sub break in period

[Spydie]

okay....I'm gonna take that info to a local installer and see what can be done. My boxes aren't very big...maybe 14" cubed. I am struggling with my amp right now. (btw I'm very new to sound systems) As I said I upgraded from my Sony 222 to a Rockford Fosgate 301M 900W max.
I'm having a hard time finding a balance. Seems like evrytime I change cds I have to manually adjust the amp settings or it sounds like crap.
The sony was a simple plug and play amp...this one has a Punch bass switch (0db-6db-12db) Xover switch LP/AP, and a Xover frequency variable knob 50hz to 250hz. I'll have it set so whatever I'm listening to sounds awsome, then I'll either change music types or just a cd and I have to repeat the whole process of turning knobs and flicking switches. Is there a secret to finding a balance?

[BumpNGlow]

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by lakersfan1:
However, if you put it in a 1.5 cube ported box tuned to 23Hz, you'll get the full 250 watt power handling down to 20 Hz. There is a slight power handling dip to about 170 watts at 38 Hz, but the impedance is also peaked at that point at about 10 Hz, so you won't be pulling more than 170 watts out of a 250 or even a 300 watt amp at that point anyways. To get a 23 Hz tuning in a 1.5 cube box, you'll need a 3" round port of about 22" length.<hr></blockquote><p>you are going to put a 10" sub w/ a frequency response of only 31hz(which is still lower than I'd trust it) in a ported box tuned to 20?? Why would you do that? If you port it, I'd say no lower than 35,38hz. It's really just pointless below that ofr a 10.
And a 22" long port? I think that's a bit extreme... You'll probably get some nasty port noise out of that. Not to mention that the box would have to be something odd like 12x12x25 to fit that port...

[lakersfan1]

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by BumpNGlow:
<p>you are going to put a 10" sub w/ a frequency response of only 31hz(which is still lower than I'd trust it) in a ported box tuned to 20?? Why would you do that? If you port it, I'd say no lower than 35,38hz. It's really just pointless below that ofr a 10.
And a 22" long port? I think that's a bit extreme... You'll probably get some nasty port noise out of that. Not to mention that the box would have to be something odd like 12x12x25 to fit that port...<hr></blockquote><p>Look at the response of the driver and you'll understand. A 35 - 38 Hz tuning on this driver is really, really peaky. Hell, a 35 -38 Hz tuning is too high for an 8" driver for me. <p>A 23 Hz tuning on this MTX driver still has a very shallow roll-off equivilent to a sealed QTC of around .5, so he'll get plenty of low end still.<p>Anyways, the point of this exercise was to increase the power handling of the driver. Dare I say a 35 Hz tuning would make power handling matters worse, not better, especially since it sounds like he doesn't have a subsonic filter.<p>Port noise will be a non-issue. He's only got a 300 watt amp. 3" ports are perfectly acceptable for low power applications. Otherwise, Lightning wouldn't make 3" Aeroports (which happen to actually have an even smaller 2.68" inner diameter)<p>Trust me. Like I said, I just built an enclosure for the 12" version of this sub last month. I was able to run all of a 500 watt RMS amp to it with no bottoming out, even though the MTX 6000 12" also only rated to 250 watts RMS.

[Spydie]

now I really don't know what to think
good arguments either way....if I understood it.
so.....how 'bout my amp issue??? how to find a balance<p>this is what they look like anyway...<p>http://www.cardomain.com/member_pages/show_image.pl?image=member_img_a/250000-250999%2F250934_60_full.jpg<p>[ July 31, 2003: Message edited by: Darren Hyderman ]</p>

[lakersfan1]

Those boxes look pretty big for those particlar sub. I bet you can keep those boxes and just throw a port in those. If you can get the exact internal dimensions, then I should be able to model up what port dimesions would be best to modify those enclosures for more power handling and a little more ooutput.<p>Antother option is to put something in the enclosure to eat up enclosure space until you get the box small enough to handle more power. In that case, you could just pop the sub out and screw in some blocks of wood until a sufficient amount of enclosure space was used up.

[BumpNGlow]

if he knows the external dimensions and the thickness of the wood we can help him w/ the port too, but I don't know where he'd put the port b/c space looks tight on the front.

[lakersfan1]

After a closer look, if those are 10" subs, then they appear to be about 15" cubes. Assuming 3/4" wood, then you'd have about 1.4 cubes per chamber.<p>He'd need about 23" of 3" port. He'd need to put a bend in. He should be able to find some 3" PVC at a hardware store and get a 3" 90 degree bend piece.<p>Just mount it from the top. You'll probably want to assemble and glue the PVC pipe from the inside with the sub out for access to the inside.

[Spydie]

i'll get back to you with the exact measurements when I have time to pull it out. The boxes are pretty thick though. I spoke to the guy who sold them to me and made him aware that I was blowing subs often. He suggested a smaller enclosure at no charge, since I was sold the boxes and subs as a package, if it's THEIR fault I'd get proper boxes made in exchange. Good deal I guess<p>keeping in mind I'm new to sound systems, wouldn't porting the box be worse? I just figure it would be the same as if i put the sub in an even bigger box, and I'd blow it again. But if I used a smaller sealed box the internal air pressure would be increased and the sub wouldn't be able to flex so much...saving the coil. right? wrong? <p>[ August 01, 2003: Message edited by: Darren Hyderman ]</p>