Another Amp/sub combo question?

Question

Hi i have a Crunch Audio P1100.2 Amp 1100W 2 channel...

1100W x 1 is Bridged at 4Ohm
550W x 2 is at 2Ohm
275W x 2 is at 4Ohm

besides me being confused as to how it makes 1100W by bridging 275W at the same Ohm rating

I'm curious if these subs will work with them I read somewhere that your supposed to run an Amp with a RMS 80-90% of what your subs RMS is as a general rule of thumb ive also heard other things.

So these subs I'm looking at are a cheap brand but these subs are highly rated on amazon and other websites... but because of how cheap they are...(about 45$ a piece for a 12" sub on sale OR only 38$ for the 10" model)... I assume/suspect they are over rated as far as power goes...

(12") They claim 500W RMS/1000W Peak which makes me think closer to 300W RMS/600W Peak
(10") They claim 400W RMS/800W Peak I think closer to 250W RMS/500W Peak

I plan on running 2 subs @ 4OHM since the subs are 4OHM

Of course I may be totally off the radar thats why I'm asking....

Answer 1

Your not brdg. 275, your brdg. 550 to get your 1100watts, as for the OHM, it's because your using 2 2ohm channels together (brdg. ) which comes out as your 4 OHM. Now that is not always the case, but to understand it read OHM's law. found here http://www.caraudiohelp.com/ohms_law/ohms_law.htm.

As for the power of the low priced subs, you'd do well to think them over rated, and you thinking on the power to run to them 80-90% is a good idea.( but more often then not, you can do more damage to your subs by running to little power to them, as apposed to running to much)

If you want to run 2 4 ohm subs go here, http://www.rockfordfosgate.com/rftech/woofer_wizard.asp and it will show you how to hook them up the right way to get the right OHM.

Answer 2

With a $38 10" sub or a $45 12" sub, you'll be really lucky if it can actually handle 150 watts RMS. The specifications listed for cheap subs by noname importers simply can't be believed.



When comparing and selecting an amplifier and subwoofer(s), there are 2 parameters that need to be matched. These are 1) Impedance; and 2) RMS continuous power. To properly match the impedance you need to know the individual voice coil impedances, the number of voice coils, and the final number of subs that will be installed. You want the final connection to present the lowest impedance into which the amp can be safely operated. Operating into a lower impedance than the amp is rated to handle will often result in the amp going into "protection" mode and even worse, damaging the amp internally. Operation into a higher impedance is OK, but the power will be reduced. For example, an amp will deliver twice the power into a 2 ohm load than it will into a 4 ohm load.



There are different ways to rate a subwoofer's power handling capabilities. But, the ONLY meaningful measurement to consider is continuous RMS watts. 2,000 watts "peak" is an absolutely worthless rating. The subwoofer may actually be able to handle 2,000 watts for 5 or 10 milliseconds. Connecting it to an amplifier that outputs 250 continuous watts RMS and playing it for an hour may very likely burn up the voice coil(s) and cause permanent damage. But a subwoofer rated to handle 250 continuous watts RMS can be safely connected to the same amp and played all day, month after month, with no damage or degradation in sound quality.



Yet manufacturers frequently market substandard products with high 'peak' ratings. Most are cheap flea-market brands that produce more noise and distortion than good accurate bass. It's better to pay a little more for a subwoofer that will last longer and sound better.



If the subs are single voice coil and 4 ohms, you can only wire them to present a final impedance of 2 ohms (parallel) or 8 ohms (series). The pair cannot present a final load of 4 ohms.



For a few bucks more, you can purchase good quality, good sounding, entry level subs. For example, these Alpine Type E's will be playing long after your $39 sub has burned up. And even better, they will sound pretty good.



http://www.crutchfield.com/p_500SWE1043/Alpine-SWE-1043.html?tp=111



The 12" versions are only $11 more.



http://www.crutchfield.com/p_500SWE1243/Alpine-SWE-1243.html?tp=111



Another choice for a decent entry level sub would be Rockford-Fosgate. This 10" is only $50.



http://www.sonicelectronix.com/item_17889_Rockford+Fosgate+PRIME+R1S410.html



The 12" version is another $10:



http://www.sonicelectronix.com/item_17890_Rockford+Fosgate+PRIME+R1S412.html

Answer 3

GET MONOBLOCK AMP MULTI CHANNEL AMPS ARENT FOR SUBS HERES A LINK

http://www.sonicelectronix.com/viewcat.php?category_id=23&f_163_min=2501&f_163_max=0