Toasted My Amp

[faceliftedss]

i had a 3000 watt monoblock class D amp hooked up to two 8 ohm 10" in series making it 4 ohms. and two 12" 8 ohm also in series making that 2 ohms over all. the amp is rated to put out 1500 rms at 2 ohms and also it has it's own cooling fans. any time i would turn my bass up really loud it would shut itself off after a while but it would work like normal if i turned my HU off and then back on, except this time. the amp was connected using 4 guage power and ground wire, could this have been the problem?

[fast4popper]

i had a 3000 watt monoblock class D amp hooked up to two 8 ohm 10" in series making it 4 ohms. and two 12" 8 ohm also in series making that 2 ohms over all. the amp is rated to put out 1500 rms at 2 ohms and also it has it's own cooling fans. any time i would turn my bass up really loud it would shut itself off after a while but it would work like normal if i turned my HU off and then back on, except this time. the amp was connected using 4 guage power and ground wire, could this have been the problem?

 

first give me brand of this 3000watt amp. if its trully 3000 watts it should have needed 0 gauge wire. or at very least dual 4 gauge. also, where is it grounded? get me these answers and i more than like will have a solution. but my guess is you starved it for input voltage.

[Chevrolet SS]

4- 8ohm speakers seried is 32ohm.......................

[faceliftedss]

im sorry i meant parallel. ohms law for resistors in parallel is a * B / a + b so 2 at 64/16=4 and combining those 16/8= 2.

 

i do doubt that it was putting out 3000w max

yeah my guess is it was starved for power. but just wanted a second oppinion.

[misterp]

first give me brand of this 3000watt amp. if its trully 3000 watts it should have needed 0 gauge wire. or at very least dual 4 gauge. also, where is it grounded? get me these answers and i more than like will have a solution. but my guess is you starved it for input voltage.

As an example, my Orion class-D has two 4-guage power leads, with a 150-amp fuse on each lead (yes that's 300 AMPS, as in I have to run a 300-amp alternator just for this one amplifier by itself for a burp); from the fusing that's 300 amps * 14.4 volts = 4320 watts of primary power, and if the amplifier is 85% efficient (a wild-assed guess) then 85% of that incoming power will actually make it to the speaker = 4320 * 0.85 = 3672 watts. Also remember that you will have to move that 300A current from the alternator to the amplifier and that is a distance of about 14-18 feet (depending on cable routing) so to safely move 300A current that distance requires 2/0 cable minimum if you want to keep voltage drop to an acceptable level. This is just to give you an idea of what it takes to power an honest 3,000 watt subwoofer; if you are going to play with that much amperage then you've got to have a very, very well thought through power system for the entire vehicle or you will catch something on fire.

 

What I've found over the years is that the fuses never lie - ignore whatever is painted or labeled on the equipment, just look at the fuses and multiply it all out to figure potential power output. Also, the fusing on the amplifier will tell you exactly what kind of primary wiring changes will also have to be made to accomodate it including alternator sizing, big-3 sizing, power run sizing, grounding requirements, etc.

 

Mr. P.

Edited April 25, 2008 by Mr. P. (see edit history)

[Simon]

I toasted one also. I didn't know how but i learned that you need the adaptor that hooks to the bose system in the center console. How did you hook your source signal? If you spliced the wires from a speaker that's prolly the reason.

[faceliftedss]

i have no bose components left in my truck it is all aftermarket.