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I just received two Rockford Fosgate P3SD212 subs today, and upon opening the box it reads that i need to break in my subs.
What is the proper breaking in method?
The subs are rated 400w RMS, 800 peak. I have a 1800w Kenwood KAC9013D wired at 2 ohms, pushing 900w. This puts 450w per speaker, running them 50w past their RMS limit, What should the gain settings and such on my amp be? I've blew previous subs in my vehicle, and would like for these to last.
It has a 18db bass boost, a input sensitivity control, a ISF switch with 15 and 25 Hz settings, and a LPF switch with settings from 50 to 200 Hz.
Thanks for all the help.
The subs will take a while for the suspensions to loosen and for them to start playing well as they "break-in".
It used to be recommended to not run them up to full power during this period. Generally accepted that this is not required anymore (was never required?).
Take it easy on them for a couple of weeks if you want, or don't .....
450W should be fine - you want the gain just below when the subs start distorting. Clipping from too much gain blows speakers faster than overpowering them.
Bass Boost - generally off - use carefully if you like what it does to the sound.
Input Sensitivity - That is the gain control.
ISF - subsonic filter - set that to the lowest rated setting of the box or subs - 20 is likely good if you don't know.
LPF - probably start around 100 and adjust for best sound.
2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock
speakers, no amp, no subs
How can you tell if the sub is distorting?
My situation is with a 10" Alpine Type-R, and a Kenwood KAC-7201(specs listed below). I'm not sure if I should use this combination for sub and amp, but it's all I have for a couple weeks.
Any advice? =D
It sounds almost as if it is cutting in and out, like when you turn up your stereo on factory speakers very loud with the bass all the way up.
Thats what distortion sounds like, some times it can sound like a static.
i guess it takes more getting used to to listen for distortion in a subwoofer than regular speakers, but its the same concept. it gets grindy, rather than a good smooth bass sound. thats my best effort of a description.
but im still not sure what people refer to as "clipping"
Infinity reference 1242 subwoofer, kicker zx250.2, stock speakers in doors/rear deck, Kenwood KFC-T207 Component Tweeters
Fenix Ignitionbut im still not sure what people refer to as "clipping"
Basically, it's the same thing.
Clipping occurs when the gain is set too high.
Basically, what it is referring to is what you would see viewing a Sine wave on an Oscilloscope. BCAE1 talks about it here and in this image:
See how the normal peaks (the orange curve) get "clipped" (the aqua curve), when the overall gain is increased to the level of the pink curve?
What this does is increase the area under the curve, which increase the power going to the sub, which is what ultimately melts them. If it hasn't been linked in this thread already, see this also.
I think I have a much better idea of what to look for now. Thank you, fellas =)
One question though,- I read in one of the threads that 'Underpowering' is just bs and It's not unhealthy at all to use a lower-powered amp for a stronger sub. Is this true? I remember hearing stories of people blowing their subs with low-powered amps, with the gain at the lowest setting.. I'm not sure though... Anyone?
2 things ive heard.
1, with home stereos, with a 4 ohm speaker and 8 ohm reciever, i was told that the speaker will "pull" too much (power?) from the reciever, causing damage to it.
and the other thing
subwoofers RMS is basically the maximum reccomended nominal (correct use of the word?) power, and you know about peak power. so a sub should handle fine with less power. at least it shouldnt blow the sub. but i heard someone mention that a sub can overload an amp that doesnt output enough power? i dont think it was a real credible source, so i still dont know for sure.
what i do know, is that my friend has a kicker zx250.2, and one infinity 1242 like my own, and he maxed the gain and bass, and had it wired to the left channel only (85 watts to a 300w sub). the sub was pushing outward almost an inch from what it looked like, like something was inside trying to break free, but he had it for over a year, and other than something in his trunk puncturing the sub, its still alive and kicking.
thinkin back, i dont know how he was able to stay calm after something puncturing his sub. i woulda gone crazy.
tyrone slothrop:One question though,- I read in one of the threads that 'Underpowering' is just bs and It's not unhealthy at all to use a lower-powered amp for a stronger sub. Is this true?
That's basically what my last link above said ... The "sweet-spot" is at least 70% of RMS. Going from here to 100-110% RMS only gains you a dB or two (but I usually recommend it). Going from here down to around 40-50% RMS the sub should still work, but it won't hit as loud as it could. Going below 40% RMS, you eventually reach a point where the amp doesn't even have enough power to drive the subwoofer, but you shouldn't damage it.
What usually happens (as I said above) is someone gets a 600W RMS sub and a 400W RMS amp and says "The amp is only 2/3'rds of what the sub is rated for and so I can turn the gain all the way up with no problem. With the gain all the way up, the amp sends a clipped and distorted signal and the sub blows ..."
I remember hearing stories of people blowing their subs with low-powered amps, with the gain at the lowest setting.. I'm not sure though... Anyone?
I don't see this happening - but I can think of three things:
Simply put, as long as you are sending your sub a clean signal (the amp isn't clipping) there is no way that you can blow the sub because you are not sending it enough power.
However, if you have it in a ported enclosure, and you play music that is below the tuning frequency of the box then you can blow the sub with a small amount of power (under RMS). It is also possible to blow a sub if you have it in a box that is too big.
If you are running a ported box, then you will want an amp with a subsonic filter so that you don't have to worry about going under the boxes tuning frequency.
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