Problem with brand new Amp

[RobertB]

Hi,
I purchased a basic amp + sub yesterday (In Phase IPX 900 Amp, with a Pioneer TS-W309D4). It has been working great for the past 24 hours. However, I just went to drive to the local supermarket, and my amp has no light on at all!

I've checked both fuses, and the connection at the battery end and amp end. Does anyone have any other ideas? Would this happen if the grounding wire had moved?

Rob

 

[Dr HMS Derv Destroyer]

A break in the ground or remote wire will make it dead. Going on past experience with a mates amp/sub

 

[RobertB]

I'll go check the ground wire now. Would it be safer to disconnect the battery first?

 

[Typhoon]

I'll go check the ground wire now. Would it be safer to disconnect the battery first?

Of course it would.

 

[ThomasBrentnall]

Loop the 12v+ into the rem. If the light comes on your remote wire is faulty!

 

[RobertB]

Thanks Tom, I'm going out to my car to check it out soon.

 

[ThomasBrentnall]

Thanks Tom, I'm going out to my car to check it out soon.

No problem, let me know how you get on

 

[RobertB]

Well I've drilled myself a proper grounding point in the boot floor, so it definately isn't the ground cable messing it up! I'm going to check the rem cable tomorrow, will let you know.

 

[ThomasBrentnall]

Well I've drilled myself a proper grounding point in the boot floor, so it definately isn't the ground cable messing it up! I'm going to check the rem cable tomorrow, will let you know.

Mine is grounded to the screw that holds the rear light(s) in! Sounds like remote

 

[RobertB]

If it is the Rem cable, other than being loose at the back of the HU, what else could be causing an issue?

 

[James28]

Have you got a multimeter?
Red prong on the +ve, black on the -ve. Should read 12v
Red prong on the Remote, black on the -ve. Should read 12v.

If you're not getting 12v from either, it'll be earth. Try putting Red prong on +ve and/or Remote, and the black prong on a bit of bare metal in the car. If it wasn't showing 12v when touching the -ve but is now reading 12v when touching a bare metal part you know its the earth.

If you're not getting 12v when touching the red prong against the +ve and either the -ve or bare metal point, you've got no +ve feed
If you're not getting 12v when touching the red prong against the Remote and either the -ve or bare metal point, you've got no remote feed

Or as someone said, to test the remote wire, you can use a small piece wire, and just bridge the +ve and remote terminals on the amp. If it turns on it'll be your remote.

Hopefully that makes sense.

 

[RobertB]

I don't have a multimeter, but I'll do that test tomorrow. Thanks

 

[James28]

Just leave all the wires plugged into the amp as usual, but bridge the +ve and remote terminals with a spare bit of wire. If it powers on, you're remote wire has an issue somewhere.

You can get multimeters cheap on Amazon for like £3/4. Search on HUKD. I've got one and come in useful so many times.

 

[RobertB]

Well it is now fixed! It was the remote lead, one of my mates crimped it at the back of the HU, and did a f**king awful job. I've tidied it up and it is working great!

 

[James28]

Good stuff.

 

[RobertB]

I am concerned that my amp isn't set up properly though, is there anywhere you know I could take it to get it professionally done? The Car Audio Centre in Leicester wants to charge me £70 to do it.

 

[ThomasBrentnall]

Well it is now fixed! It was the remote lead, one of my mates crimped it at the back of the HU, and did a f**king awful job. I've tidied it up and it is working great!

I guessed correctly right from the start

I am concerned that my amp isn't set up properly though, is there anywhere you know I could take it to get it professionally done? The Car Audio Centre in Leicester wants to charge me £70 to do it.

Is it an active sub / amp or passive?

 

[RobertB]

I think its active. I've got an In-Phase IPX900 2-channel amplifier (http://www.caraudiocentre.co.uk/product_m-in-phase-ipx900_p-23988.htm). I'm bridging both channels to my Pioneer TS-W309D4 12" sub.

 

[ThomasBrentnall]

Well it is now fixed! It was the remote lead, one of my mates crimped it at the back of the HU, and did a f**king awful job. I've tidied it up and it is working great!

I think its active. I've got an In-Phase IPX900 2-channel amplifier (http://www.caraudiocentre.co.uk/product_m-in-phase-ipx900_p-23988.htm). I'm bridging both channels to my Pioneer TS-W309D4 12" sub.

It's passive then. Active = Amp+Sub all combined, passive = separate sub + amp

Read this (copied and pasted as I'm in a rush)!

(Ignore the hot glue bit)

Gains and Volume - When setting gains, do not turn up the amplifier all the way. The gain know is there to match the output of the head unit to the sensitivity needs of the amp. Set the radio to 3/4 volume, and gradually increase the amplifier gain until distortion is noted. Turn the gain down slightly after this. This gives your system additional headroom, and prevents system strain. This issue, if abused, is so important that many pro shops apply a small amount of hot glue to the gain adjustment to indicate when it's been tampered with.

LEVEL is your gain control. This should be calibrated for the approximate maximum amplitude you expect your line level device to provide. For example, if your head unit delivers 500mV max, you should tune your LEVEL/gain control to an input of 500mV. Going below 500mV will appear to make things louder but at the expense of increased clipping (which not only sounds bad but can damage your speakers).

The subsonic filter allows you to set the point at which the amplifier cuts off signals at the low-end of the spectrum. Since < 15Hz signals aren't doing anything for your ears anyway but do cause excursion (and potentially damage), you should set your subsonic filter around there. Somewhere around 15-20Hz is fine. It's not a hard cut-off, so being precise isn't important on this one.

Your low pass filter is the point above which your amplifier doesn't amplify, frequency-wise. Setting this around 80Hz on a proper system is appropriate. If you don't have dedicated mid-bass then you may want to set it higher, but do not set it in excess of ~120Hz unless you want crappy, muddy bass. The higher this is set, the wider the frequency range your amplifier (and thus sub) will attempt to reproduce. Take note that the higher the frequency you set the crappier your bass will sound though louder.

Boost should be disabled on a proper system. If you don't have enough bass, you need more honest power. If you want to purposely distort your music in the interests of bass, increase it to where you're comfortable. Take note that this can cause clipping even if your gain is set properly due to the nature of the beast. You can damage your speakers if you aren't careful.

 

[RobertB]

Thanks mate, I'll go do it in a while!