blake_mooney Posted August 8, 2003 Share Posted August 8, 2003 but im really scared to i have it.... im just afraid of screwing something up.... can someone walk me through adding polyfill to my pro media 5.1 duel 8" sub .... thanks in advance any help would be greatly appreciated .... Quote Link to comment Share on other sites More sharing options...
prodj101 Posted August 8, 2003 Share Posted August 8, 2003 dunno, I can't help you with that. but I recently added sound dampening material to my JBL sub, just be sure you don't block the port. also, keep in mind the pm's run very hot, adding insulation may increase the heat levels to dangerous levels. Quote Link to comment Share on other sites More sharing options...
blake_mooney Posted August 9, 2003 Author Share Posted August 9, 2003 ---------------- On 8/8/2003 4:10:07 PM prodj101 wrote: dunno, I can't help you with that. but I recently added sound dampening material to my JBL sub, just be sure you don't block the port. also, keep in mind the pm's run very hot, adding insulation may increase the heat levels to dangerous levels. ---------------- whats the port? Quote Link to comment Share on other sites More sharing options...
JasN00b Posted August 9, 2003 Share Posted August 9, 2003 ---------------- On 8/9/2003 9:16:40 PM blake_mooney wrote: ---------------- On 8/8/2003 4:10:07 PM prodj101 wrote: dunno, I can't help you with that. but I recently added sound dampening material to my JBL sub, just be sure you don't block the port. also, keep in mind the pm's run very hot, adding insulation may increase the heat levels to dangerous levels. ---------------- whats the port? ---------------- the tube that leads to the hole in the front of the sub Quote Link to comment Share on other sites More sharing options...
dougdrake Posted August 9, 2003 Share Posted August 9, 2003 Why do you want to polyfill? Quote Link to comment Share on other sites More sharing options...
blake_mooney Posted August 10, 2003 Author Share Posted August 10, 2003 ---------------- On 8/9/2003 10:15:01 PM dougdrake wrote: Why do you want to polyfill? ---------------- for better bass extension.... Quote Link to comment Share on other sites More sharing options...
michael hurd Posted August 10, 2003 Share Posted August 10, 2003 Polyfill wil not add bass extension! If you do manage to stuff polyfill in through the port, you will change the characteristics of the sub response. In a resistively ported enclosure ( similar to aperiodic ) the enclosure will behave more like a sealed enclosure, raising the fb and adding more midbass. Buy an other subwoofer and add it to the one you have. Quote Link to comment Share on other sites More sharing options...
tpg Posted August 10, 2003 Share Posted August 10, 2003 If you buy another sub, odds are you will be using only that one, as the PM sub does not exactly have the same "home theatre bass" sound. I don't know how to say it exactly... Build a sonosub or something, and turn the PM sub down. Quote Link to comment Share on other sites More sharing options...
pinipig523 Posted August 10, 2003 Share Posted August 10, 2003 buy another sub - exactly what you need. if u are not satisfied with the bass yo uare getting right now - YOU WILL NOT BE SATISFIED even after the polyfill or whatever mods you do. seems to me like you need a bigger sub (ht caliber). get one and you will see (i mean hear) what you have been missing all along. Quote Link to comment Share on other sites More sharing options...
BBB Posted August 10, 2003 Share Posted August 10, 2003 Look out! Back it up! Beep! Beep! Beep! Beep! Quote Link to comment Share on other sites More sharing options...
blake_mooney Posted August 10, 2003 Author Share Posted August 10, 2003 ---------------- On 8/10/2003 4:29:56 PM pinipig523 wrote: buy another sub - exactly what you need. if u are not satisfied with the bass yo uare getting right now - YOU WILL NOT BE SATISFIED even after the polyfill or whatever mods you do. seems to me like you need a bigger sub (ht caliber). get one and you will see (i mean hear) what you have been missing all along. ---------------- i disagree i think the Pro Media 5.1 sub sounds better then a LOT of home theater subs ive heard.... Quote Link to comment Share on other sites More sharing options...
blake_mooney Posted August 10, 2003 Author Share Posted August 10, 2003 ---------------- On 8/10/2003 12:44:51 PM trespasser_guy wrote: If you buy another sub, odds are you will be using only that one, as the PM sub does not exactly have the same "home theatre bass" sound. I don't know how to say it exactly... Build a sonosub or something, and turn the PM sub down. ---------------- i disagree its not that im not satisfied with the bass its way more then enough im just curious if i can make the sub sound better by modding it.... Quote Link to comment Share on other sites More sharing options...
pinipig523 Posted August 11, 2003 Share Posted August 11, 2003 u havent heard real HT subs then. Quote Link to comment Share on other sites More sharing options...
pinipig523 Posted August 11, 2003 Share Posted August 11, 2003 bottomline: u can polyfill your sub - but u run the risk of overheating your internal components - especially since the amp powers the speaks as well - and the 5.1s DO have a history of failing amps (i have even seen blown capacitors - which means that if that cap blew in YOUR polyfilled sub... well you could start a FIRE). by polyfilling - u DO NOT get extra bass extension... u DO GET extra spl - probably between 1-3db. but is it worth it to polyfill a 5.1 sub - knowing the effects it might have on the rest of your system (functionality/longevity wise)? IMHO, nope. i now know that u do ARE SATISFIED with your sub - it just seemed like u werent based on your topic's title with like half a dozen ?-marks on your earlier (but related) posts. maybe if u had less ?-marks, TPG and I wouldve thought u were satisfied with your pm sub. and once again - the pm sub is NOWHERE near bonafide HT subs. Quote Link to comment Share on other sites More sharing options...
prodj101 Posted August 11, 2003 Share Posted August 11, 2003 what he means when he says the pm 5.1 doesn't quite sound the same as ht subs is that it doesn't extend as low. computer subs tend to be more punchy in the 50-60 hz range, they can not contend with a real ht sub. I once had my PM 2.1 sub set up in my ht system temporarily before my RSW-15 came, let me tell you, I COULD tell a difference, and a huge one. also, I recently took apart one of my 2.1 sat's, it had acoustic stuffing inside, I don't think the sub's would be any different. Quote Link to comment Share on other sites More sharing options...
formica Posted August 11, 2003 Share Posted August 11, 2003 ---------------- On 8/11/2003 1:39:29 AM pinipig523 wrote: by polyfilling - u DO NOT get extra bass extension... u DO GET extra spl - probably between 1-3db. ---------------- Ummm... i'd have to disagree. I don't have the T/S parameters for the driver, but he correct in assuming that he will get a slight increase in the subwoofers bass extension. Adding polyfill (or other loose fibre fill) will make the enclosure act like a slightly larger enclosure (between 5 to 30% depending on the amount of fill and the T/S parameters of the driver). Plugging a larger enclosure into speaker formulae will give slightly increased bass extension, and DECREASED overall SPL. It'll act a little like a EBS (extended bass subwoofer). Two things to note: 1) Without decreasing the length of the port, it's tuning will now create a small plateau in the response, 2) EBS woofers are more likely to bottom-out (pass their maximum extension) with less power. That said, the apparent acoustic volume difference should be small enough that the undesirable tuning plateau and max-extension will all be as negligible as the increased bass extension. Subwoofers (as well as speakers) are built from compromises, and tweaking simply personalizes them. Later... Rob Quote Link to comment Share on other sites More sharing options...
fabulousfrankie Posted August 11, 2003 Share Posted August 11, 2003 ---------------- On 8/10/2003 11:20:40 AM michael hurd wrote: Polyfill wil not add bass extension! If you do manage to stuff polyfill in through the port, you will change the characteristics of the sub response. In a resistively ported enclosure ( similar to aperiodic ) the enclosure will behave more like a sealed enclosure, raising the fb and adding more midbass. Buy an other subwoofer and add it to the one you have. ---------------- I disagree with this, but I do agree that you run the risk of overheating the amplifier components. In the end, you wouldn't be satisfied if you're amp died(I didn't know of a history of problems, though). Having said that, I did put fiberglass insulation(does the same thing as polyfill) in my PM2.1 sub, with no ill effects. In my case I felt I could get away with it because I'm right next to the sub and my listening with them is all at very low levels. Quote Link to comment Share on other sites More sharing options...
fabulousfrankie Posted August 11, 2003 Share Posted August 11, 2003 I forgot to add why I disagree. By adding polyfill, the apparent box volume teh woofer sees increases, but the port obviously doesn't change size. When you increase the box size, you're port size needs shorten to keep the same tuning frequency. Since you are increasing the apparent box size and keeping not shortening the port, the suboofer is now tuned lower than it was. With the lower tune you increase the extension a bit. Quote Link to comment Share on other sites More sharing options...
fabulousfrankie Posted August 11, 2003 Share Posted August 11, 2003 Looks like we posted the same thing Rob. I guess while you were posting I was writing my reply. Quote Link to comment Share on other sites More sharing options...
pinipig523 Posted August 11, 2003 Share Posted August 11, 2003 interesting - polyfilling may add some extension. i always thought it only added spl - i love this forum. i learn new things everyday! polyfilling my infinity sub may be a coming reality after all. however, i still dont think that polyfilling a 5.1 sub is a smart thing to do. the downside of overheating the amp is too much for only a slight increase and slight extension. Quote Link to comment Share on other sites More sharing options...
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