Posted August 15, 200520 yr Hello all. I just ordered a 12" RLP and I am going to be running it off an MTX 2300. The sub will get approximately 700 watts rms. I am debating about what enclosure I would like to use in my car. I currently am running 2 JL Audio 12w6v2's in a sealed enclosure and it sounds good, but I am looking for a little bit different sound. I would like it to have the potential for getting loud, but with precise sounding bass. Would I be better off going with a sealed enclosure again, or should I try a ported enclosure? Also, as far as vented/ported, does slot ports or round ones matter?
August 15, 200520 yr Go ported, especially coming from a dual 12" driver setup! As to slot versus round, won't make much of a difference except that you can get away with a bit less port area using the round variety. With the 700watts, I would advocate 1.5 cu ft net volume @ 34 Hz. If you're a sucker for the low-lows and can stand to lose a bit of output over the higher frequencies, I would suggest 2.0 cu ft net volume @ 28 Hz. (The RL-p12 will displace 0.18 cu ft)
August 15, 200520 yr Author I do like the low bass, so I would probably be better suited to go with 2.0 cubed like you say. I am a newbie to the ported enclosure scene, so how do you tune a port to a certain frequency? Is it just the size of the port opening and port area in relation to the size of the enclosure?
August 15, 200520 yr Detailed overview of designing a ported enclosure: http://mobile.jlaudio.com/support_pages.php?page_id=165Helpful calculator to avoid that ungodly formula : http://www.carstereo.com/help2/Articles.cfm?id=31
August 15, 200520 yr while mike's enclosure idea's will work (i mean they are his subs..lol)..i'd build 2ft^3 tuned to 32-34hz....u'll still grab the low's, and have a higher peak in output. u won't sacrifice anything in the way of sq IME.....but any of the three will work and work well...wheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
August 16, 200520 yr Author Ok, I just went to that site to calculate the port size, and based upon frequency and xmax, the port diameter would be almost 7" and the length is like 60". I am pretty sure that isn't correct. What did I do wrong? The xmax is 24 mm, tuned to 28 hz. in a 2.0 cubic foot enclosure, right?
August 16, 200520 yr u really don't need a port that is 7" in diameter...if u go slot port, u'll need about 20in^2 minimum....however, if u go round, 4" should suffice. i'd honestly recommend doing a 4" aero, which is flared at each end..but a 4" pvc would work.go refigure, without using the port area calculator, and just use the port length one. figure using a 4" port if ur going to go round.wheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
August 16, 200520 yr Author Ok, that sounds better. It says for 4" round a 18.67" long port, or if I go 3" round, a 9.95" port. How come it is shorter for a port with less diameter? Also, does it matter where I place the port, like front of the box, back of the box, sides?
August 16, 200520 yr You might get some port whistle with a single 4" PVC port.I reccomend dual 3" PVC over a single 4
August 16, 200520 yr Author Ok, I am really confused. According to that calculator, I could use 1 3" port that is 9.95" long or 2 3" ports that are 22" long.
August 16, 200520 yr Author Ok, well the box most likely isn't even going to be 22" wide. Does it matter where the port is located on the box?
August 16, 200520 yr Not really.I had to put my ports on the side of my enclosure because i had no room for them in any other spot
August 16, 200520 yr Author With 2 3" ports I would be avoiding port whistle? Or do I need to round the edge of the port or what? Sorry for all the questions, but like I stated before I am a newbie to ported enclosures. I appreciate the advice.
August 16, 200520 yr No.If you wanted to avoid all possoble port noise i would invest in some Aero ports. They can be found on www.madisound.com.
August 16, 200520 yr the aeroports (flared) would be the best option, like i stated above. little chance for noise, even with just one 4" flared port. and it will take up little volume.teh dual 3" would be the next best, but would require a slightly larger enclosure due to add port volume. still round over the internal edges.i honestly don't think u'll get any noise, or any audible noise, with just a single 4" pvc port either. again, make sure u round off the internal edges. bb6p shows about 26m/s @ 25hz for a single 4" port in 2ft^3 @ 28hz....well below what is considered audible. and yeah bb6p isn't perfect, but it's pretty close....but for sure, the more port area, the better, usually. IMO, any of the above three options will work, it's up to u. and as to port location, it's not all that important. not unless ur chasing tenths on a meter..wheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
August 17, 200520 yr Author I think I am going to try and get my hands on a 4" round aeroport. Thanks for the advice fellas. I can't wait for the sub to get here.
August 17, 200520 yr I think I am going to try and get my hands on a 4" round aeroport. Thanks for the advice fellas. I can't wait for the sub to get here. <{POST_SNAPBACK}>I know you're gonna love it!
August 18, 200520 yr Author I never ported the w6v2's because they got way loud enough for me in a sealed box that I never felt the need to port them. That and I had no idea how to make a vented box with slot ports that would fit every nook and cranny in my trunk.
September 9, 200520 yr Author Ok, got the RLP today FINALLY! Thanks, Mike. What a nightmare! This thing is a monster! It weighs about 12 pounds more than a JL w6v2. My car is now scattered across my basement and the re-modelling of my system is under way!
September 10, 200520 yr Ah, now the fun really begins. I can't wait. Mine will be here Wednesday and I am no where near ready! Lots of box building to do.....
September 10, 200520 yr Ok, got the RLP today FINALLY! Thanks, Mike. What a nightmare! This thing is a monster! It weighs about 12 pounds more than a JL w6v2. My car is now scattered across my basement and the re-modelling of my system is under way!That you there Dave? If it is, I'm sorry about that mixup with FedEx ..they still haven't picked up the package, 26 days later I figure I'll file an insurance claim next week and either get some cash or the driver back
September 10, 200520 yr Author Yeah, that's me. I can't believe that crap. I have never had a problem with Fedex before. Now DHL, that's a different story altogether. I just can't wait to get this box built so I can finally hear that beast!
September 10, 200520 yr glad it's made it way to ya!! u'll likey..wheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
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