samslowp1s Posted April 29, 2011 Report Share Posted April 29, 2011 OK, this is far from a perfect experiment because I went by the very inaccurate ear-o-meter, but here goes. The test bed: A 1991 Honda Accord 4 door A prefab box for two 12's 2 12" 4Ohm Rockford P1's A Rockford Prime 150-1 for power (don't laugh, it what I could afford right now) In trunk, subs facing back, slot port back, shared chamber for the 2 subs. The test: After noticing how small this box actually is, I ran the outer measurements in Torres calc and found that I was tuned to approx. 50Hz. WOW thats high! LOL I am actually getting about 1.7 cubes of airspace for each woofer and, by ear of course, it sounded like it was peaking at about 45-46Hz. I ran through a bunch of tones I downloaded to test this out. I promptly removed that box to see how much Poly would help in both tricking the subs and lowering the tuning. I was quite surprised by the results. I used the standard of 1lb. per cubic foot and stapled it to the inside walls, an attempt at not having it fly out the port. LOL Once it was wired back up and in the car, I immediately noticed a difference in both quality and lowend SPL. On the ear-o-meter of course. I know I am under powering these subs by a lot but adding the poly fill killed the peaky response I was experiencing, and also lowered my boxes peak by about 5-6Hz. Now, that may not seem like much of an improvement, going from 45-46Hz to about 39-40Hz, but it makes my music sooo much more enjoyable. I do plan on building a nice box for these soon, until I can afford my DC gear but, I found this to be a good increase in sound quality and output for what I paid for the poly. Now, I know I have to state that this was in my application and may not work in all cases but, for those of you who are in my situation it can't hurt to at least try it out. It is really inexpensive to try and it may get to where your current equipment is at least bearable for you. That is, until you get your monster set up. So anyone with questions about my VERY little experiment, please feel free to ask. I will probably post a small build log and if I can TL numbers, with and without poly. On that note, anyone in San Diego, or know someone in San Diego with a TL. I would very much enjoy getting this baby system metered to see just how inaccurate my ear guess is. Thanks for reading Link to comment Share on other sites More sharing options...
fecupe2001 Posted April 29, 2011 Report Share Posted April 29, 2011 I will probably post a small build log and if I can TL numbers, with and without poly. On that note, anyone in San Diego, or know someone in San Diego with a TL. I would very much enjoy getting this baby system metered to see just how inaccurate my ear guess is. This would be AWESOME man, that same test was asked to me on my "SPL gains" topic but i don´t find poly cheap over here to make the test, would be great if you do that!! I´m the SPL Gains topic creator!! wanna get louder?? check this: SPL Gains. Panamenian 2009 & 2010 & 2014 Bass Race 149.9 Champion! 2 15" subs and a 2K wired at 1 ohm, http://www.stevemeadedesigns.com/board/topic/167788-fecupe2001-2-15s-on-a-2k-video-on-page-3/ 8 Massive 15" subs and small power, http://www.stevemeadedesigns.com/board/topic/179296-fecupe2001s-8-15s-4th-order-bandpass-wall/ Link to comment Share on other sites More sharing options...
00hoe88 Posted April 29, 2011 Report Share Posted April 29, 2011 i got a ported box in a trade once that a shop made that had polyfill in it and they put mesh up over the back of the port to keep it in but it would flap and make all kinds of horrible noise so that and the poly fill came out and it sounded alot better and somewhat louder head unit - pioneer DEH-P5100UB subwoofer - nothing speakers - powerbass components amp - nothing Link to comment Share on other sites More sharing options...
TeamHT Posted April 29, 2011 Report Share Posted April 29, 2011 I honestly think you heard what you wanted to hear. Tell me...does this smell like chloroform to you? Link to comment Share on other sites More sharing options...
White Lightning Posted April 29, 2011 Report Share Posted April 29, 2011 but i don´t find poly cheap over here to make the test There is a walmart in Callaway ... Walmart always has polyfill ... cheap ... Kenwood / HELIX / Linear Power (For The Love Of Music) / Brutal Sounds / OverKill Electric Co Questions About Sound Quality ?? Try Here ... Sound Quality, What does it REALLY mean ?? SMD SOTM Winner "White Lightning" 1997 GMT400 Chevy Silverado "The Green Dickle" 1994 GMT400 Chevy "Phantom Dually" Randal's 2007 Chevy Avalanche (we haven't named this one yet) Dylan's "Brutal" 17 Chevy Cruze RS Hatch Link to comment Share on other sites More sharing options...
mr.p Posted April 29, 2011 Report Share Posted April 29, 2011 I can attest in my bandpass that a bunch of polyfill helped lower my response...On low power...We will see on the 12k back to back testing DCAUDIO BALLS DEEP Link to comment Share on other sites More sharing options...
fecupe2001 Posted April 29, 2011 Report Share Posted April 29, 2011 I honestly think you heard what you wanted to hear. haha placebo?? but i don´t find poly cheap over here to make the test There is a walmart in Callaway ... Walmart always has polyfill ... cheap ... I don´t live in the US hommie... I´m the SPL Gains topic creator!! wanna get louder?? check this: SPL Gains. Panamenian 2009 & 2010 & 2014 Bass Race 149.9 Champion! 2 15" subs and a 2K wired at 1 ohm, http://www.stevemeadedesigns.com/board/topic/167788-fecupe2001-2-15s-on-a-2k-video-on-page-3/ 8 Massive 15" subs and small power, http://www.stevemeadedesigns.com/board/topic/179296-fecupe2001s-8-15s-4th-order-bandpass-wall/ Link to comment Share on other sites More sharing options...
White Lightning Posted April 29, 2011 Report Share Posted April 29, 2011 I honestly think you heard what you wanted to hear. haha placebo?? but i don´t find poly cheap over here to make the test There is a walmart in Callaway ... Walmart always has polyfill ... cheap ... I don´t live in the US hommie... oh shit ... sorry ... I read panama city, I misread the other ... There is not a pillow you can open up ??? same material inside ... Kenwood / HELIX / Linear Power (For The Love Of Music) / Brutal Sounds / OverKill Electric Co Questions About Sound Quality ?? Try Here ... Sound Quality, What does it REALLY mean ?? SMD SOTM Winner "White Lightning" 1997 GMT400 Chevy Silverado "The Green Dickle" 1994 GMT400 Chevy "Phantom Dually" Randal's 2007 Chevy Avalanche (we haven't named this one yet) Dylan's "Brutal" 17 Chevy Cruze RS Hatch Link to comment Share on other sites More sharing options...
samslowp1s Posted April 29, 2011 Author Report Share Posted April 29, 2011 i got a ported box in a trade once that a shop made that had polyfill in it and they put mesh up over the back of the port to keep it in but it would flap and make all kinds of horrible noise so that and the poly fill came out and it sounded alot better and somewhat louder Like I stated, this is very application specific. I have heard good and bad stories of the use of poly fill in enclosures. That is why I did the little ear test, just to see if it would make a difference to the sound. I have been putting systems together for over 13 years and only used it twice. Once in a sealed box and now in this small ported box. The only thing I see different, in most set ups that have a bad reaction to using it, is the power they are using for the subs. Oddly enough, both times I used poly fill, I had too little power to really maximize the subs output. The first time I was under powering the sub by at least 100RMS and this time, I am closer to 110-120RMS under for the pair. I do see how some people can actually gain a nice bump in SPL by tricking their subs with this though. If done correctly, it is pretty hard to guess how much you need to put in, you can effectively lower your tuning and increase output from your subs. Link to comment Share on other sites More sharing options...
DylanH Posted April 29, 2011 Report Share Posted April 29, 2011 I kind of want to try this now but I'm afraid it might sound like ass and I won't be able to get rid of it lol http://www.youtube.c...er/SmallTownSPL 2002 Chevy Blazer Substage: Shhh, its a secret Mids and Highs: Stock-Going to change soon Amp:MTX 92001 Wire:1/0 Welding cable Electrical:Stock http://www.stevemead...__fromsearch__1 I hope she was meaning that to you. Any who.... You dont say you wanna have dinner in the first damn post. talk to her first. I say find out if the status was torwards you.. Here try this... "Hey hows it going ( notice smiley face makes everything better ) I saw your status. "You are far from usual".... So is my dick... Wanna Fuck tommorow???" Or send her message saying "hey" she replies back "hey" when this happens reply Wanna fuck (INSERT ADDRESS HERE) Quote of the SPL Creed ; back in the day my girlfriend gave me a choice between her and my love for car audio, I told that bitch I've made harder decisions at the Coke machine. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.