What to expect from mid size sedan?

[fritosaregood]

yea i was thinking about 5cubic ft after displacment, and not including the the port volume. So if i'm peaking in the 46's what should i tune to? i'm looking for spl so whatever tuning you think would be best to peak at 46hz. I have heard about this thing called resonence frequency responce. it's like your car plays that note loudest. So if my cars resonence frequency is 46's how would i test this ???and how would i tune for best spl. I know it's still going to require some trial and a few boxes befor i hit a 155 but i know it can be done .

If your sure your car peaks at 46hz, then you should tune around that.

if you have access to a termlab you can build a box with an external aero port. start it tuned around 40 or so and cut it down about a half inch at a time until it peaks. then find out the tuning right there. and build to that.

Id say a test box with 2 or 3 6in aeroports would be good and give you a nice amount of port area.

trial and error will give you the best results.

that was my first box i designed for the 18. it took me about 5 boxes for my last 15 before i got it doing good numbers.

[doeboi_79]

If your sure your car peaks at 46hz, then you should tune around that.

if you have access to a termlab you can build a box with an external aero port. start it tuned around 40 or so and cut it down about a half inch at a time until it peaks. then find out the tuning right there. and build to that.

Id say a test box with 2 or 3 6in aeroports would be good and give you a nice amount of port area.

trial and error will give you the best results.

that was my first box i designed for the 18. it took me about 5 boxes for my last 15 before i got it doing good numbers.

thanks again for the help. so this is what i'm going to do , 5.0cubic ft box walled to the back seat firing forwared into the cab of the car. an external port 2 6" flared ports. tuned to 38hz then run test tone to find my best frequency. does that sound right? again thanks for the help.

[Boon]

yea i was thinking about 5cubic ft after displacment, and not including the the port volume. So if i'm peaking in the 46's what should i tune to? i'm looking for spl so whatever tuning you think would be best to peak at 46hz. I have heard about this thing called resonence frequency responce. it's like your car plays that note loudest. So if my cars resonence frequency is 46's how would i test this ???and how would i tune for best spl. I know it's still going to require some trial and a few boxes befor i hit a 155 but i know it can be done .

Dude if you're asking these questions you're one hell of a long way off a 155, gonna be more than a few boxes involved. If you wanna stay in the trunk start looking into 10kw amps and some extremely powerful subwoofers. DDZ type woofers.

I reckon a 155 from the trunk is gonna take you at least 10kw and a few years.

I hate to be negative (who am I kidding, I love it) but I've only just broken 150 at that kind of frequency and it took a couple of years, a bunch of 15" subs in a half-wall and about 8kw of power.

[doeboi_79]

Dude if you're asking these questions you're one hell of a long way off a 155, gonna be more than a few boxes involved. If you wanna stay in the trunk start looking into 10kw amps and some extremely powerful subwoofers. DDZ type woofers.

I reckon a 155 from the trunk is gonna take you at least 10kw and a few years.

I hate to be negative (who am I kidding, I love it) but I've only just broken 150 at that kind of frequency and it took a couple of years, a bunch of 15" subs in a half-wall and about 8kw of power.

thanks for your 2 cents , but I have only been doing spl for about 6 months and hit a 145. already and thats non walled out my trunk on music with a stalk alt. looks like some people learn faster than you. not tring to be rude, or am I .

[fritosaregood]

thanks again for the help. so this is what i'm going to do , 5.0cubic ft box walled to the back seat firing forwared into the cab of the car. an external port 2 6" flared ports. tuned to 38hz then run test tone to find my best frequency. does that sound right? again thanks for the help.

i wouldnt wall a 5 cube box. you could try to fit it in the trunk and fire to ports forward. or have the box in the backseat and fire the ports to the rear.

after you find your peak when your box is at 38hz, cut the ports a little shorter and try again.

[doeboi_79]

i wouldnt wall a 5 cube box. you could try to fit it in the trunk and fire to ports forward. or have the box in the backseat and fire the ports to the rear.

after you find your peak when your box is at 38hz, cut the ports a little shorter and try again.

thanks for all the help , I have a lot to do befor the next comp in may.

[Boon]

looks like some people learn faster than you. not tring to be rude, or am I .

Mega edit power:

Right, ranting asshole time:

Shit, I suspect I'm being called out here.

I have a 150dB daily driver. Where's yours? I will modestly say that I know my shit.

First post I was just trying to keep your expectations realistic but now I'm gonna be an asshole (like usual) and say it straight up - you're not gonna do a 155 out of the trunk with less than 10kwrms. And if you have to ask an internet forum how to tune to your car's resonant frequency it's gonna be a long fucking time until you do hit that 155 even if you do get 10kw of power from somewhere.

P.S. To complete my assholery, the scores in your sig are all decidedly average, I got louder with 2 8's and 600wrms.

Double edit, I suspect I'm like half your age, which makes you the slow learner

[doeboi_79]

Mega edit power:

Right, ranting asshole time:

Shit, I suspect I'm being called out here.

I have a 150dB daily driver. Where's yours? I will modestly say that I know my shit.

First post I was just trying to keep your expectations realistic but now I'm gonna be an asshole (like usual) and say it straight up - you're not gonna do a 155 out of the trunk with less than 10kwrms. And if you have to ask an internet forum how to tune to your car's resonant frequency it's gonna be a long fucking time until you do hit that 155 even if you do get 10kw of power from somewhere.

P.S. To complete my assholery, the scores in your sig are all decidedly average, I got louder with 2 8's and 600wrms.

Double edit, I suspect I'm like half your age, which makes you the slow learner

aw you got salty. I'll hit 150 before the end of the year, hopefully a 155. Are you doubting I can do it? well that will just make me try harder.The fact of the matter is I have only been doing SPL for a short time. But i hit a 145 on music in a car with no deadening , no HO alt,and only 4k . You really don't think I'll hit my goal? let's make some sort of bet.

edited, for spelling , you should try it.

[Boon]

aw you got salty. I'll hit 150 before the end of the year, hopefully a 155. Are you doubting I can do it? well that will just make me try harder.The fact of the matter is I have only been doing SPL for a short time. But i hit a 145 on music in a car with no deadening , no HO alt,and only 4k . You really don't think I'll hit my goal? let's make some sort of bet.

edited, for spelling , you should try it.

Yeeeap ok. (By the way, spelling errors? Care to point them out captain literacy?)

I'll put $100 on it. 155 by the end of the year, out of the trunk. Legal, dbdrag termlab, on the dash sealed up, at an official event.

Where you claim about your 145 with no deadening and no HO alt just shows your naivety when it comes to big stuff like this. Deadening may lose you dB. An HO alt won't gain you much either. Maybe 1dB. And a 145 with no deadener and 'only' 4kw is nothing spectacular. Gaining 10db means you'll need approximately 10 times as much energy at the meter. (3dB is a doubling in acoustic energy, then allow for losses in efficiency)

So mathematically you would need to go from 4kw to 40kw with whatever got you your 145.

I'm thinking my money is pretty safe, to be honest. And if you do manage it, good for you, my $100 can offset the $8k you spent on equipment to get there.

[doeboi_79]

Yeeeap ok. (By the way, spelling errors? Care to point them out captain literacy?)

I'll put $100 on it. 155 by the end of the year, out of the trunk. Legal, dbdrag termlab, on the dash sealed up, at an official event.

Where you claim about your 145 with no deadening and no HO alt just shows your naivety when it comes to big stuff like this. Deadening may lose you dB. An HO alt won't gain you much either. Maybe 1dB. And a 145 with no deadener and 'only' 4kw is nothing spectacular. Gaining 10db means you'll need approximately 10 times as much energy at the meter. (3dB is a doubling in acoustic energy, then allow for losses in efficiency)

So mathematically you would need to go from 4kw to 40kw with whatever got you your 145.

I'm thinking my money is pretty safe, to be honest. And if you do manage it, good for you, my $100 can offset the $8k you spent on equipment to get there.

Well if you really want to bet that's cool with me. But not 155db let me break 150db first. A bet I'm willing to make is ,150 at the dash by the end of this year. On this I would bet 100$ no problem. But it's up to you man. I don't see why you would doubt me. Just because i asked dude some questions???