Memphis PR1000 too much for 2 12" Type R's in a big box?

[Bobyota 10+ year member]

I was looking at buying a 1000w (at 1 ohm) Memphis Power Reference amp and using two 12" Type R's in a sealed box that's about 4 ft^3.

Now I believe the R's are rated @ 300w rms.....but people say they can take more. Alpine recomends .7-1.0 ft^3 of space for each sub.....so it looks like my box would be about twice as big as they recomend. So that makes the situation worse right? Cause I hear people say the bigger the bo is, the less poewr you have to use.

So am I going extreme overkill here for these subs? Maybe 15" R's could handle this power and box better? Good thing there is the box I got was made for 15's and a piece of MDF was screwed over it to use 12's.....so I could use it for 15's again.

And the last thing....I want good SQ. My friend just swapped from 15's to 12's (Memphis PR's in the same box I'm talking about) and the SQ was better with the 12's. So do y'all think the 12" r's would offer much better sq than the 15's?

Thanks for helping me out again //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif Maybe I'll finally get around to buying something soon //content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

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[Bobyota 10+ year member]

Ok that makes sense Jmac. Do you think the 4 ft^3 sealed box would be enough to make 15" r's sound good with that amp? I think alpine recomends 1.5-2.3 ft ^3 per sub.

 

[Bavarian3 10+ year member]

im sure the R's can handle it. The 15's for sure will handle it because theyr 500 rms. if ur gona get 12's just keep the gains down and ull be fine.

 

[Bobyota 10+ year member]

Should be alright. I'm not exactly familiar with good box sizes for 15s as I have little experience with them (Everyone always gets 12s and rarely do I see 10s and, even rarer, 15s). Usually Alpine recommends an enclosure that's on the small side for additional power handling capabilities, so I would think you'd be looking at a 0.85ish Qtc ... The computer I'm on won't read PDF files, so I can't check Qtc, but go to this site ...
http://www.diysubwoofers.org/sld/sealed1.htm

And enter the required T/S Parameters and see what you get ...

Lower Qtc = better SQ

Jmac, if I calculated correctly, I'd have .8 Qtc with ~4 ft^3 box. I believe that web page said .7 was a good #, but it must have been talking about home stereo because it said that a car sub box could use a larger #.

Are there any other #'s beside Qtc that correspond with SQ?

Is there anywhere I can gt definitions for some of these abreviations like Qtc, Vas, Fb, etc?

Thanks a lot for giving me that link Jmac.....I love to punch in #'s on a calculator.....must be my accountant mom's genes //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Got any more box building sites with good info I may wanna look at? Thanks a lot, you've been a big help //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Bobyota 10+ year member]

Thanks again Jmac. Maybe that almost .8 of QTC for the setup I wanted to run wouldn't be that great for me (wanting really good sq). The dual 2 ohm 15's wouldn't put the amp at 1 ohm to get the poer out of it. Thinking of building my own box with some 12 R's and about 600w. I'll punch some #'s in and see how that setup looks....