu ft box, sounds awesome almost blows the back window outta my truck, you can see it moving, and if its a sealed box you have itll sound like crap compared to a ported box

 

A shaking window is not almost blowing the back glass out. I have had the back wall of my truck hit the front of the bed...Over 2" of flex...It did not brake.

 

I hear what you're saying about the subs hitting harder with the doors open. I have one sealed 12" solobaric that's fed just over RMS- I'd swear it picks up 3db just by rolling down the windows or opening the doors, especially the passenger side.

Some people claim it's because we're dealing with relatively low power stuff, but gee wiz, I've got over 600w to one sub and you're probably talking about 1000w for those two Type R's. Granted the audio world is nuts, and I guess in the grand scheme of things, 1000w or less is not much bump. Then again whenever I think my stuff isn't "loud", I listen to some of my buddies' Wal-Mart builds!

A good ported box will likely help and pick up a few dbs where you tune it. A lot of people claim that a good, tuned ported box is not sloppy at all. I've never had any luck with ported boxed because I'm an idiot at wood work. My one attempt to build a ported box was utterly embarassing. I promptly put the sealed box back in and forgot about it.

Maybe you'll have better luck.

 

did you have the 10's in a 3cf sealed or proted box? my original thought was to just do a huge sealed box but then upon reading more i thought thatit would be too big a box and it would sound like crap, so i stuck a port in there. its not too late for me to seal the box back up if that would be a good idea though, the box is 1.9 cf per sub.

i had this system in an olds alero and hit 143.1db with this system (different box of course) and thought it would only be louder in the small cab of my ranger, i would just like to get it back there if possible....

 

When you open the cab up you are basically turning the vehicle into a 4th order bandpass box and standing right at the opening means you are standing right in the "port." If you've ever stuck your head in a port you'd notice it is a lot louder.

Ported boxes are louder than sealed boxes. On avrage 3dB, around its tuned frequincy as much as 10 (depending on design). If you are careful with your planning and design a ported box can sound fantastic. If you arent careful it can sound horrid, peaky, and "slow" or "sloppy."

Ported boxes are more efficent because instead of containing the energy comming off the back of the cone, they use a property called the helmholtz effect to amplify thoes waves within a certian frequincy range. However, with a poor design the frequincy range may become very small resulting in a peaky transient response. Also, if the port is placed too close to the sub or out of phase with the sub it can result in bad group delay. This is what causes the slow or sloppy sound of hearing the same note "twice."

 

i kind of understand the basics of ported boxes, its just that the bass in my truck sounds like there is a problem with the setup because it just does not hit hard at all unless the doors are wide open. i appreciate all the feedback guys, just let me know if there is any known fix to this problem because it seems as if no one else really knows how to fix this....

 

you have to run over rms power run closer max and you will see a difference too

 

I have that same exact thing..I always have to tell the passenger to put the window down so the bass will sound good...I hate that!! Its like i have absolutely no lows if the doors are all closed and all windows are up. would porting the box fix this or do I just have to live w/ it?

 

one other thing i have the subs firing downward-- would this make a difference and if so what is the best direction to point them?

 

the last two cars ive owned hit better with the windows down ... it was only on my accord that it didnt matter cause the subs were in the trunk

 

you cant blow that back window out i got over 4000+Rms of power and i cant do that.

 

what size is your box? how much power you sending to R and is the box you have now sealed?

 

my box is .85cf per sub and im running 400 watts and 4ohm which is rms.

 

yes but this was way back in the day with my 86 when i had like no money dude, im upgrading the system in the 86, its currently my project truck, and the back window is brand new and is not loose. That 86 is currently being lowered, and im currently in the process of shaving emblems, lights, cowl, and the tail gate. So when the trucks done im gonna redo the system with 2 15 inch type R's

 

I have a 12" solobaric L5 in a ported box and I get about 135db, its enough to make the crack in my windshield bigger if I touch where the crack is. I am using a kicker amp thats 750 watt rms and a little under 1000 max.

 

Subs down port firing sideways on the driver's side.

 

Do you have your amp turned up too high and it distorting? Sounds like when more air space is availible it equals out. I had this problem with my old 10's in a ported box with a 760w amp. Same box and amp and subs witht he same setting in the trunk of a mazda 6 sounds much better cause of the air space availible. My 2 12 P2's in a custom ported competition box with a 1200W hifonics brutus amp is crazy. Turn your amp down and see if it sounds any better.

 

Yeah, those Kicker 750.1 amps are beasts! I've seen a lot of birth sheets on those amps and they routinely put out 800+ watts rms@2ohms. I'm wishing I'd bought the 750.1 over my Alpine V12. But whatever- it's done and I'm happy!

How did you get that reading from your sub? Was it on the new TL meter? (or whatever it's called)

And I see you're from the Matagorda area. I was forever going fishing out there growing up. Mom and Dad loved drifin' the reefs with live shrimp for trout. I haven't been out there in 8 months though

 

Just my opinion here, but I have a 10" 2ohm DVC fosgate in a sealed 1 cu ft box that sounds much better when facing down, the only problem is that over time and a few bumps the cone drops out of the magnet and stops the bass, sucks. I have had to face it forward to stop this, I guess some subs are made to face down and I didnt check if this one was, I actually just pulled it out of my last truck and built a new box.

 

I love the amp, it is a perfect match for the sub.

I live in bay city but I go to matagorda beach alot to offroad and mess around with friends. I have fished out there a couple times, but I just walked out in to the water on the beach. I love it out there, so much to do compared to my crappy town.