well my punch 400.4 in finally in. now i have a question. i can hear this faint whining sound coming from my back speakers. and the interesting thing is that they go in sync with my car. everything the car shifts, the sound dims then slowly gets louder.

what could this be? should i just turn the power down on the amp?

when i turn the volume to zero, that whining pitch is still there. but when I turn the deck off, its gone. it has to do with the amp.

thanks.

 

Probably your ground.

 

No f***ing way!! I bought a Punch 400A4 and had the exact same problem. I ordered it from crutchfield, installed it myself along with 2 sets of JBL components and some subs. It sounded awesome until I started my car. TERRIBLE engine whine. I worked on it for close to 20 hours moving things around, re-grounding it, checking my RCA cables, changed my battery, etc....

Finally, I used my older Punch 40 with all the same hookups and it is quiet as can be. Eventually, after nearly 3 months I sent the amp back to crutchfield. Took a little arguing but they took it. So, I went an bought an Alpine V12 yesterday and have a different problem, not a whine but a constant hum. I am returning this amp today and am just going to run my Punch 40 to my JBLs and leave my subs out.

I can swear it could be a problem with the amps. I wasnt installing this in my TL though, I was installing it in my Integra. Maybe it cannot handle that big of an amp without picking up noise.

For your problem, try regrounding it, make sure that your RCAs are not run next to your power wire. Wierd that you are only getting it in your rear speakers. I assume you are using all four channels.

 

I'll tell you you're problem if this is the case....are u using the stock head unit? If so, you used a line converter, correct? There's your problem, the line converter itself.

 

Sounds like a noisy power supply, and poor power filtering in the amp. Maybe a capacitor is in your future.

 

Streeteffectz,

I if you were answering my post on the Punch 400a4 and Punch 40, I am indeed using a line level converter from the stock headunit of my integra. I have done this before and not had a problem ( i did this in a civiv).

Is there any way around this? I am also running a Profile Crossover which I think picks up the hum, it is less evident if I run the RCAs directly into the new Alpine I have. I just got tired of messing with it since I wont have my integra for too much longer.

Any suggestions on fixing the problem?

 

What brand line converter are you using...this is MOST LIKELY the problem.

 

Yo Ron,

Is Stinger HALOC Line Converter Good?

 

Street,
How does a LOC go bad besides ****ty quality or shorting out? It's basically a few resistors and a xfmr. Since DC can't flow thru a transformer, the DC path is cut and any noise is eliminated from the HU side. Doesn't the LOC have a couple of ground wires on the output side to ground back the RCA shields to the HU chassis. Maybe the HU chassis needs to be grounded back to the car chassis. I bet he's got a ground loop somewhere. What's your experience with LOC's - I'm planning on installing mine this weekend. What brands are the best.
thanks.

 

Alpine.

It is about 5 years old. I pulled it out of my civic when I sold it. I know the easiest way out of the problem is to buy a new headunit.

Why are the newer amps (400a4 and Alpine360) picking up the whine while the older Punch 40 is not? I originally had the Punch 40 running full range to my stocks, then I replaced them all with JBL, and it all ran fine. When I added my Profile Xover (I know it is garbage), Punch 400a4 and subs the whine appeared.

Any advice would be helpful.

How far are you from DC? I may want to get some work done on my TL. Wouldn't mind keeping the headunit and replacing all the speakers/amps with new components and subs. Obviously you would need to run line level converters for that too.

 

It's not that they really go bad, its the quality of the components soldered to the circuit board itself. A lot of line converters will pick up all kinds of signal noise and a lot of the ones that ARE NOT adjustable, put out too high a signal and interfere with the amplifiers performance....this is the case A LOT of the time when using LOCs.

Kenny, you should have no problem with that converter. BY the way, what's you schedule looking like for next week?

 

Best brands I have used are Audio Control and PAC.

 

WAIT, REALY QUICK. so what should I do to get rid of that whining? 1) Check ground? 2) Check RCA and if too close to power? 3) ......?

 

unplug your rcas and turn up your radio(do whatever you did to make that engine noise come on) to see if you still hear it
if so then its between you amp and your speakers(very unlikely)

if no noise is heard then check the rca connection between the amp headunit likely it could be the quality of the rca lines too, it could be too close to the power lines of other accessory other than the amps power line,

 

ok. i will try that. but it is not actual engine noise. it is a whining pitch that comes out of my rear speakers (probably becuase the rears are hook up to the fronts and the fronts are hooked up to the rears) that is in sync with my RPM's. strange. i am thinking it is a battery problem. a old battery. the whining might be because the amp, and/or the cables.

 

I have the same exact problem with my sony explod amp and sub. It is only heard some times.. when I excelerate and the car reaches higher rmps it get louder and higher pitched. It kinda sounds cool.. like a mini turbo . Some one told me to try grounding or groud loop isolating the alternator. Any suggestions would be apprecitated.

 

Could he redo the ground for the stock head unit? I hear Honda grounds their head units in a bad place.
How did you ground your amp? It should be as short a wire as possible (in the same gauge size as your power wire), and make sure it is making good contact with totally exposed metal (a solid part of the car, preferably, like the chasis).
By the way, I agree... Audio Control rules. EQX2. Total control.

 

jz983, I had the same problem. I tested it by plugging a separate RCA cable and running it across the interior (not under the mats, just on the seats) and into the trunk. If the whining is gone, then that means the RCA is too close to a power wire. If not, then you should check your ground on the amp.

 

thanks man

 

you pay for what you get. Don't buy cheat $h!t. If you paid a lot for your fosgate, you got ripped off cuz they're cheap, probably one of the most commercialized and mass produced amps next to alpine and pioneer. Fosgate used to be good in its hayday.....but none of this Best Buy garbage.

 

well can you tell me how to fix it or not? got mine for $204 RF 400.4

 

Have you tried any of the suggested remedies? Fosgate is not what it used to be but I am not sure I would call it garbage. I was unhappy with my 400a4 and sent it back. Not sure whats next though.

 

Well I don't know if this would help but I had a similar problem when I hooked up the NAVI voice to my amp. What I did was I grounded the shielding wire (on the RCA cords) to either the grounding wire on the stereo harness or to a metal bolt on the car. It seem to remove most (if not all) the whining noise. Hope this helps.

-nemogira

 

thank you all for you help

 

What it is with that whining noise is the alternator wind up so what u would have to do is either get a filter run a cable from the amp to the battery negative(-) instead of a chassis ground, the filter can also be an X-over