This question is probably very hard to answer, but I'd just like a ballpark number. where SHOULD I be hitting decible wise with one Infinity 300 watt RMS 1000 watt max subwoofer, 2 kenwood 600 watt max 6 x9's (off of HU), 2 legacy 3.5 inch 300 watt max speakers in an El Camino (you know the truck/car)? I understand if this cannot be answered, I was just inquiring out of curiosity b4 I take it to get tested.
what amp do you have pushing the sub and how is the sub sitting and in what kind of enclosure? You can get a SPL meter at radio shack for cheap, btw.
JonK
Unregistered guest
Posted on
Hey, thanks a lot steve...My sub is in a prefab 12" sub box I think about 1.5 cubic feet or something close to that...My amp is a real piece of crap I bought on Ebay Mitzu 2000 watt max 4 channel with two channels bridged to my sub...that's why I was wondering what I should be hitting because I may need to get a better sub if I'm not even close to what I should be...thanks again
JonK
Unregistered guest
Posted on
sorry, I didn't mean to say "new sub" I meant to say that I may need to get a new amp...my bad
o hell no....you have one of those cuspid amps...i got one from a friend of mine 1600watts that thing would barely move my 1230w and when i hooked it up to my 9500 it didnt do anything...throw that sh!t away please
here's a though...Start with the sub's rated sensitivity. Thats at one watt. Every time you double the power going to it, the SPL should increase by about 3db. So for example, If the sub is rated at 90 db (1 watt @ 1 meter) If it was getting 300 watts, the spl should be about about 115 decibals at 1 meter away (not with the car closed up). Thats about as good an estimate as you'll be able to get online. Also, you didn't say if the prefab enclosure is ported or sealed. That could make about another 3db difference.
"Start with the sub's rated sensitivity. Thats at one watt. Every time you double the power going to it, the SPL should increase by about 3db. So for example, If the sub is rated at 90 db (1 watt @ 1 meter) If it was getting 300 watts, the spl should be about about 115 decibals at 1 meter away (not with the car closed up). "
That number could be so far off... You do realize that doesn't take into account the enclosure, the vehicle's cabin gain, and lastly, yes companies can fudge the sensitivity ratings. They use different methods to test it, and can in effect change the test untill they get a number that looks good.
Joe, I said in my post that that estimate didn't account for the enclosure type or for it being in the car. Also, he obviously can't test for the sensitivity of the sub if he can't bench test it to find out how much spl it should be putting out at full power. He wanted to know if his amp was powering it sufficiently. If he tested it and only got 97 db out of it, he'll know what that means. He asked for a ROUGH estimate, and thats what i gave him, knowing full well that it could be off by +/- 10 db or so.
you realize 10dB is two to four times the audible volume, and a difference of as much as 10 times the power.. that's a BIG buffer zone there.. That's like saying well, you'll have the output of running somewhere between 1000 and 10,000 watts.. give or take.
also that estimate doesn't account for excursion of driver displacement, or power applied.. it's really not accurate at all.. not even roughly.
He asked for a rough estimate, granted mine is bad, but I still haven't seen you give him one glass...
JonK
Unregistered guest
Posted on
whoa! stop fighting...Scuba's answer was more than sufficient for me...and I appreciate it very much...I just wanted to know if my amp was coming even close to pushing my sub...thanks scuba!
JonK
Unregistered guest
Posted on
I also found out that there is a really cool car stereo place in town called Car Stereo One, and if you wait for the right time, you can get a pretty good deal on a good amplifier. So, it becomes a waiting game....
the problem is steve's answer was completely wrong. there's no way to even guess at your SPL without getting it metered. far too many variables he didn't even bother to consider. that's WHY I didn't guess.
a sub's sensitivity isn't going to tell you anything about teh SPL score you'll hit in a given application, by itself. Period. No more so than the miles per gallon rating of a car's engine will tell you how fast it'll be in a quarter mile.
because your way isn't a way of estimating anything. it's just as accurate as pulling a number out of thin air. That's the point, steve. The enclosure can make a +/-15dB difference alone. Add to that the number of subs, cabin gain, power used, enclosure location and positioning, and you really have no earthly way of knowing what he'd hit.. that's all I'm trying to point out.
He won't know what he'll hit till it's metered. Giving people false ideas of estimates will lead to people posting ficticious numbers based on guesses at their SPL based on your estimations. I'd rather stick to as much objective data as possible when it comes to things like SPL, since that's one thing people seem to be really @nal about in regards to acuracy and how "objective" it is in competiton compared to SQ events.. (watch any argument between a SQ guy and an SPL guy hehe)
anyway, I made my case. I'll just leave it at that. he can do as he pleases. I'd love to see what he meters though when he gets read officially.
glass is right, you can't even begin to guess what your DB's will be
its 130 DB, now go get it tested and see how close i was, haha the point i think were all tryint to make here is, go get it tested
JonK
Unregistered guest
Posted on
Well boys, you'll have to wait until next week to find out because I'm busy this weekend. But I do plan on taking it to get tested...I would have taken it today, but I noticed that my muffler rusted off of my car, and now I have to fix that...Keep an eye out though for a post of my Db reading...
