Car Audio Help (

[Scotty1981]

My old RCA cables that connect the headunit(HU) and Amplifier went bad inside the cover a small break, they only worked in certain position.

These were part of a decent Rockford Fosgate amp installation kit. I bought a pair of Schoshe RCA cables from the car audio section of WalMart.

Now I get a strange very faint hum from my subs when no music is being played.

Some major distortion on heavier base.

Some popping when turning on and off the HU but not when turning on/off the source of the music plugged into the aux input. No popping when turning on or off the car only the headunit.

I just ordered some Rockford Fosgate RFIT RCA cables do you think this would fix it? Or is the problem in the amp possibly?

I do have the signal and power cables ran on the same side of the car but this was never a problem before.

If anyone can help I would appreciate it, if you are Columbus, OH maybe you can take a look in person as well. Just let me know.

 

[Jimmy9190]

The hum in the subs when nothing is playing can be from routing the new RCA's too close to an electrical source such as a fan motor, body control module or electrical control unit in the vehicle. It can also come from routing the RCA's too close to an existing wire harness in the vehicle. These types of noise are called radiated noise, and usually (but not always) a good set of shielded RCA's will reject radiated noise. As a test you can just run the ground wire through the interior of the vehicle down the center to see if the hum goes away.

You can try connecting a ground wire from the ground on the amplifier to the ground wire on the radio. 16-18 gauge will be fine. It's always best to ground the radio and amplifier at the same point, it will eliminate the chance for ground loops which is a big cause of system and engine noise in car audio. If that doesn't help, try connecting a short piece of wire from chassis ground at the amp to the shield on the RCA's.

The popping in the amp can be indicative of a power supply in the amp that is beginning to have problems. You can try to eliminate the pop noise by wiring in a plain 30 amp Bosch relay:

Terminal 86 to your remote on wire from the radio
Terminal 85 to ground
Terminal 87 to 12 volts positive
Terminal 30 to the remote on wire of your amp
No connection on terminal 87a

The hum in the bass can be a sign the amp is starting to have internal problems. The distortion in the bass can also be an indication you are beginning to have problems with the amplifier. So can the fact that the RCA connections are having problems. The RCA's probably are not the cause of any of the problems you are having with your system. You may need to either get a new amp, or get your amp repaired if you want to keep it.

 

[Scotty1981]

That's what I was afraid of, someone who seemed to know about car audio I spoke with reccomended I try the same brand RCAs I had before so I ordered a set of Rockford Fosgate RFIT now it seems like I wasted 24 bucks if it is the amplifier going bad, it is pretty old so that may be it. If it is interference from the power wire then hopefully the new wire will fix it.

I was hoping the new wire would work since it sounded ok before I replaced it. Maybe I messed up the RCA connections on the amp when I was playing the wire trying to get it to a position where it would work before I figured out the wire was broken inside of the insulation.

I am not sure what you mean by the Terminal stuff.

The amplifier and subs and box came as a set back when fast and the furious came out, it is a lightning audio fast and furious kit I got at best buy. Im not sure what the amp is rated but I think it is either 150 or 300 watt, I think 150 though. Can you reccomend a good amplifier? I don't want something super cheap but I dont want to buy more than I need. I'm not looking for window rattling bass, just something that sounds better than most factory radios.

Are there any good chain audio shops that I can take it to and have it checked out or should I stay away from audio places? I've heard a lot of horror stories.

 

[Jimmy9190]

Lightning Audio is pretty cheaply made. IIRC The Fast and Furious came out about 5 years ago. If you got 5 years out of a Lightning Audio amp you got your money's worth from it. Depending on what you did when playing around with your RCA connections, you could very well have damaged the RCA istelf, the circuit board or the solder joints inside the amplifier.

As far as replacement amplifiers go all I can say is try to buy the best amp you can for the money you have to spend. Don't spend more than you can afford. Car audio gear is a lot less expensive now than it was back when I was an installer 10 years ago. But a lot of it is now made in China or other foreign countries too. It used to be that American-made amps were best for bass because they had the largest and heaviest power supplies which gives more power and volume from the subs. Rockford used to be US made, so did a lot of other good brands. I use a JL Audio 300/4 amp and a single JL 10W0 sub. I really like the JL amplifiers, but that is just one brand that is good. There are several others that are good too. You need to shop around and ask your friends what they have and find out how good it is. And "good" does not necessarily mean "loud". It means the amp is reliable and will last a long time. My JL amp is 5 years old and still sounds as good as the day I got it.

Best Buy is a decent place to shop for an amp. I used to work there a long time ago. But you would likely get better service, better installation and probably a better price at an independent car audio store. Best thing I can tell you about that is shop around, check online reviews or car audio message boards and ask your friends or their friends which shops in your town are good and which ones are not. The better independent shops tend to have a fairly devoted following of repeat customers. Some independent shops will also have in-house repair technicians too who might be able to check your old amp out for you.

 

[JHZR2]

wal mart parts... 'nuff said.

 

[brianl703]

I got a good deal on a 4-channel JVC amp a few years ago. It was a 2005 model and I bought it in 2007, so it was new old stock and was a lot cheaper than current models. Also I've gotten good deals on speakers that were last year's model and on closeout.

Neither speakers nor amplifiers have a lot of innovation from year to year so you aren't loosing anything by buying a discontinued model. Most likely, the new model has some cosmetic changes and that's about it.

 

[Scotty1981]

Ok, I suppose it couldn't hurt to run the Rockford Fosgate RCA wire for better sound anyway and I'll start looking for a new amp. I don't think I would want to spend more than 100 or 120 dollars or so though, I'll go up to the store and price some open box or discontinued models. Thank you for your help.

 

[Summerwind]

Scotty, Alpine also makes a very nice 500watt sub amp. I have one in my GMQ with a type S 12" sub, and have been very happy with it. More power than I will ever sanely use. I also as mentioned went to a private audio dealer.

 

[Scotty1981]

I already have the wire ran so I just have to plug in in basically. I can handle that much. I will look into the Alpine, what model is it?

 

[Summerwind]

Hey Scotty, I dont have access to it at the moment, but I believe it is the M300 or something close to that, She is 300W into 4 ohms, but goes up too 500W at 2 ohm, and on peaks. It seems (to me) to have excellent range and control

 

[Scotty1981]

I found my old amps specs online and it was a 350W amp but I think it was only delivering 350 Peak and probably more like 150 RMS.

 

[Scotty1981]

Im replacing the RCA wire with Rockford Fosgate and dumping the Scosche and we'll see if that gets it back to where I was before with decent sound.

If that doesn't work then I will also try for a new amp.

 

[occupant]

I like the whine in my car's AM radio. It's like a tachometer to me.