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Discussion Starter #1
i have been looking to get some new subs recently but i was unsure if underpowering would effect SQ of the subs

i will be getting a kenwood excelon x1200m it is supose to push 1200rms and its CEA rate but im banking that i will push around 1100 give or take.

optimaly i would want 2 600rms subs (i think) but i have been looking at some subs that are 750rms.....if the amp actually pushed 1200 i would be 300 short but im sure ill be more in the 400 range...

so Back to my OP would it effect much? and if not could someone enlighten me a little.......i still have alot to learn
 

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i have been looking to get some new subs recently but i was unsure if underpowering would effect SQ of the subs

i will be getting a kenwood excelon x1200m it is supose to push 1200rms and its CEA rate but im banking that i will push around 1100 give or take.

optimaly i would want 2 600rms subs (i think) but i have been looking at some subs that are 750rms.....if the amp actually pushed 1200 i would be 300 short but im sure ill be more in the 400 range...

so Back to my OP would it effect much? and if not could someone enlighten me a little.......i still have alot to learn
I would be more worried about running that amp at 1 ohm for affecting SQ then coming up a few hundred watts short of sub specs.
 

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I would be more worried about running that amp at 1 ohm for affecting SQ then coming up a few hundred watts short of sub specs.
I agree.

Under-powering subs is never a bad thing unless you're worried about tenths of decibels being lost in the SPL lanes. Power handling is a limit, not a requirement.
 

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I agree.

Under-powering subs is never a bad thing unless you're worried about tenths of decibels being lost in the SPL lanes. Power handling is a limit, not a requirement.
I have read many times on this forum that under-powering is worse than over-powering. Perhaps those discussions were concerning MAJORLY over powering a sub (i.e. sending 65w to a 500 w RMS sub)??

I am surprised to read the above responses (not that I disagree), so I am curious as well. I agree that pushing the amp to 1-ohm is something to consider when looking at SQ.
 

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The main problem with individuals underpowering their subwoofers is that they tend to overdrive the amp that is powering the subwoofer because their bass is lacking. There are all kinds of creative ways they over drive the amp, such as: Bass control maxed out on the HU, Loudness enabled, bass boost maxed out on the amp, and gains maxed out.

I am sure many of us have heard our share of kids distorting the hell out of their subwoofers thinking it sounds "badass". Yes it sounds bad and yes it sounds like ass but not in a good way! Regardless, after hearing my neighbor's son's truck, I wholeheartedly agree that some people don't hear distortion until it is 30% or more! Also, those nice square waveforms being sent to the subwoofer will ruin them over time with all of the excess heat produced in the voice coil by overdriving the amplifier.
 

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The main problem with individuals underpowering their subwoofers is that they tend to overdrive the amp that is powering the subwoofer because their bass is lacking. There are all kinds of creative ways they over drive the amp, such as: Bass control maxed out on the HU, Loudness enabled, bass boost maxed out on the amp, and gains maxed out.

I am sure many of us have heard our share of kids distorting the hell out of their subwoofers thinking it sounds "badass". Yes it sounds bad and yes it sounds like ass but not in a good way! Regardless, after hearing my neighbor's son's truck, I wholeheartedly agree that some people don't hear distortion until it is 30% or more! Also, those nice square waveforms being sent to the subwoofer will ruin them over time with all of the excess heat produced in the voice coil by overdriving the amplifier.
It's not exactly the shape of the waves that ruin the subwoofer - it's the excess power and the frequencies within that excess power. For instance, if an amplifier is rated at 100 watts and it will do a MAX of 300 watts fully clipped and you put it on a subwoofer system that is rated for 600 watts, more-than-likely you will not blow that subwoofer.

Under-powering subwoofers is perfectly fine. Especially if you're talking about under-powering from a RMS rating standpoint. Rated power handling should be, but isn't always the case unfortunately, a power handling limit of the subwoofer in its recommended enclosure whether it be mechanical or thermal. Afterall, people just want to know how much it can handle. They typically don't care if it's mechanical or thermal...just at what point does it break.

GunForHire posted up a good thread over on our forum that reads:

Sorry for the mini-techincal rant, but this old lie needs to be put to bed...

SO many people claim that a clipped signal kills speakers because it "sends DC" to the speaker which kills it. NOTHING COULD BE FURTHER FROM THE TRUTH!

A square wave is a summation of sine waves - pure and simple. Additionally, it does NOT have any components below the fundamental of the square wave!

Take a 40 Hz square wave - the LOWEST frequency component it will have is 40 Hz. And it will have frequency components ABOVE that point but NONE below.

Take a 40 Hz sine wave, and clip it. You add higher frequencies to it. THESE HIGHER FREQUENCIES are what contain the extra power. In fact, the average power of a sine wave is 1/2 its peak power (for example, assume you have a 50V peak signal into a 4 Ohm load - that is 50*50/4 = 625W peak, or 312.5W average). A square wave though - because of the higher harmonics - has an average power EQUAL to the peak power (fully clipped, that 50V sine wave would deliver 625W average).

So, to summarize - CLIPPING DOES NOT CREATE A DC COMPONENT - EVER!

OK, I feel better...
Unfortunately a lot of the car audio consumers are consumed with purchasing a driver rated at 600 watts and thinking it will be OK with 1200 watts. And if it doesn't handle the power, that means the subwoofer is a POS. All of you have seen it; "I know the sub is rated at 1000 watts, but I've got 1800 - can it handle it daily?" And, IMO, that (a summation of years worth of marketing BS and/or improper rating of subwoofers just so people don't blow them) is the reason why a lot of people pick a subwoofer that handles an amount of power really really close to the amount of power that they have available and then they over-drive the amplifier and end up cooking their subwoofer.
 

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Discussion Starter #7
ok now that i can finaly reply (for some reason i havnt been able to reply it says i cant so w/e) ok now from what iv gather from every one....over powering the sub would not hurt it if it was a good sub..and the amp wasnt cliping...
underpowering a sub can be bad cause you are probably overdriving your amp..

a buch of other confusing stuffs but thats what ive gathered ..as well as woried about a 1 ohm load..

now im confused about the 1 ohm laod thing..."if" i got the 12" solobaric L7's..2008model....they are rated at 750rms.....i would be getting TWO of these both 4 Ohm DVC...

so my load would only be a 2ohm load not a 1 ohm load...
my amp will be (backed up shiping -,-) a Kenwood excelong x1200m it is rated at 1200rms @ 2ohms and it is 1 ohm stable (and yes iv seen 1ohm stable amps go sizzle poof)

i nvr turn my gain up more than 85% i normaly keep it in the 70-80% range...and on my HU i "may" have my lows up to 4-5 (out of 10)

as for the "sub" setting on my HU i keep it at 0 or turn it down to the negatives...anything higher always sounded like crap and it was to over bearing

so in summary
2 4ohm DVC Kicker SoloBaric L7's rated at 750rms each, hooked up in parallel and as far as i know bridged...giving me a 2ohm load
this would be hooked up to a Kenwood excelon x1200m amp its a mono block rated at 1200rms the gain woul be 70-80% up (guessing, may be lower need to hear it..this is my first "real" amp soo...)


i have not bought these subs yet but im considering it but i needed to make sure it would be fine and not blow up anything
 

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Perfect response and quotations, Electrodynamic. Took the words out of my mouth :)
 

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i have been looking to get some new subs recently but i was unsure if underpowering would effect SQ of the subs
They will sound great just quietly ;)

Now if you do what over 6,000,000,000,000,000 people have done before you, which is clip the bejesus out of your amplifier since you can't hear the distortion at those frequencies very well.

We'll talk again :)
 

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And, IMO, that (a summation of years worth of marketing BS and/or improper rating of subwoofers just so people don't blow them) is the reason why a lot of people pick a subwoofer that handles an amount of power really really close to the amount of power that they have available and then they over-drive the amplifier and end up cooking their subwoofer.
So the fact that I picked a DLS A6 monoblock amplifier, rated at 500 w RMS at 4 ohm to be paired with a single Sound Splinter Rl-10i SVC which is rated at 500w was a bad idea? Especially if I am unable to hear the clipping? I know it is more complicated than that....but in jist, did I go wrong? I did nto purchase them based on marketing hype, but rather on reading many threads that seemed to indicate this type of paring was a best practice. I also followed the SS mfr. recommendations of a sealed enclosure of 0.65 cubic inches.

To me it sounds pretty good. Additionally, I am not a bass blaster. I do throw in the occasional Digital Bass 305 CD to feel the bass in my backside....I cheat on my SQ wife with my SPL mistress...but not often!:D
 

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Discussion Starter #12
So the fact that I picked a DLS A6 monoblock amplifier, rated at 500 w RMS at 4 ohm to be paired with a single Sound Splinter Rl-10i SVC which is rated at 500w was a bad idea? Especially if I am unable to hear the clipping? I know it is more complicated than that....but in jist, did I go wrong? I did nto purchase them based on marketing hype, but rather on reading many threads that seemed to indicate this type of paring was a best practice. I also followed the SS mfr. recommendations of a sealed enclosure of 0.65 cubic inches.

To me it sounds pretty good. Additionally, I am not a bass blaster. I do throw in the occasional Digital Bass 305 CD to feel the bass in my backside....I cheat on my SQ wife with my SPL mistress...but not often!:D
from my understanding if you have a GOOD sub its better to throw more power at it then the same or lower cause u can clip....but if it works it works i guess
 

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So the fact that I picked a DLS A6 monoblock amplifier, rated at 500 w RMS at 4 ohm to be paired with a single Sound Splinter Rl-10i SVC which is rated at 500w was a bad idea? Especially if I am unable to hear the clipping? I know it is more complicated than that....but in jist, did I go wrong? I did nto purchase them based on marketing hype, but rather on reading many threads that seemed to indicate this type of paring was a best practice. I also followed the SS mfr. recommendations of a sealed enclosure of 0.65 cubic inches.

To me it sounds pretty good. Additionally, I am not a bass blaster. I do throw in the occasional Digital Bass 305 CD to feel the bass in my backside....I cheat on my SQ wife with my SPL mistress...but not often!:D
You're not over-driving your amplifier and you seem to know what you're talking about, so it's not a bad thing. The last part of my reply was key. :cool: What I said was that a lot of the industry rates their drivers for less than they will handle because they anticipate people throwing more power on them than they're rated for even if they don't know they're doing it. If you buy a sub rated for 600 watts and buy a 600 watt amp and clip the bejesus out of it and send your driver 800+ watts don't wonder why it didn't handle the power. That's all I was saying. Heck, I run twin SAZ-1000D's strapped on my pair of Mag v4's in 1.3 cubes each. But I set up the amplifiers properly and I know when to turn it down. :)
 

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If I hooked up my PA amps my sub would last seconds at best.

Although i did test it in a small sealed enclosure with a bridged PM350
 

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I can't really think of a PA amp that's rated to one ohm, even per channel, other than a Crown Grounded Bridge design in parallel mono, and in the 2250 range that would be a MT2400, MA2400, or MA2402, or possibly an old PB3.
 

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Yeah...haven't seen a PA amp rated that low in years if ever. No reason to with 120V mains...
 

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Jeez man why go 120V when you can buy a couple kilowatt of 12V amp for chree-fiddy any hour ;)
 
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