Tuning a stereo system

[pityocamptes]

Hopefully I can get the @$@#@# whine noise taken care of this weekend. Assuming I do, what is the best way to adjust the amps, HU to get the best sound out of the components? Thanks!

[zigzagflux]

Perhaps, for the sake of the new thread, you could summarize your system topology?

Head unit, processors, crossover types and adjustability, speakers, amplifiers..............

[pityocamptes]

Its a jensen HU with preamp outs, one pyramid 300 watt amp for tweets and mids (pyramid bullet tweet, and power acoustic mids), and lanzar 1200 watt amp with 2 - 12" visoniks.

[grjr]

First check your wiring is solid, power and signal lines. Check that you have good grounds for your headunit and amplifiers, check the grounds under the hood as well. I also am suspect of the headunit, maybe try adding a power line filter before the headunit.

[zigzagflux]

Passive crossover for the front speakers? Is there any adjustability you have (i.e. are you biamping).

[Clipped]

reground everything properly...

and add a ground wire to the chassis of the cd player and ground it also...

if your using rca jacks with metal heads they may be picking up noise....or if you are using rca jacks with REALLY thin insulation get rid of them for something with a bit thicker insulation.

turning down the gain will also help alleviate some of the noise.

[pityocamptes]

Check my other post on grounding. Thoughts?

I do have RCA jacks with metal heads, do they make something else? The insulation is very thick on the wires. I tried grouding the HU chassis and it made no difference.

[ppia600]

There is nothing wrong with the barrels of the rcas being metal. It is actually better, it keeps them shielded all of the way from end to end.

[Clipped]

sorry, id have to disagree with you on this PPI...

for the rca jacks with metal heads (not metal looking plastic )with screw on barrels, will act like one big RF antennae.

you basically have an exposed ground on the rca line, anything that touches it can induce noise, any radiating noise travelling through the chassis can be picked up by the metal head if close enough.

usually there is a tube of clear plastic that goes over the internals before screwing them together, to prvent the ground touching the metal head...many times this plastic tube is discarded when assembled....or moves

the ones with metal heads are also notorious for broken ground terminals inside....metal headed jacks are not designed for car use and are not as immune to vibration as regular plastic heads which are molded and secures the wire's solder points.

just for clarification im not talking about the actual wire , im talking about the actual jack head.

[ppia600]

I am talking about the jack head as well. The point of having the metal head is to keep the ground path complete from end to end. You can use the plastic molded type which are easier to manufacture with automated equipment, but the ground shield will stop a few millimeters short of the actual outer terminal and the center lead is exposed (like an antenna) The only way a metal jack will cause a problem is if it is too long and causes fit issues, or if you are irresponsible and don't insulate all of your positive voltage wires. There shouldn't be any bare wires floating around behind your radio either way. If there are, you have more important issues to deal with rather than worrying about the differences between molded and metal rca ends. If you are that worried that you can't keep your other wires from touching the rca barrels.. wrap some tape around them. Either way, the barrels are at the same ground level as the deck 99% of the time so what is the point?