interesting question about inside car shaking
11-23-2004, 10:14 PM
#1
1000 Watt CAFz'r
Thread Starter
Join Date: May 2004
Posts: 1,145
HI guys, I have a question about what is it that determines what shakes the hell out of the inside of the car. I have a Jensen A432HLX {yeah I know its crap, even though it has 2x30amp fuses, so dont laugh, its only temporary.) Thats running the sub, and the sub is LOUD, but it dosen't shake the car very well, you know, the seats dont really shake or anything. As well as you can hardly hear it outside the car (when the windows are up), even when pounding hard. Is it raw amp' power that does this? is is there something that I'm missing? Also, what is it that shakes houses and cars as I drive by? is it also raw power? I'm saving up for a Kicker 500SI, would that be a huge improvement? I know if the sub is not in sync with the box tuning, the step response on the sub goes all to hell, and in my experience, I think thats what plays a major role in it, is that true? or is the box/sub issue irrelevent? Any help would be greatly appreciated 
11-24-2004, 12:26 AM
#2
500 Watt CAFz'r
Join Date: May 2004
Posts: 718
your half way on the right path.
the REALLY good systems should shrink your nuts if your listening inside, but your shouldn't hear a sound on the outside (if the windows are closed).
you should only be able to hear/feel the bass when the windows are open (ie the sound escapes) otherwise you want to keep as much sound inside the car. the better the seal around the doors and the tighter the lock - the better it is. also, a more solid car will have less shaking and rattling going on and in turn absorb less of the sound waves = louder sound and more pound inside.
but if your car is solid and sealed up and you still get no pound then you just gotta giv'er and go with some more power and bigger/better sub. if that is no a financial possibility, then try different boxes (ported will usually work best) to try and maixmize your subs output!
good luck!
the REALLY good systems should shrink your nuts if your listening inside, but your shouldn't hear a sound on the outside (if the windows are closed).
you should only be able to hear/feel the bass when the windows are open (ie the sound escapes) otherwise you want to keep as much sound inside the car. the better the seal around the doors and the tighter the lock - the better it is. also, a more solid car will have less shaking and rattling going on and in turn absorb less of the sound waves = louder sound and more pound inside.
but if your car is solid and sealed up and you still get no pound then you just gotta giv'er and go with some more power and bigger/better sub. if that is no a financial possibility, then try different boxes (ported will usually work best) to try and maixmize your subs output!
good luck!
11-24-2004, 08:17 AM
#4
500 Watt CAFz'r
Join Date: Jan 2004
Posts: 609
I found Sub Placement / Firing Direction to play a major part in the car as well.
When running my Sealed Pair of W0's firing forward through the split back seat, there wasn't alot of bass, I upped the amplifier from a MTX Thinder 280 running Mono 2 Ohm to a PA 1600 Stereo 4ohm (250W/side) and yes the subs moved more but the sound didn't increase. Also it was almost un-audible on the outside of the car.
I then turned the same box around firing towards the trunk, the sound increased alot, i achieved alot of shaking inside the car, my visor screws worked them selves out of the roof, my rearview mirror would tilt down if it was really warm out from the shaking.
I then Upgraded the Subs to the W3D6's.. to give 3ohm Load per side of the amp (325W approx) per sub, the intensity came up alot.. but with a sealed box I couldn't achieve anything really good below 40-45hz.
I then had a box built by Brandon (Member) in Oshawa which is approx 5 Cubic feet ported and tuned to around 31 hz, firing back. Its now intense, im heard well before seen on the outside, I have replaced my rear taillight bulbs minimum 3 times now - license plate bulb at least 5 times just from too much vibration. My rear view mirror will fold down off the winshield regardless of the temperature outside, you can see my windows and windshield vibrating while the volume is up, and i had to turn the gain down on the amp as it was just tooo loud.
When i completed my amp rack I noticed alot of excessive air pushing on the fabric brom the trunk to the back seat. I removed the 6x9's to relieve alot of the pressure and once again my volume intensity came way up in the car.
I have tried the ported box firing forward, but it does way-better firing back.
My 2 Cents..
When running my Sealed Pair of W0's firing forward through the split back seat, there wasn't alot of bass, I upped the amplifier from a MTX Thinder 280 running Mono 2 Ohm to a PA 1600 Stereo 4ohm (250W/side) and yes the subs moved more but the sound didn't increase. Also it was almost un-audible on the outside of the car.
I then turned the same box around firing towards the trunk, the sound increased alot, i achieved alot of shaking inside the car, my visor screws worked them selves out of the roof, my rearview mirror would tilt down if it was really warm out from the shaking.
I then Upgraded the Subs to the W3D6's.. to give 3ohm Load per side of the amp (325W approx) per sub, the intensity came up alot.. but with a sealed box I couldn't achieve anything really good below 40-45hz.
I then had a box built by Brandon (Member) in Oshawa which is approx 5 Cubic feet ported and tuned to around 31 hz, firing back. Its now intense, im heard well before seen on the outside, I have replaced my rear taillight bulbs minimum 3 times now - license plate bulb at least 5 times just from too much vibration. My rear view mirror will fold down off the winshield regardless of the temperature outside, you can see my windows and windshield vibrating while the volume is up, and i had to turn the gain down on the amp as it was just tooo loud.
When i completed my amp rack I noticed alot of excessive air pushing on the fabric brom the trunk to the back seat. I removed the 6x9's to relieve alot of the pressure and once again my volume intensity came way up in the car.
I have tried the ported box firing forward, but it does way-better firing back.
My 2 Cents..
11-27-2004, 04:22 PM
#7
every car has a resonant frequence, a frequency which is the loudest in that given vehicle. all u have to do is find it and them make a box t hat will PEAK at that frequency, not be tuned to it but peak at it.
thats how spl works. the loudest note in my car is 52hz, so i make a box tuned somewhere in the mid to low 40's and it peaks at 52hz.
thats how spl works. the loudest note in my car is 52hz, so i make a box tuned somewhere in the mid to low 40's and it peaks at 52hz.
11-28-2004, 01:22 AM
#10
gonna need to find someone with a mic, your local car audio shop might have one. just put your car on the meter and start playing tones, like from 30hz and up one by one and see at which is peaks. say it peaks at 55hz, so then u make a ported box tuned to about 10hz lower than your peak, so 45hz. your box tuning and your peak should be about 10hz apart.
for example my jeep peaks at 52 so my loudest boxes are tuned in 42-44hz region.
for example my jeep peaks at 52 so my loudest boxes are tuned in 42-44hz region.
