I currently have the JL Audio stealthbox under the 60 portion of my 60/40 rear seats... the amplifier is laying flat under the other 40 portion of it. I'm considering building and carpeting a to match a basic little storage box to hold jumper cables, spare flashlight, and a few basic tools... but I don't want to place it over the amp if the amp is going to be too hot! I realize the amp does need some air so I was planning on placing the box about 1/4-1/2" above the amplfier so air could get in and circulate and stuff, just wondering if anyone else had done this?

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Matt Adams
Littleton, CO
1994 Ford Explorer, highly modified ( http://bart.is-s.com/~explorers/madams/ )
2000 F-150 XLT Supercab
5.4L Triton V8 Engine
Automatic Transmission
3" dual exhaust
Rhino lining
K&N Filtercharger Intake Performance Kit (FIPK)
JL Audio stealthbox with Phoenix gold amplifier, premium stereo
Genuine Steel brush guard with 4 PIAA 520's mounted on it
PIAA Airdam with PIAA 520 fog's and PIAA 510 superwhite driving lights in it.
Genuine Steel brushguard with 4 PIAA 80 XT's (2 fog's, 2 drivings) mounted on it
off-road and tow packages
and much much more! (no page yet)
Soon to come:
Roll bar with 3 sets of PIAA 80 XT's mounted on it
Storage box in the back

 

Amps _can get really hot. I can't tell from your question whether your worried about how hot the amp will get for the amps sake or the stuff in your box's sake. If it's the later I don't really think the amp will heat up the air under the storage box enough to cook anything in it. But you do need to be careful and give the amp plenty of room to breathe. 1/2" will probably be okay. I know fosgate recommneds 1" of air above their amps. I have my 6 year old Punch 60 under my drivers seat mounted on two small pieces of wood to allow air both under and above the amp. I also have it bridged down to 2ohms mono running 2 10s. I gets hot enough to burn you, but never shuts off. Gotta love the old Fosgate stuff...

 

As the above post noted, you do need to leave some space for air movement. If you're worried about heating up too much, then just place a small fan (available from Radio Shack....brushless) to pull air over the heatsink. With the fan, you won't need to worry about heat as long as you leave a small path for air flow.

 

hey guys thanks for the help... I'm more worried about the heat of the amp then the heat of the contents of the box. I may do what you recommend adn try to leave a 1/2"-1" of airspace above it. I'm not sure if the amount of bass you use is relational to how hot the amp gets, but I have the bass set just about as low as it goes... I may just try and put my hand on the amp after a while with the stereo on and see how hot it gets... this box wouldn't be very large obviously, jsut enough to hold jumper cables, maybe a tow strap and a few misc. items.

 

Just for directional discussion -- assume that an amp is 50% efficient -- meaning that if you're running 250 watts at 50% efficiency -- then an additional 250 watts is being wasted as heat -- and a 250 watt bulb makes, well, 250 watts of heat that needs to be displaced somewhere.

Using the above ratio -- figure out how big a light bulb would be needed to account for the wasted heat -- and then plan on enough cooling so that you'd be comfortable with a light-bulb of that wattage under your seat.

 

Also, there are different classes of amps. Class D I believe is the best. Class D amps have an efficiency of 80% or better. I have a class D amp pushing around 1000W at 1 ohm to 2 12" subs. The amp gets warm when played long periods of time.

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1998 F150 S/C
4.6 V8
Flowmaster 40 muffler
Sony CDX-C7850 CD Player
2 12" DEI Competition subs
DEI 1100D amp
4 kicker Impulse 5x7
Legacy LA360 amp
Expy console

SOON TO COME!!
Sony XE-744 Equalizer

 

What if you wired a muffin fan in the box like they've got in computers? They use no power are quiet, and I'm pretty sure they run at 12v.

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2001 Lariat SC 5.4 4x4 LS ORP Class III 17in wheels Captains seats

Sony ES CDX-M650 Polk EX572a(2 pr.) Dynamats

Westin nerf bar, ARE Z series cap, Yakima rack, Bedrug

Superchip

PIAA 520 driving lights behind grill
PIAA 1400 fogs in bumper intakes

 

Amps do need air. A simple a quick fix would be to get one or two small electronic cooling fans, similar to those found in your computer. They are small, and come in various sizes, but the 2"-4" range would work good.

 

A "Class A" amp is the best type of amp around. It will give the best sound for pushing the speakers and is the most efficient when using the power from the power supply.

Have Fun & Keep on Truckin'
Dean

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1994 F-150 XLT Supercab, Long Box, 302 EFI, 3.55 LS, K&N FIPK, Bosch Platinum +4 Spark Plugs, Automatic, Single Catalytic converter, followed by a Raven Z-55 muffler and finished off with chrome tips (2 1/2" to 3"), Royal Blue in and out, Captain Chairs. Chrome Rims 15x8's, Michelin LTX M/S 105S 235/75R15 (Summer), OEM Aluminum Rims 15x8's, Michelin LTX M/S 108S (Winter), Lightly Tinted, Soft Tonneau Cover, Ford Receiver Hitch Cover & Lock, J&J Enterprises Stainless Steel AirDam with KC driving lights, Lund Supersteps, Lighted Grab Bars, VTech Slotted Taillight Covers, Alpine CDM-7829 Head Unit, PPI 4800 Amplifier, Kicker 10" Solo Baric Sub with Custom Box and Kicker Impulse 6.5 Mid & Tweets.

 

If you decide to use a fan, try to find a brushless 12v. Others can give you noise injected into you system.