Crackle from speakers

[RobWarren]

Situation:

Kenwood CD player was vandalised and broken.
Replacement Pioneer unit is installed but there's a crackle when ignition is on.

From the searches I've done this appears to be coming from outputs at the Dizzy and Alternator, possibly the spark plugs too, thanks to having wires instead of modern carbon connectors.

However, the Kenwood stereo worked just fine. I even intercepted the power lead on the new one and put in the capacitor from the Kenwood (on a mate's advice) but that failed to have any effect.

Is this simply a capacitor issue? I'm no electrician so I'm not entirely sure of the concepts involved here. Would a cpacitor be required at each of the offending units? I don't want to have to change all the wires out unless I have to.

Advice appreciated.

Bob

 

[RonMacPherson]

Okay, see if disconnecting the alternator for a short time while you operate the stereo(usually got more static on am, but that was decades ago). If so you can install a capacitor there. If not, and you suspect ignition, capacitors strenght can be upsized (to go on the coil). Plus make sure you have good ground to the stereo and complete speaker circuits(which should include ground back to the stereo). Try switching positions on offending speakers, + to - temporarily, see if that has any affect.

 

[healeynut]

Radio Shack sells a stereo power lead filter for stereos which seems to really helps with this problem...

 

[GregW]

Hi Bob,
Are the spark plugs you have in now resistor type? If not, that would be the first thing I'd try. FWIW

 

[RobWarren]

Thanks for your ideas guys.

I'm not sure what type of plugs are in . They're new from the recent engine rebuild but I'll check.

The previous Kenwood unit had a power lead filter and I tried putting this in the power line for the Pioneer but it wasn't happy. Perhaps one is required on the alternator and/ or coil as Ron suggested.

It's a little disappointing that the people I know who are professionals in car audio installation have no idea how to fix this problem. Kids today!

Rob

 

[Ed_K]

I had the pops and crackles from my speakers when I had stranded metal ignition wires. I should mention that I am using a 40 kv petronix coil and ignition trigger.
I fixed the noise by replacing those ignition wires with Magnecor ignition wires.
Magnecor makes three different sets to fit our cars. One of those sets are black and the correct diameter to fit in our stock, side entry distributor caps. Another set ( red ) will fit into the top entry replacement distributor caps that are readily available.
Here is a link.
https://www.magnecor.com/
I was impressed with their design and since installing them, I have not had any hint of any kind of noise in my speakers. I also have a small remote sub wuffer and amp and there is no hint of any noise in it either.
If I ever need to replace any ignition wires in any of my daily drivers, I would also use magnecor wires. It is a good design and they use quality materials.
Ed

 

[Ed_K]

I should also mention if your noise is coming from the generator, it would be a " whining or whistling " kind of noise, not pops and crackles. Modern electronic devices generally contain enough filtering in the power regulation/supply to get rid of noise signals of the frequency generated by our generators.
The pops and crackles are from the six 40,000 volt radio transmitting antennas, ( standard construction metal ignition wires ), under the bonnet.

Ed

 

[RobWarren]

Thanks Ed

The noise isn't alternator - no whining involved - it's definitely the coil. I need to get a new lead by the sound of it...the tough part is trying to get it all sorted prior to Christmas as I'm away on 25th taking the car on a tour of NSW national parks and the mountains.

Nothing like a bit of pressure....