Rep Power: 0

I'm getting INTERFERENCE NOISE UP THE FREAKING *** with my MTX 6304. Its placed under the passenger seat. So i guess im going to try to move it to the trunk. It not only makes a whine w/ the engine, but also *pop*, pause, *pop*, pause *pop*, and so on. Whats that??? The *pop* noise goes away when i unplug one set of RCAs, but the whine still persists, but not loud at all, but still I want to achive absolute silence. So you guys think the best thing to do is relocate to the seat-back?

 
Rep Power: 329

If the popping is coming from the RCA's try routing them elsewhere. They could be catching interference from power wires behind the HU, or the ignition wire under the steering column. It doesnt sound like a problem from power wire though, so I would also check the insulation on them; they could have gotten pierced somewhere and are contacting metal. If all else fails, replace them.

As far as the alternater whine, re-ground, and check to make sure your speaker wire isnt coming into contact with ANY power wire.

 
Rep Power: 0

Thanks man... the weird thing is, the MTX amp has the power and speaker outputs on the same side...do speaker output wires matter too if they cross power lines? Cuz mine do. I'll have to RE route them around the amp i guess. And as far as the RCA goes, i actually PULLED them out completely (while plugged in) and waved them around the interior of the car, and the noise does go away as i hold the RCAs near the roof, but then I still get a whine. Put the wires low, and i get a POP pop... im using a schoshe wire kit, including 1 schoshe (cant spell it) RCA, and one Rockford RCA. If all else fails, I'll just re do the amp in the trunk, will 8 gauge wire be fine? Im using 4 gauge right now, it seems way too thick.

 
Rep Power: 329

yup, speaker outputs crossing a powerwire are most likely the cause of your alternator whine problem. You could be getting RCA interference from the SRS harnesses under your seats as well....try to keep them away from all power wire/OEM harnesses. And as far as power wire....look in the manual and see what it recomends. If the amp can fit a 4 AUG wire then its not too much.

 
Rep Power: 812

Make sure you have a good ground attached tightly to BARE metal. Also, you should get some low noise RCA monster cable.

 
Rep Power: 0

UPDATE GUYS: Heres what happens. If I have two sets of RCA cables plugged in simultaneously (front and rear speakers), i get a popping noise, if i unplug EITHER SET (either front or rear rcas), the noise goes away. So I can only have one set of rcas plugged in and NO noise, but if i plug in both, i get noise. What does this mean?

PS- I didnt cut the speaker wires that come directly from the HU harness (ran previously w/o an amp), would this cause noise? I dont see how it coud since they arent plugged into anything haha

 
Rep Power: 0

And my ground is attached to metal that is as shaved as can be. Grinded it down with a grinder attachment @ 35,000 RPM hahaha

 
Rep Power: 0

Oh, and today yes I ran my speaker output wires away from the power cables ... still noise :-/ The polk momos sound freaking CLEAR and crisp though. Though somewhat bright hahaha

Mariah Carey's voice sounds so crystal clear, ear shattering lol.

 
Rep Power: 329

I have a thought....I just looked at the manual for your amp, and there is a button switch that allows the amp to use 4 channel inputs or 2 channel inputs (1 set of RCA's vr. 2 sets and sending signal from that 1 set to both output channels)

Since you have two RCA's plugged in, and the noise goes away when you remove one set, perhaps the button is in the 2 channel position? You might want to check that out and make sure it's in the 4 channel position.

As far as the whine, you could also be getting it from having RCA's by a power cable, so if your RCA's are crossing power anyplace, fix that, and double check your speaker wiring.

 
Rep Power: 0

I'll do that right now! I really appreciate your help man. Thanks al ot!. Ill be back later with the results.

 
Rep Power: 329

No problem....let me know how it turns out.

 
Rep Power: 0

K, tried it. Same result. I thought of one last thing... my HU is grounded using the stock harness (Alpine cda 9807), should i ground it to the chassis? I think the reason why i hear the noise now (vs before w/o the amp) is cause the NOISE was always there, but now the amp is just bringing (amplifying) the noise out. Should this be a concern?

 
Rep Power: 347

I had this problem for a long time and I tried everything. I was also using an MTX amp too...with Monster XLN 201 RCAs. This is what I had to do to get rid of it: move the wires behind the head unit around. Move them so they are close to the back of the HU and far to the right. I bet people with Pioneers don't have this problem because I think that you plug Pioneers directly into the back of the HU...but with a Kenwood with long RCA connections, the wiring falls towards the back where there is a lot of electric looking things

 
Rep Power: 812

I have a pioneer and it has long cables for the rca's, too. I never had a problem.

 
Rep Power: 330

i had a pioneer... and i had problems. the front RCA's had fairly long cables on my pioneer though, as does my kenwood. try maybe cramming the RCA's above the air ducts behind your head unit, or maybe taping them somehow onto the bottom of the ducts.

also, does that amp have pre-amp outputs? maybe run one cable to the amp and then one off of the pre amp outputs, see if that does anything.

 
Rep Power: 0

Im looking for clean sound, so rcas is a must. I dont think preamp outputs are as efficient.. Fonto.. i dont quite get what your saying...what do you mean move the RCAS are back to the right? I have 17' RCAs, so its hard to move them around. Do you guys think I can cut and solder them w/o sacrificing sound quality or performance? let me know what you think. I cant afford new shorter ones. I paid money for these things!

 
Rep Power: 329

He means move them away from interference.....your HU probably has a fuse holder on the power wire, so if your RCA's are sitting close to that you could be getting some noise. Could also be bad RCA's....if you have friends with an extra set or something try to swap them. I would think it's a configuration issue though, since its fine if you unplug one set. At this point, I would say just run your amp off one set of RCA's and live without a fade option....

 
Rep Power: 0

Oh really? It wont sacrifice sound quality or anything if i only use one set? Cause I do notice the back speakers still work if i unplug one set. Thats weird. So what exactly do I do to to do it right? I dont need a Y cable do I? I have a couple here.. shoudl i try that?


Its not totally fine using one RCA.. the loud pop pop pop goes away, but theres still a slight hum if you rev it. And yes my constant 12v wire going to the HU does have a fuse... and the wires do sort of run close to it, but theres nothing i can do about that cause everythings in a small space back there.

 
Rep Power: 0

And Mystic, what exactly do I do to get rid of that loud pop has i turn the ignition key to on? Could that blow my speakers? Sounds really scary...

 
Rep Power: 0

and the RCAs are brand new. One schoche twisted strand and one rockford fosgate twisted strand.... expensive stuff... i swapped them using the "One RCA" configuration, and both work fine if used alone.

 
Rep Power: 329

Set the amp with the switch I mentioned earlier to the 2 channel mode, and just hook up one set of RCA's...usually to the front inputs. That should distribute the signal evenly to both outputs. It wont affect volume at all, the only thing it changes is your ability to fade front to rear. When you change it to 1 RCA, I bet the pop you get when you turn the ignition on goes away.

 
Rep Power: 0

Ok, the whine I still think is coming from a bad ground. Just grounding the amp to metal isn't always enough, it is usually necessary to actually ground it to the chassis of the car. Also don't make the ground cable any longer than it needs to be. If you have a fair amount of extra slack in it it will help to cut it a little shorter. If it still does it you may have a ground loop somewhere. Crutchfield has a decent explanation of what may cause the whining here: http://www.crutchfield.com/S-hd0IamW...ech/kb348.html

As for the RCAs, make sure the settings on the amp are correct. Because from what it sounded like, is right now even after you said you checked the switch for 2 channel or 4 channel, it sounds like it might still be 2 channel. If you set it to 4 channel and all 4 speakers are plugged in and you only use 1 rca cable you should not get sound out of either the front speakers or back speakers. I would just double check your amp settings. I may be wrong though. Good luck!

 
Rep Power: 0

Dups, tried everything. Thanks. As far as my ground cable goes, it IS sort of long about 1 1/2 ft... and mystic, the pop comes on regardless of what I do. I will try regrounding though. Thanks!