Sloppy subs.

[Pernilongo]

I have been reading, but we all know it takes time. Everything I have learned has been telling me to go sealed. The Rockfrod website lists the Qts as .55, And Ive read anywhere about .5 is sealed territory, Is that right?

Ive also read that polyfill will make the box seem larger than it is, as the air has a longer distance around all the polyfill then in open air. Something like a 10% increase in volume, Just barely noticable.

What is your reccomendations do you have for good drivers? Ive heard the RE XXX are only SPL spakers, are any of the others good?

p.s. I wasnt asking for a system design down to the cut sheet, just a step in the right direction, but I think I've found it.

Thank you guys for your time, and realize how long it took us to learn the Supra, Now I just have to Teach myself this stereo stuff. Ive only had the past few days to start on this stuff, and Im sure you guys know how much there is to learn, And worse yet, how hard it is to learn the right stuff off of the internet.

Again thank you guys for your time and knowledge::salute::

Well. you know ported boxes do sound very good. I myself prefer them over sealed. But, there always a big but, the driver and the box need to match. RE is a very good choice, very good drivers. CDT and there are plenty of others but not so many that combline SPL and SQ. Also, might try Image Dynamics, they have very very good subs. The best part that on their website they have a forum section where you can get an advise from the owner of the company him self and his staff that is very professional at box and system designs. If you don't really want to do all the reading and experimentation ask them what they recommend, they are very good at advise and patient too. The best part they can even give you a blueprint for the box- ported or sealed. At least you can work with someone there, you know, not just collect opinions. it gets complicated with your project.

P.S. Polyfil makes air heavier thus makes the sub "think" there is more of it.

 

[Anth505]

So far, the best subs I have ever owned have been JL Audio. I'm very sound quality oriented and don't care much for SPL, although the JL's I have owned in the past could hit really hard. For sound quality, I loved them. Thier entry level subs are very affordable and sound amazing. Their top end stuff is simply awesome.

I have also owned MTX which were pretty good, Orion, also good but more for SPL, and Alphasonik (sp?) which were very good. I currently have a no name sub in my daily driver which (mainly thanks to the amps and box) sounds decent. I will be installing a new system in the fall and will be using JL's for sure.

I don't want to sound like a commercial, there are MANY excellent subs out there but like I said earlier, your results will be mostly influenced by the installation not the product (assuming you are using decent stuff).

 

[toyo4life]

I've stated on other post that I've been a pro installer nearly 20 years so i've seen alot of systems and heard a lot of problems. What most of these guys are saying is right, but you said the box sounded fine in your buddy's system, right? well that makes me want to take a look at your system. What are using to get your sub signal? Is it a dedicated sub out from a head unit? If so you may need to have a subsonic filter. It will cut out any signal below15-20hz. ported enclosures lose control of cone motion below their port tuning freq. this will cause the symtoms you described. Now lets say you don't have dedicated sub outs and you are using a line level converter. is it shared with another pair of speakers? Example did you take speaker level off your rear spaekers while leaving those speakers hooked up? This can cause a problem called microphonics, the subs cause the rear speakers to move, creating voltage which is the fed back into the amp as signal not in the orginal signal. the louder you pla the worse it gets.
I think most likely the first problem it what you are seeing. Some radios have a subsonic filter built in some don't.
hope this helps.

 

[teedoff00]

+1 on the JL Audio subs, best bang (both SPL and SQ) buck in my opinion.

 

[FullNelson]

I've stated on other post that I've been a pro installer nearly 20 years so i've seen alot of systems and heard a lot of problems. What most of these guys are saying is right, but you said the box sounded fine in your buddy's system, right? well that makes me want to take a look at your system. What are using to get your sub signal? Is it a dedicated sub out from a head unit? If so you may need to have a subsonic filter. It will cut out any signal below15-20hz. ported enclosures lose control of cone motion below their port tuning freq. this will cause the symtoms you described. Now lets say you don't have dedicated sub outs and you are using a line level converter. is it shared with another pair of speakers? Example did you take speaker level off your rear spaekers while leaving those speakers hooked up? This can cause a problem called microphonics, the subs cause the rear speakers to move, creating voltage which is the fed back into the amp as signal not in the orginal signal. the louder you pla the worse it gets.
I think most likely the first problem it what you are seeing. Some radios have a subsonic filter built in some don't.
hope this helps.

When the amp was conected to his speakers, the subs had the same sloppy sound to them mine did, when he connected his amp back up, they sounded fine.

The amp is connected through dedicated RCAs from an Alpine ida-x100

Maybe one of these would help?
subsonic filter

 

[toyo4life]

When the amp was conected to his speakers, the subs had the same sloppy sound to them mine did, when he connected his amp back up, they sounded fine.

The amp is connected through dedicated RCAs from an Alpine ida-x100

Maybe one of these would help?
subsonic filter

Yeah harrison is quality stuff. Plus it works passively at rca levels.

 

[pbasil1]

Just did a quick scim over the last few posts.

.5 cu/ft is a bit small for 12"s. Even the p2's. I would put them in a box with roughly .9 cu/ft net volume per sub. (.9 cu/ft after deducting the volume of the speaker its self, and any internal baffling.) Then stuff it with polyfill. And be sure the box is sealed well. Use plenty of glue and caulking when building it. And if you feel up to the task, internal baffling will make for a cleaner and more responsive sub.