LS400 tips & tricks

[1980supreme 10+ year member]

I've got a 93 ls400 and for those that've worked on them, you know they've got a firewall behind the rear seats because the gas tank is in the trunk...

The sub setup that I'm running is a 10" DC level 5 (thorshammer's) and a gold American Bass vfl 150.1

It's quieter in this car than any other car i've had it in... Right now the port and sub are on the same side and facing the rear of the vehicle.

Do i point the port at the hole in the rear deck from the factory sub?

Do i make a forward firing sub box? I'm not sure where to go with this...

not sure where to go with this...

Click to read more...

 

[Bass911 10+ year member]

Remove the 8 inch factory sub and face the box to the back. The bass will come in the car through the opening where you removed the 8 inch factory sub.

 

[1980supreme 10+ year member]

I already have... that was the first thing i did. compared to trunk cars without the firewall, its just not as loud.

 

[blazian87 10+ year member]

I already have... that was the first thing i did. compared to trunk cars without the firewall, its just not as loud.

Have you thought of putting a bigger sub? it's hard to get a 10" loud in that type of car. How big is your box @ what tuning? So you say there's a firewall behind the seats as in you can't fit a sub there? Sub and port firing forward sealed off edges would make it louder if you can physically do that. Going with more cone area if you have the space can easily make you louder too.

 

[1980supreme 10+ year member]

the firewall is just a factory sheet of metal behind the seats. the only hole from the trunk into the cabin is where the factory sub was in the rear deck... I'm torn on the bigger sub... the level 5 gets pretty loud, i might just be expecting too much. in other vehicles, it's pretty impressive for a 10 on 2500 watts.

The box is 2.25 cubes at 32hz just an ordinary slot port

 

[blazian87 10+ year member]

the firewall is just a factory sheet of metal behind the seats. the only hole from the trunk into the cabin is where the factory sub was in the rear deck... I'm torn on the bigger sub... the level 5 gets pretty loud, i might just be expecting too much. in other vehicles, it's pretty impressive for a 10 on 2500 watts.
The box is 2.25 cubes at 32hz just an ordinary slot port

hmm.. where exactly is the factory sub? I'm having a hard time picturing this. Do you have any pics of the area by any chance? I'm sure your single 10 is very impressive for what it is but you're still limited with cone area. 2 12's or 1 badazz 15 can get you louder easier. Unless you could somehow put a 2nd 10" Level 5 with 2nd amp strapped, and beef up your electrical even more. That's an expensive route though.

I pulled up a diagram of your car.. Looks like you're very limited. Only thing I could think of is cutting a hole somewhere in your rear deck and have the sub facing up.

 

[1980supreme 10+ year member]

this is what i mean... doesn't leave a lot of options

 

[blazian87 10+ year member]

this is what i mean... doesn't leave a lot of options

I see, I see.. So what is the top hole in the rear deck for? Is it supposed to be the factory sub location? Yeah, it doesn't leave you with many options because that wall is physically blocking most of the bass from coming inside the cabin. Would you consider putting the enclosure in your back seats area? That would work but it may attract thieves. You can tint your windows if you're worried about that. Otherwise the only thing I can think of is using the top hole and mounting a sub in there with Infinite baffle. Looks like everything else is sealed up good that's why. If you're willing to cut a big square hole and make a thick subwoofer baffle with wood, seal it up good, then all the bass would go right into your cabin. Another idea is making a 4th order bandpass box.. The box would be in your trunk, sub facing up, then the bandpass part can be connected with a long sonotube or aeroport. The sound would also go directly into your cabin and your SPL would go up tremendously.

 

[1980supreme 10+ year member]

I use my back seats too often to consider losing them...

The top hole in the rear deck is for the factory sub.

the reason that the wall is there, is that the factory gas tank is right behind it. If i was in a bad crash, i'd have gasoline inside the car. there's nowhere to relocate the tank and i'd lose rigidity in the body if i cut the rear firewall as well as some degree of safety... it's not really worth it.

I've never really considered a bandpass box because they're harder to design and get a flat response, but i'll do some reading.

 

[supra1987]

the only thing I can think of is using the top hole and mounting a sub in there with Infinite baffle. Looks like everything else is sealed up good that's why. If you're willing to cut a big square hole and make a thick subwoofer baffle with wood, seal it up good, then all the bass would go right into your cabin.

sounds like best option not having to change any equipment.

 

[blazian87 10+ year member]

I use my back seats too often to consider losing them...
The top hole in the rear deck is for the factory sub.

the reason that the wall is there, is that the factory gas tank is right behind it. If i was in a bad crash, i'd have gasoline inside the car. there's nowhere to relocate the tank and i'd lose rigidity in the body if i cut the rear firewall as well as some degree of safety... it's not really worth it.

I've never really considered a bandpass box because they're harder to design and get a flat response, but i'll do some reading.

Yea I understand that. I'm not saying you have to cut through the rear wall as that would be a safety hazard. I was just saying making the factory sub hole bigger to fit your sub in. In an IB setup, your whole trunk would act as an enclosure so it's practically like a giant sealed box. The curve will be very flat and efficiency is pretty impressive. The sub would be facing up and be reflecting off the back window which is sure to give you an increase in spl and still maintain great sq. I can imagine it getting loud because right now the bass is trapped in your trunk essentially. It needs to make its way to the inside of the car. That's also why I suggested a 4th order. It would transfer all the sound inside through a port and be super efficient. Yea it is more difficult to design one that will play flat. Most people tune high with it because they want spl but I've actually seen some people tune low. I've heard people either do 50/50 or 1/3 for sealed and 2/3 for port. I'm no expert though so you would have to ask around for that. If anything, having a professional design it for you would be your best bet.

 

[will3 10+ year member]

Just a heads up if you get hit hard enough in the rear section of this car there will be gas in the cabin anyway, I have seen it happen already, but a 4th order blown through the deck is your best 2 nd best option to changing cars