Audio Help!

-westy- · 11 Jul 2007 at 01:10

I'm currently experiencing a problem with the audio in my car. I have an amp and sub fitted, however the sub is disconnected, the amp is running just the 2 front speakers.

Basically, whenever I turn the headunit up too much, the music cuts, then comes back for a second, then cuts (and repeat)

I'm tried turning down the input sensitivity on the amplifier, to no avail

Any ideas?

Thanks

Jonny ///M · 11 Jul 2007 at 01:13

Where have you grounded your amp to? Sounds as if it has a bad ground so is cutting on and off.

digitalwolf · 11 Jul 2007 at 01:19

It's a power issue.

My amp running my sub used to do it. I was told I needed a big capacitor.

-westy- · 11 Jul 2007 at 01:27

Jonny ///M said:
Where have you grounded your amp to? Sounds as if it has a bad ground so is cutting on and off.

The amp is grounded to a bolt in the boot, perfectly secure. I'll check the connections tomorrow. Its strange that it only happens when I turn the volume up though?

digitalwolf - a bigger capacitor? wha?

digitalwolf · 11 Jul 2007 at 01:30

I'm not sure what they are. They are big cylinder like objects with digital displays on that most boy racers have on their systems (high watt systems) to regulate the power.

Pretty sure they are capacitors, don't count me on it though.

-westy- · 11 Jul 2007 at 01:32

well the headunit is only supplying about 50w to the amp, and the amp is only about 400w maximum, so I don't think its big power!

digitalwolf · 11 Jul 2007 at 01:34

What is on the end of the amp? A sub?

Six6siX · 11 Jul 2007 at 01:35

Capacitors buffer the power - they store energy so that when you get deep bass from a sub for example, it draws more current hence the cap is needed to provide the extra power.

IMO its not really necessary in all but the most high powered systems. If used for the wrong reasons it more often than not causes more problems that it's worth (more strain on battery and alternator).

Sounds like a grounding issue to me, check and double check power connectors and that you don't have a short between wires at terminals anywhere. Does the amplifier have a warning/diagonistic light on it?

-westy- · 11 Jul 2007 at 01:37

digitalwolf said:
What is on the end of the amp? A sub?

It goes:

HU ---> Amp ---> Sub
---> Front speakers

The sub is currently disconnected, so the amp is purely driving the front speakers.

digitalwolf · 11 Jul 2007 at 01:40

Six6siX said:
Capacitors buffer the power - they store energy so that when you get deep bass from a sub for example, it draws more current hence the cap is needed to provide the extra power.

IMO its not really necessary in all but the most high powered systems. If used for the wrong reasons it more often than not causes more problems that it's worth (more strain on battery and alternator).

Sounds like a grounding issue to me, check and double check power connectors and that you don't have a short between wires at terminals anywhere. Does the amplifier have a warning/diagonistic light on it?

I had no idea westy was using a lowish powered system. I know my mate running 2 x 750w subs had this problem and the capacitor cured them.

My sub drops out when my HU is turned up and the amp is drawing too much power. It's not an ground/earth issue, it's that the altenator cannot supply enough current to the amp and the rest of the car electrics at the same time so it drops out.

Six6siX · 11 Jul 2007 at 01:47

digitalwolf said:
I had no idea westy was using a lowish powered system. I know my mate running 2 x 750w subs had this problem and the capacitor cured them.

Yup thats when it would be a good idea: the amp needs the power which it can't get without using the capacitor store. I just meant that they have their uses.

digitalwolf said:
My sub drops out when my HU is turned up and the amp is drawing too much power. It's not an ground/earth issue, it's that the altenator cannot supply enough current to the amp and the rest of the car electrics at the same time so it drops out.

Strange, I ran 600W+ systems from a weedy Punto 55 and had none of these issues. What gauge wiring you using? Does the amp go into protection mode or does it just cut out?

digitalwolf · 11 Jul 2007 at 01:51

Six6siX said:
Yup thats when it would be a good idea: the amp needs the power which it can't get without using the capacitor store. I just meant that they have their uses.

Strange, I ran 600W+ systems from a weedy Punto 55 and had none of these issues. What gauge wiring you using? Does the amp go into protection mode or does it just cut out?

The cable is pretty thick stuff. The RMS of the sub is 300w and my amp bridged is pumping out 290w rms.

I have a feeling when the sub puts the amp under some heavy strain it just bails out.

Doesn't go into protect mode no. The HU used to drop out (lights on it etc) before I altered the output power/bass boost on the amp.

Six6siX · 11 Jul 2007 at 01:58

digitalwolf said:
The cable is pretty thick stuff. The RMS of the sub is 300w and my amp bridged is pumping out 290w rms.

I have a feeling when the sub puts the amp under some heavy strain it just bails out.

lol loud music much

digitalwolf said:
Doesn't go into protect mode no. The HU used to drop out (lights on it etc) before I altered the output power/bass boost on the amp.

What is the 300rms rating at 2ohms stable or 4ohms? I came across some issues when connecting a DVC sub in 2ohm mode, for example, across bridged terminals which are expecting a 4ohm load. The lower load resistance would give you higher current draw. I'd expect something like that to trip a protection circuit though...

Upgrade your alternator tbh

(jk)

digitalwolf · 11 Jul 2007 at 01:59

Six6siX said:
lol loud music much

What is the 300rms rating at 2ohms stable or 4ohms? I came across some issues when connecting a DVC sub in 2ohm mode, for example, across bridged terminals which are expecting a 4ohm load. The lower load resistance would give you higher current draw. I'd expect something like that to trip a protection circuit though...

Upgrade your alternator tbh (jk)

Well I upped the battery to a decent one lol.

I'm pretty sure it's 2 ohms.

-westy- · 11 Jul 2007 at 12:33

All sorted now!

The connections for the sub (which I had stupidly left loose..) were shorting - I took them off, now it works fine!

Lucky I didn't fry the amp I suppose!

Thanks