Home Theater Subs in a Car?

jfeinman · October 2007

I've got a Velodyne DPS-12 sub, and since I've upgraded my Polk RTi6s in the front of my home theater setup to 2 Polk SDA-2s, the Velodyne is really not all that necessary.

I'm wondering how well it would work in my car, I have a 2005 Subaru Impreza Hatchback. My idea was to leave the sub altogether, perhaps mount the whole box in the back with some angle brackets, and use some sort of power inverter. The amp inside it is 200watts, 400 dynamic. Seems pretty pedestrian when you think of car amp setups, but in my living room, it can get my windows shaking without being cranked too much.

does this seem feasable? Does anyone know of some decent power inverters?

Face · October 2007

Not worth the trouble. Sell it and buy a car amp and sub.

MacLeod · October 2007

The "dynamic" rating is worthless. And knowing home audio, that "200 watts" is likely 100-150. Thats not much at all for a car sub. Anything less than 300 and it just aint gonna get it. Also, its probably crossed over way too high for a car environment. Anything over 80 Hz gets nasty.

Face is right, sell it and buy an entry level car sub and amp. Itll sound and work better than a home sub.

Installer4life · October 2007

I installed a Bose AM5(i think that was the model number) home theather in a Mitsubishi Eclipse in the early 90's. I was all passive so we put in car audio ampifiers to drive the woofer and the cubes. There was no center channel. I can't remember what is sounded like but the customer liked it. If you must use your subwoofer they make inverters large enough to drive it. It would be similar to the ones used in ice cream trucks to run the freezers. I am not sure what electrical system upgrades you might need to run the power inverters. All in all I am with the other guys and can't recommend it.

jfeinman · October 2007

Well, for one, it has a built-in crossover, like most halfway decent subs. I can cut it down to 40hz, and sub has 5 built-in DSP EQ effects. I believe the wattage ratings; this is a Velodyne, not a POS Sony Product. The sub would be in a hatchback, not enclosed in a trunk. Also, don't car subs rely a lot more on the interior air volume of the car, than HT subs do in relation to their rooms when it comes to achieving certain frequencies? Keep in mind that I'm not looking for ghetto blasters. I have never been able to fully crank the sub in my living room, as it gets way louder than anyone can handle, my next door and downstairs neighbors included. And even at the highest levels, I've never heard it clip once.

Sound quality is not what I'm worried about, and it would be really easy for me do try it out. My deck comes out in about 3 minutes, tops. My question is on power inverters. There isn't a UL label on my sub, but should I assume the power draw is about as much as it the wattage specified in the audio specs?
_______________________
Fronts: Polk SDA-2s
Center: Polk CSi-3
Surrounds: Polk RTi6s
Surround Backs: Polk RTi4s
Sub: Velodyne DPS-12
Receiver: Onkyo TX-SR703 (THX Select2)
DVD: Harman Kardon HK-DVD22
Xbox 360
TV: Panasonic 42" PX-75U Plasma

jfeinman · October 2007

Installer4life wrote: »

I installed a Bose AM5(i think that was the model number) home theather in a Mitsubishi Eclipse in the early 90's. I was all passive so we put in car audio ampifiers to drive the woofer and the cubes. There was no center channel. I can't remember what is sounded like but the customer liked it. If you must use your subwoofer they make inverters large enough to drive it. It would be similar to the ones used in ice cream trucks to run the freezers. I am not sure what electrical system upgrades you might need to run the power inverters. All in all I am with the other guys and can't recommend it.

Bose stands for "Buy Other Sound Equipment".

eloplayspolo · October 2007

how can u knock bose, even on the polk forums, I have a 3-2-1 Downstairs in a Massive family room and the thing fills the room with what sounds like a 7.2 system, its amazing, my parents have the bose wave in their bedroom and it sounds pretty freaking stellar, Even the old 301s i heard in my bros best friends house that are about 10 years old sound incredible... ive never heard the polk home theater stuff set up in a room, but i can only hope for polks sake they sound near as good as the bose stuff.

As far as the sub in the car, I tried a POS sony one, and it was a complete joke, as in might as well stuck a 2 year old in the trunk with a mallet and bass drum and said DO WORK SON.

Listen to these guys, they know what they are talking about, sell it, buy a sub and amp.

jfeinman · October 2007

eloplayspolo wrote: »

how can u knock bose, even on the polk forums, I have a 3-2-1 Downstairs in a Massive family room and the thing fills the room with what sounds like a 7.2 system, its amazing, my parents have the bose wave in their bedroom and it sounds pretty freaking stellar, Even the old 301s i heard in my bros best friends house that are about 10 years old sound incredible... ive never heard the polk home theater stuff set up in a room, but i can only hope for polks sake they sound near as good as the bose stuff.

As far as the sub in the car, I tried a POS sony one, and it was a complete joke, as in might as well stuck a 2 year old in the trunk with a mallet and bass drum and said DO WORK SON.

Listen to these guys, they know what they are talking about, sell it, buy a sub and amp.

Thats the problem with people who've only heard Bose in an HT setup. They don't know what they are missing, or how much they got raped up the a$$. Learn something about HT, and read this:

http://www.intellexual.net/bose.html

Listen for voices coming out of your subs, and play a sine-wave test on your system and listen for the huge frequency response gaps. For your info, on the acoustimass or lifestyle 5.1 setups, the cubes have frequency repsonses of 280hz-13khz, with an efficiency raiting of about 83db. The Sub has a response of 46hz-202h.

Whenever I show my customers even a cheap 300 HTIB against the 2000-3000 Bose 5.1 setups, 9 times out of 10, they think the 300 system sounds a lot better.

eloplayspolo · October 2007

im well aware that a 3-2-1 isnt considered a high end surround sound system, but im very picky when it comes to audio, and bose works for me MOST of the time, i dont like those cubes actualy, maybe some of those facts are the reason, but i was watching Lord of War the other day and the tanks and gunfire sounded incredible.

Jstas · October 2007

HT subs don't work in cars because of the environment.

A car sub is usually more robust and the amplifiers carry enough wattage that most HT guys will gasp in wonderment at why you need so much power.

Car environments are much more sonically hostile than a home environment. A Velodyne sub is by no means junk. However, if you throw that sub in a car not only will you not hear it at all but you will not get the response with that you would experience in a much more stable and less noisy home environment.

For you to get the same impact in a car, you need to essentially over-power the space. A car's interior is only a fraction of even the smallest listening room. The sub will not have the space it needs to let the waveforms expand and pressurize the interior of the car. The only way to pressurize the interior and get the same impact is to over-power it and move massive amounts of air. Your home theater sub is not going to do that.

However, if you take a car sub like the DB212-2, throw it in your listening room and strap a 500 watt BASH amp to it, it will throughly thrash your Velodyne in output and completely overpower your listening environment at home. Maybe not quality but it will be loud and the dinky 200 watt amp in your Velodyne will barely have enough guts to make the cones move on that sub box.

Different worlds that are worlds apart dude. Don't waste your time with the Velodyne. If you want the same output in your car, get an SR104 in type 1 small sealed enclosure and throw 400+ watts at it. It'll do much more than your Velodyne ever could being bungee corded in to your truck with a power inverter stuck on it.

BTW, power inverters are VERY dirty AC power. That's usually why you don't see them used for audio equipment unless it's a conversion van or RV.