your ohm load has nothing to do with how low your subs are going to play. they make different ohm loads for different applications. example if you wanted to run 4 subs on a 1 ohm stable amp you would need single 4s or dual 2s. the best way to make your subs play low is by tuning your box...(port length , volume, etc)

 

Adevice that dissipates one watt of power with one ampere of current flowing through it has a resistance of one ohm (R=P/I2). A ohm is a measurement of resistance and that is why when you run lower ohm loading your amp runs hotter and that is why most class a/b amps will not warenty it to run down to 1 ohm stereo or 2 ohm bridged.

 

yes i agree with the guys up top but somethings you missed.sorry to sound like a ***** im jus trying to help this guy out.the jl amp iwas refereing to was not a a/b class amplifier that is a two channel amp. now the one i was talking abot would be the jl 1000 rms class D mono amp. these amps dont get hot they consume the least amount of power out of all 3 types of car amps.and yes im very aware of ohms law and yes in fact it does play very big part in the low frequency resonance. Rms is a calculation of how much continous AC current can be handeld by the sub which then enables you to tell the lowest frequency the subs can handle continously which the jl 13 in w7 hanles all the way down to 5 hz. the reason they make different ohm loads is for people who want certain sounds from a system.now another problem area i see is the box volume...if you build to big a box it wont resonate to its fullest extent bc of to much airflow in the box tuning ports does improve sound for deeper bass but if you extend it to much you will have an annoying buzz sound on the high frequencies and whistling on low frequncies.....(sigh) i love it that im so good but i cant manage to get myself out of credit card debt

 

I dont mean to sound like a ***** but that is not true. Ohm ratings and loads play no factors into low freq. response of a subwoofer. The 13W7 will not play down to 5hz, the human ear only hears down to I think 15 to 18hz. I dont mean to come off cocky but really man you are not going to teach me anything about car audio. Now you may be able to hand it to me in car video but as far as subs, the W7's more specificly are right up my alley.



[IMG]local://upfiles/1774/17C8A9C0986F42A4B951ACB4991955FA.jpg[/IMG]

[IMG]local://upfiles/1774/BFC9E8BE3DB34CBC87013AB261806686.jpg[/IMG]

 

i'm sorry, but if you're an average person looking for a nice system, you can't go wrong with either of those choices. but i don't recommend rockford amps, they've had some problems in the past.

 

some facts on jl 1000 class D and w7 13in.RMS Power Range : 1000 WattsNumber Of Channels: 1 Low Frequency response: 5 Hz ******
High Frequency Response: 500 Hz[/ul][ul][*]Rated Power: 1000 W RMS @ 1.5 ohm-4 ohm (11V-14.5V)[*]THD at Rated Power: <0.05% @ 4 ohm[*]S/N Ratio*: >95dB below rated power[*]Frequency Response: 5 Hz-500 Hz (+0, -1dB)[*]Damping Factor: >500 @ 4 ohm/50 Hz[*]Input Range: switchable from 200mV-2V RMS to 800mV-8V RMS[*]Dimensions: 19.7"L x 9.25"W x 2.36"H[*]Differential-Balanced Input Topology: (1 pair of inputs)[*]On-board Crossover: fully-variable (40-200 Hz), selectable-slope LP (12 or 24 dB per octave)[*]Preamp Output: 2-channel (independent active filter, parallel with amp filter or full-range)[*]Bass EQ: parametric with variable boost up to 15dB and Remote Bass Control (optional)[*]Infrasonic Filter: fully-variable 24dB/octave from 15-60 Hz[*]Output Polarity Reversal: switch permits instant output polarity reversal[*]Dual mono speaker output connections: accept up to 8ga. wire[*]+12V and Ground connections: accept 4ga. wire (required)[*]now on the subSensitivity: 86.3 dBRMS Power Range : 1000 WattsPeak Power Handling: 2000 WattsImpedance: 1.5 OhmDiameter: 13 Inch[/ul][*]RMS Power Handling: 1000 watts[*]Peak Power Handling: 2000 watts[*]Dual 1.5 Ohm Impedance[*]OverRoll Surround[*]W-Cone[*]Floating-Cone Attach Method[*]Plateau-Reinforced Spider Attachment[*]Radially Cross-Drilled Pole Piece[*]Massive Forced-Air-Cooled Aluminum Alloy Frame[*]Highly Linear, DMA-Optimized Motor System[*]Huge Diameter, Progressive Roll Spider[*]Co-Extruded Double Lead Wires[*]Dual Ultra-Long Voice Coils[*]Recommended Tuning: 30 Hz[*]Sealed Enclosure Range: 1.5-2.25 cu.ft.[*]Ported Enclosure Range: 2.0-2.75 cu.ft. MAN DONT TALK **** WHEN YOU USE SUBS AS PAPERWEIGHTS!!!!!!!!!!!!!!!!!!!!!

 

ya the average person doesn't want to spend 1400 on an amp and sub (at least i know i dont). and you're right that rockord a has had problems in the past, but i have had some hands onexperience with this years line, and they are really good. haven't seen any real problems yet with the ones that I have messed with.

 

high end rockford are better than high end jls

low end jls are better than low end rockfords


in my opinion....

i would go for rockford at any price range tho

 

yeah, i've heard rockford's new line up is pretty good, i was just going on what has happened to the company in the past, but +1 for their subs.

 

Lmao at some of the morons on this topic.

FYI if you can actually hear below 25hz I will give you $100, let alone 18hz. I know I can barley hear 27hz n I prob just hear the air not the subs.