Crackling help!!

[Jeffy]

I need some serious help, I've researched for countless hours and I'm about to lose my freaking mind. No matter what I do, I can't get rid of a high frequency crackle/ distortion, and I keep blowing speakers. I bought the car a month ago and entirely replaced the stereo system, including running new wires for the speakers.

I'm running (2) Rockford Fosgate T1692 and (2) Fosgate T1675 from a PDX-V9, and (2) Fosgate T1675 and a JL 12W6 off another PDX-V9. I have a Pumpkin Auto head unit (Chinese knockoff, but sounded amazing for a while- read on). I had (2) JL C2-350x dash speakers running from this head unit. I tuned the amps properly with a multimeter.

I initially installed everything, and after working out the kinks it sounded beautiful. A few days later I was driving on the freeway with the windows down so I cranked it up. Later that night I started noticing issues. I somehow blew the tweeters in the dash speakers, even though they're rated for 75w peak and my head unit is only rated for 50w peak (verified blown with multimeter). Ok, bummer. I ordered a pair of JL C5075-CT tweeters to replace them. However when I got the tweeters and went to install them, they sound horrible at all volumes. The distortion is so bad during vocals that I can't understand the words, and that's with the volume at only 15-25%. I tried connecting them to the amp instead but same result... There's no way 2 brand new speakers from a good company are both bad.

So I ripped out my head unit wiring, re-soldered everything and ran a new ground. No good. ALL of the Rockford Fosgate speakers running from my amps have distortion/ crackling at high frequencies too. I tried isolating speakers, but they all sound bad even when they're the only one connected.

WHAT IS GOING ON???

Click to read more...

 

[Jeffy]

I'm currently tracking down an O-scope to test the head unit. Any other ideas?

 

[Massive spl]

Cheap HU

Blew tweeter and prly fried the HU channel that tweeter was on?

If you can try a different HU... Or maybe you have a speaker wire that got pinched/sliced and is grounding itself out. Just retrace everything

 

[Jeffdachef 5,000+ posts]

junk head unit. Head units only put out 5-10 actual watts per channel. That peak watt sh*t is what they list to fool noobs, utterly garbage number that you should never even consider looking at ever again. You clipped and killed the tweeter with dirty head unit power from a dirty chinese head unit. Dirty - as in poorly made bad circuitry, unclean signal.

 

[Jeffy]

Cheap HUBlew tweeter and prly fried the HU channel that tweeter was on?

That's what I'm starting to think... But would that effect the output to the amps as well? Why would the signal to them still sound bad?

If you can try a different HU... Or maybe you have a speaker wire that got pinched/sliced and is grounding itself out. Just retrace everything

I'm tracking down an o-scope to test the HU and see if that's the issue. I've triple checked all wires and they're good. They're about 3 weeks old and well insulated. I made sure to run them where there's no pinching.

 

[Jeffy]

junk head unit. Head units only put out 5-10 actual watts per channel. That peak watt sh*t is what they list to fool noobs, utterly garbage number that you should never even consider looking at ever again. You clipped and killed the tweeter with dirty head unit power from a dirty chinese head unit. Dirty - as in poorly made bad circuitry, unclean signal.

Yea I figured that was a part of it, but why would the signal to the amps be compromised? And why would brand new tweeters sound bad at all volumes?

 

[Jeffdachef 5,000+ posts]

Yea I figured that was a part of it, but why would the signal to the amps be compromised? And why would brand new tweeters sound bad at all volumes?

of course it affects the output to the amp. A good system starts with a good signal. If the signal from a head unit is weak and you force it to put out a strong signal, you get a dirty signal. Head unit pre-outs can easily clip and destroy your equipment if you have a head unit making a dirty signal. Dont think a head unit is just a head unit, theres a reason why serious audio guys buy proper head units with powerful internal circuitry and 24 bit DACs with high pre-out voltage.

 

[Jeffy]

of course it affects the output to the amp. A good system starts with a good signal. If the signal from a head unit is weak and you force it to put out a strong signal, you get a dirty signal. Head unit pre-outs can easily clip and destroy your equipment if you have a head unit making a dirty signal. Dont think a head unit is just a head unit, theres a reason why serious audio guys buy proper head units with powerful internal circuitry and 24 bit DACs with high pre-out voltage.

Ok thanks, I'm not exactly an expert on all this. If what you say is what's happening in my system, an o-scope will identify this pretty quickly, correct?

 

[Jeffdachef 5,000+ posts]

Ok thanks, I'm not exactly an expert on all this. If what you say is what's happening in my system, an o-scope will identify this pretty quickly, correct?

pretty much.

 

[Jeffy]

pretty much.

Ok well that's easy enough. Am I doing anything wrong with the rest of my system? Is that a good combo for the amps/ speakers?

After I get a new HU I'll just run the new dash speakers from the PDX amp to make it nicer

 

[Jeffdachef 5,000+ posts]

Ok well that's easy enough. Am I doing anything wrong with the rest of my system? Is that a good combo for the amps/ speakers?After I get a new HU I'll just run the new dash speakers from the PDX amp to make it nicer

to be honest man get a dedicated midrange for the dash, run your whole system active and get a digital sound processor or a 4 way active capable head unit if you want your setup to sound majestic. If you think it currently sounds beautiful now, wait till you get it properly EQ'd and time aligned and crossed over properly. You'll never ever want to leave your car.

 

[audiobaun 5,000+ posts]

Really enjoy my old Eclipse CD3000..Its hard to place a newer HU in its place..If you dont have funds for a Pioneer PRS80,or spmething within that catagory/specs, Kenwood 4v HUs are pretty decent for the money.For really nice voltage HUs, some older Eclipse HUs are put out a really clean higher voltage signal,yet, may lack some new capabilities/functions

 

[Jeffy]

to be honest man get a dedicated midrange for the dash, run your whole system active and get a digital sound processor or a 4 way active capable head unit if you want your setup to sound majestic. If you think it currently sounds beautiful now, wait till you get it properly EQ'd and time aligned and crossed over properly. You'll never ever want to leave your car.

Well the dash speakers are only 3.5", and I don't want to start cutting to fit a good midrange in there. I did that on my last car and never liked how it came out (didn't look good). I was really happy with how it sounded right before these issues, I'd be perfectly happy bringing it back to that level. Adding active crossovers and all that is more money and time than I want to spend, I don't need perfect reproduction. What I had going was already far above antibody else I know, and it's plenty for my usage

Thanks for your help, I'll test with an oscope, and hopefully that's the last of my issues

 

[Jeffy]

Really enjoy my old Eclipse CD3000..Its hard to place a newer HU in its place..If you dont have funds for a Pioneer PRS80,or spmething within that catagory/specs, Kenwood 4v HUs are pretty decent for the money.For really nice voltage HUs, some older Eclipse HUs are put out a really clean higher voltage signal,yet, may lack some new capabilities/functions

I'll check those out. I really liked the features this head unit had, I'll be sorry to see it go. It was basically a full Android tablet built into a double din enclosure, it even did WiFi pairing with my phone's internet.

 

[Jeffdachef 5,000+ posts]

there are 3 inch to 3.5 inch midranges. Not like you need to fit a 4 incher in there. Never even said anything about cutting. A ppi 88r dsp or soundstream harmony runs you 200 dollars and you get 8 channels of clean output, 31 bands of Eq, 32 bit processor, bandpass crossovers with adjustable slopes and time alignment.