My best friend just got a system! I'm so excited!

[Justinw303 10+ year member]

He's the second person in our group of friends to get a system installed. The first guy has 2 10" P2's from RF on a P3001 amp, I believe. I'm pretty sure he has it wired incorrectly because he says it's bridged, but the subs are SVC 4-ohm so he's either running 2 ohms or 8 ohms, either way that's bad for his setup.

But forget him. My friend has 2 Infinity Perfect 12.1d's hooked up to an Infinity Reference 1211a amp, getting around 427 watts to each sub. The RMS is 350, but from what I've heard they're a little overrated, and even if they weren't, 75 watts over won't kill it, I suppose.

Anyway, I was listening to them in his truck yesterday and they got pretty loud on the inside, but I don't know if it has some sound deadening in from the last guy who owned it, or if it was made like this (It's a ninty-something Tahoe), but when the sub is pounding on the inside, if you step out and listen from about 3 feet away from the side of it, you can barely hear the bass. I'm not saying this is a bad thing, but it's a little wierd.

But I am worried about him blowing the subs though, because the gains aren't even close being set properly. The guy who hooked it up did a great job(I checked all the wiring and it looked good), but I really don't think the gains are set right.

For one, he still has the stock radio, and if you know anything about Chevy, you know they like having a rotary knob with no volume level indicators at all, which I hate. So, this means he can't possibly know when he's started clipping because He doesn't have a set volume not to go over. I told him he needed a new CD player, but he prefers the stock look. Oh well, I won't stop until he fixes it.

Lastly, I know there is a slight problem with his box, but I'm not exactly sure what it is. When he turns it up, it sounds like there's a rattle from the left sub. I started looking around the edge of the woofer and noticed a 2 square inch piece of the carpet that was vibrating really bad on the edge of the left woofer. Now, I think that means there is something wrong with the wood under it, but I'm not sure what. Can anyone help me here?

And thanks for reading. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

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[jacko 10+ year member]

How do you know the gains are set improperly? How was the carpet vibrating? like moving in and out against the wood?

 

[btnhfan 5,000+ posts]

Actually it might kill those subs

The infinty rms rating is also their thermal rating......

 

[Justinw303 10+ year member]

How do you know the gains are set improperly? How was the carpet vibrating? like moving in and out against the wood?

Because for one, even if they were set properly, he wouldn't know when he was exceeding those limits because of his stupid radio. And secondly, he has some remote knob that is wired to the front of it, and I'm pretty sure it's a remote gain adjuster, and he's messed with it a couple times already so it can't be set right now...

And it's more like a blurry vibration. Like when the bass hits the carpet vibrates really dast and gets blurry, but the rest of the carpet stays still. It might be moving against the wood, but the rattle was still there when I tried to press it down.

I'm thinking maybe a weak piece of wood, that might be resonating in that spot. But I'm no expert.

 

[Justinw303 10+ year member]

Actually it might kill those subs
The infinty rms rating is also their thermal rating......

thermal rating is... sorry, I'm still learning a little myself. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

And the max wattage rating for the subs is 1600, I believe, and I know that doesn't mean jack, but with a max that high, you wouldn't think 75 watts over would kill them.

 

[Moe Lester 10+ year member]

thermal rating is... sorry, I'm still learning a little myself. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
And the max wattage rating for the subs is 1600, I believe, and I know that doesn't mean jack, but with a max that high, you wouldn't think 75 watts over would kill them.

thermal rating = how much heat the coil can dissipate without blowing. the infinities dont like very much over their rms at all.

 

[jacko 10+ year member]

The knob is bass boost adjuster. Just set this to 0 to set the gains. I have no clue what your talking about, most other radios don't have a little "clipping" indicator for the deck. Is it just speaker level inputs on the amplifier or is he using a line driver? More information is needed to have a general idea of what the gains should be at without actually just setting them by ear.

Edit: Ic ic about the volume indicator, like I know that I have the gains set on my amp where the amps will start clipping at 47/62. Gotcha, Just train your friends ear to listen for distortion. Are the subs in a ported or sealed box?

 

[btnhfan 5,000+ posts]

But you most likely arent getting 427w at all

You might be okay

If the subs fry, then youll know why

 

[Justinw303 10+ year member]

But you most likely arent getting 427w at all

Why not? And the subs are in a sealed, 2 chamber box.

 

[Justintoxicated 10+ year member]

sounds like the box has an airleak, sounds like he is using the LOC form the stock HU, whih could be sending a VERY poor signal to the amp (don't know this for sure but most stock HU's don't have pre-outs) I know on my Truck an LOC is a huge NONO. Volume controll thing being a knob isn't so much an issue IMO, but if it's a stock HU it probably does not have much power which will distort speakers.

 

[btnhfan 5,000+ posts]

Theres so many factors as to why you are not

You are probably not holding a constant 14.4v the whole time

Box rise

Put a dmm on the coils and see what they actually measure.

It maybe like 4.5 or something like that

etc..

 

[theCybe 5,000+ posts]

* impedance rise

 

[AVSTANG02]

You guys are talkin shit.

Infnitys can take a beating. At one point I was over powering the reference series each by 100watts. Gains set with DMM....

To the thread starter: You should be shot you are a member of this forum and you go ahead and let your friends get that equipment for there systems?

 

[Tirefryr 10+ year member]

Holy crap!

Guys we really need to understand here that without the proper testing equipment, the actual power output can be at best, just an estimate. Take it however you will, but there are so many variable that are constantly changing. Power output will change as well, as will power handling.

 

[theCybe 5,000+ posts]

You fucking twits. //content.invisioncic.com/y282845/emoticons/mad.gif.c18f003ab0ef8a0d9c27ca78d77a6392.gif

Here's an example.

"You're wondering how their store can sell your items there. They're on sale."

You're undereducated. ( You+are undereducated. )

Your education suffers. ( The education belongs to you. It is yours. )

There's a problem with that. ( There+is a problem. The problem is there. )

It's their problem. ( It's a problem that belongs to them. )

They're not doing anything about it. ( They+are who is not learning. )

Things to sell are on sale.

//content.invisioncic.com/y282845/emoticons/furious.gif.fc81ca146dbff91fede3ed290dbc4f4c.gif Is that too god*amned fancy to understand?

I hate you.

Love,

Cybe.