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View Full Version : lowering the tuning of a ported enclosure



mat3833
04-07-2013, 05:38 PM
so i had a box built by double07 and it sounds fantastic. after listening to it for awhile i came to the conclusion that i should have had it tuned a bit lower for my taste. currently it is tuned to ~32hz and it houses 2 SPLaudio 8's. the problem is the final note in "I Put On" does not play hardly at all. the subs move and there is airflow, but hardly any output. im only putting ~600W to the pair so that is probobly part of the issue. what i want to do is try and effectivly lower the tuning to ~29hz using polyfill in the actual "enclosure" and lining the port with the Quilt-style polyfill.

i have used the quilt-style pollyfill in Tapped horns ans T-lines before with nice results, but since this is a tradtional ported enclosure im not sure how it will react. when i did the T-Line for a friend we saw an effctive tuning drop of ~3hz, which would be exactly what im looking for. the only problem is i cant line the whole port, just the short part of the "L".

does anyone have experiance using Polyfill in a ported enclosure on here?

Matt

BrownVanMan
04-07-2013, 07:20 PM
Everything I've read said pollyfill in a ported box makes things way worse

fasfocus00
04-07-2013, 07:29 PM
batt version of polyfill and you'll be fine, just make sure to spray a little adhesive or small staples so the batt doesn't blow all over the enclosure.

hispls
04-07-2013, 07:37 PM
It should lower tuning a bit, I've done it in the past and noticed a slight difference. Keep in mind it's not going to be dramatic, and you should really consider more cone area if you want to really notice <30hz

mat3833
04-07-2013, 08:52 PM
well new subs/enclosure is out of the picture right now. so i picked up some "quilt" batting and went to put it in, but i couldnt find the stapler. so i said **** it and wired the subs to 1 ohm while i was in there and set the ZX-750 to 1000W. much better now. once i locate the stapeler i will polly some of the enclosure and see if i like it.

Matt

mlstrass
04-08-2013, 06:10 AM
personally I would have done a port reducer to drop tuning or stop playing ****** music like "put on"...

mat3833
04-08-2013, 01:53 PM
lol, making the port a smaller size would introduce port noise. and i dont listen to that song often, it just happened to come on and i noticed i couldn't hear or feel the final note on the bass line.

thanks for doing 2 useless things in one post. A. being a ******* **** B. not even remotely providing constructive input regarding the question.

Matt

mlstrass
04-09-2013, 04:36 AM
lol, making the port a smaller size would introduce port noise. and i dont listen to that song often, it just happened to come on and i noticed i couldn't hear or feel the final note on the bass line.

thanks for doing 2 useless things in one post. A. being a ******* **** B. not even remotely providing constructive input regarding the question.

Matt

You're right cuz I've only built a shitton of ported boxes with port reducers. Have you tried a port reducer and heard port noise?

Thanks for being a clueless kid and asking a question and not listening to the answer :crazy:

mlstrass
04-09-2013, 04:44 AM
Also your SSF and lack of cone area is more then likely why you don't hear the low note, but again ignore that cuz I'm an idiot

JL4LIFE

mat3833
04-09-2013, 05:29 PM
the subsonic on the ZX-750 is hard-set at 25HZ so nothing i can do there, and yes i actually have played with port reducers. considering you have no clue how old i am, or how many enclosures i have built/designed you are now just throwing ignorant insults. let me break it down for you. i will try to use small words so you can understand everything. if you have trouble just click this link ( Dictionary.com - Free Online English Dictionary (http://dictionary.reference.com/) ) and just type the word you dont understand in the box at the top of the page.

port reducers are great if you already have a large port and can afford the reduction in port area without hitting the vent/mach threshold for the port size/frequency you are aiming for. but considering i am trying to play 29hz, a larger port would be better. there is already some slight port noise when playing 32hz tones. only audible when you have the trunk open, but there is noise. your idea is sound, however taking into account the application, it is not the right choice.

and your cone area comment is partially correct. i could play 29hz solid with a single 10 in a 32hz tuned enclosure, granted it was on a good bit of power and the driver itself was built to be a low-end monster. the problems that i have currently are lack of power, the lack of an adjustable subsonic filter, and the tuning of the enclosure. when i had the enclosure built i decided on 32hz after wanting to go with 28hz. in hindsight i should have gone with 28hz and been done with it. since i cant add power right now and i cant change the subsonic, that leaves me with changing the tuning of the enclosure. and since i have had good luck with polyfill in the past in my home theater enclosures i figured i would post a question on here hopeing to get car-related insight since cars and livingrooms are two completley diferent animals.

obviously i should have gone to DIYMA or one of the other forums i frequent instead of to CA.com. aparently asking a logical question and expecting a thought-provoking response is too much to ask over here. and for the record, 2lbs of polyfill batting in the chamber and 1lb of polyfill batting lining the walls of the port acomplished what i wanted, it also got rid of the minor port noise.
mlstrass ; thanks for your "input" and have a nice day. good luck with your enclosure building and if you ever want to learn about home theater hit me up, then we will see who is the "clueless kid who is asking questions and not listening to the answers" :-)

Matt

mlstrass
04-10-2013, 03:31 AM
My HT plays down to 12Hz just fine, you mirin brah?

mlstrass
04-10-2013, 03:33 AM
next time build the right enclosure and you won't have to use band aid fixes :p: