Amplifier Help

[newUser08]

Hi guys i am experience issues with a subwoofer/amp combo i installed on my 2002 P5. I have an aftermarket HU. I purchased a dual subwoofer/box Model SBX101 with Orion Cobalt 600.2 Amp 2 channel. When I first installed it, it worked fine for 1 month both blowing the fuses on the amp and blowing the subwoofer. The amp is rated 300RMS bridged and the dual sub was 175w rms and 500 peak. (before installing this combo I called Dual and they confirmed it would be fine). I replaced the subwoofer under warranty and 1 month later again same thing happens. At this point I shelled out more money and purchased a pioneer subwoofer rated 250 rms 1100 peak power with the same amp.

After installing the subwoofer and driving to work that day, I smelled a plastic burning smell and the amp blow the fuses again and subwoofer stopped working. I have checked the ground and everything is fine. I dont believe its a short since the amp has been working fine however I have heard that the amp might not be putting out clean power causing the subs to blow. Also heard that there might be some issue internally with the amp but it works fine for a short time.

Can anyone help me out here figure out whats going on. I personally installed this myself and have experience installing systems in my car but I cannot figure out for the life of me whats going on.

 

[MrGiggles]

What impedance is your subwoofer? Most 2 channel amps are only stable at 4 ohms if bridged.

You could be pushing the amp too hard, creating a clipped signal. Turn off all bass boost and set the gain using a DMM. Here is a guide for that.

http://www.glasswolf.net/papers/dmmgain.html

You should also check the voltage at the amp's power terminals. Make sure you are getting enough power there, and it's not dropping below 13 volts or so.

 

[pcb]

Normally,... if an amp is blowing its own fuse, its the amp itself or the dude working the volume control...

 

[newUser08]

What impedance is your subwoofer? Most 2 channel amps are only stable at 4 ohms if bridged.

You could be pushing the amp too hard, creating a clipped signal. Turn off all bass boost and set the gain using a DMM. Here is a guide for that.

http://www.glasswolf.net/papers/dmmgain.html


the subwoofer is 4 ohm so is the amp when bridged. Any suggestions on testing the amp to see if its bad or not?
You should also check the voltage at the amp's power terminals. Make sure you are getting enough power there, and it's not dropping below 13 volts or so.

 

[newUser08]

well the volume was turned up to 20 or so. I would prob say I did have the bass boast up pretty high. Any suggestions on testing the amp and seeing if its bad or not?

 

[MrGiggles]

If the amp plays fine under normal conditions, there's most likely nothing wrong with it. Orion amps used to be top notch, but I'm not sure how they are now.

Bass boost adds a lot of distortion. I smoked a 12" Diamond D3 and a 15" Lanzar with a 1000 watt amp before I figured out it was the remote bass boost knob that was distorting the signal. After I got the subs too hot initially, my amp began to go into protect, and the sub didn't last long after that started happening.

If the power is clipped/distorted, you can smoke a monster sub with a tiny amp.

Sounds like you could use a bigger setup that doesn't need to be pushed as hard.

 

[newUser08]

If the amp plays fine under normal conditions, there's most likely nothing wrong with it. Orion amps used to be top notch, but I'm not sure how they are now.

Bass boost adds a lot of distortion. I smoked a 12" Diamond D3 and a 15" Lanzar with a 1000 watt amp before I figured out it was the remote bass boost knob that was distorting the signal. After I got the subs too hot initially, my amp began to go into protect, and the sub didn't last long after that started happening.

If the power is clipped/distorted, you can smoke a monster sub with a tiny amp.

Sounds like you could use a bigger setup that doesn't need to be pushed as hard.

I too think that the amp is turned up way to high based on my research because based on your statement the amp always powers up and plays fine until it heats up the sub and poof both go down. ANY SUGGESTION on testing the amp to make sure its good with a meter or something before I shell out more money to replace both sub/amp.

When i ordered the subwoofer, crutch field said it would be able to handle my amp with no issues whats so ever.

 

[pcb]

.... ANY SUGGESTION ...

Replace the amp and sub if you can then put in a smaller fuse...

 

[newUser08]

i prefer to have the amp tested before I just replace it. Any ideas on how to do so?

 

[MrGiggles]

I too think that the amp is turned up way to high based on my research because based on your statement the amp always powers up and plays fine until it heats up the sub and poof both go down. ANY SUGGESTION on testing the amp to make sure its good with a meter or something before I shell out more money to replace both sub/amp.

When i ordered the subwoofer, crutch field said it would be able to handle my amp with no issues whats so ever.

There really is no way to test an amp. They work or they don't. The few times I've had a problem, they just went into protect mode after being switched on.

The sub and amp are a good match, I just think you're expecting too much out of them.

Like I mentioned in my first post, I would do a voltage check at the amp to make sure that there isn't resistance somewhere that's causing voltage drop. When voltage drops, amperage increases proportionally, which can blow fuses and melt wires.

 

[newUser08]

There really is no way to test an amp. They work or they don't. The few times I've had a problem, they just went into protect mode after being switched on.

The sub and amp are a good match, I just think you're expecting too much out of them.

Like I mentioned in my first post, I would do a voltage check at the amp to make sure that there isn't resistance somewhere that's causing voltage drop. When voltage drops, amperage increases proportionally, which can blow fuses and melt wires.

thanks for the help. awaiting my infuse fuse to come in and replace it before I start messing with everything again. I hope its me just expecting too much from this set up as you mentioned before.

 

[newUser08]

There really is no way to test an amp. They work or they don't. The few times I've had a problem, they just went into protect mode after being switched on.

The sub and amp are a good match, I just think you're expecting too much out of them.

Like I mentioned in my first post, I would do a voltage check at the amp to make sure that there isn't resistance somewhere that's causing voltage drop. When voltage drops, amperage increases proportionally, which can blow fuses and melt wires.

I replaced my linefuse and everything powered back up. The subwoofer is def blown. I am starting to believe more and more I had the settings set way to high. I plan on testing the voltage to see if that might be the issue as well.

 

[Natey]

I had an Infinity Basslink in the back of my P5 for years and loved it. It didn't bump the neighborhood, but it sounded killer. It's more expensive, but it's already powered and definitely a step up from the Dual sub you had in there.
http://www.crutchfield.com/p_108BASSLIN/Infinity-BassLink.html?tp=114

If you decide to just get another sub that's not self-powered, I'd spend a few bucks and get something that can handle the Orion amp. JL and Boston Acoustics are two good brands to start with.

 

[pcb]

...make sure that there isn't resistance somewhere that's causing voltage drop. ...

You could run a Positive and Negative high power wire right from the battery to the amp... Lowest possible resistance...

Put a fuse on the Positive wire right near the battery...

Remember,... you can only draw 77 Amps before you start drawing from the battery... (no headlights, blower, defog, wipers,.. nothin,.. just the Big Bang effect...)

 

[pcb]

Welding wire makes a great low cost, high current, low resistance, melt resistant, flexible alternative for the expensive stereo stuff.

You can buy it by the foot at some places...

(cannibalizing a set of jumper cables works good too...)

 

[newUser08]

quick update! installed new subwoofer (sony brand that handles 300rms) and lowered the settings. So far so good. Im starting to think that i Had the settings too high!