Hissing when accelerating

I know this is very common (at least make me feel good to think so) that hiss can apear ,whel i got mine.I have 4 amps(for the tweets,mids+mids and sub)and my worst fear came alive when i went for a test drive,i have my sub amp that gets it's power right from the battery+1Fcap,it's ground goes directly to the negative of the battery(i think i shouldn't have done that...)but all the other amps (3 Nak's and 1 RF) are powered thru distrib. block and grounded together at the neg. post of the battery,do you guys think thats what causing the hiss ?,i have runed the rca's one one side of the car and the power on the other side and i have used Stinger's top of the line Dream series patch cables.I noticed that if my gains on the amps are at the lower setting the hissing is even more pronounced but when i increased the gains the hiss is gone down somewhat.I also use an eq and a elecronic crossover.

Thank you,i kinda think i know where the screw up is i just wanna confirmation...(the reason i used battery posts for ground was that my batt. post has provisions just for that,and since the batt. is in the trunk (a la BMW) i didn't want to drill holles.

Sorry about the long posting

Sounds like you haven't properly line matched your system for all the amps and EQ's in comparison to your head unit. This article was taken from an internet site:

Level setting is absolutely critical when combining equipment of different manufacturers and capabilities. The equipment I used to test the system was pretty expensive, but it can be done by ear very easily. Here's how.

Thank Jeff,but who sells such an test cd ?,also you didn't mention about me grounding everything to the NEG post of the Battery,so that's ok ?,since the battery is in the trunk the cables are really short.

Thanks again,i will ask around as in who may have one of those testers cd.

As long as the battery's OEM negative cable has been upgraded you should not have a problem with using the OEM battery post as your ground. Did you upgrade the OEM negative battery cable to a larger gauge ? As for the CD, if you have Kazaa just type in 1kHz 0 dB sine wave and see what you get or type in IASCA TEST CD

Yes Jeff i have upgraded my OEM neg. cable with a 2 gauge Monster Cable,but my neg. cable that the rest of the amps are grounded are via 4 gauge Monster Cable with the exeption of my sub amp that has it's own grounding via an 8 gauge Monster Cable,same for the pos. side.

Again Thank you so much

Dan,

     There are several things that could be causing your problem.  First and foremost, it could be a ground loop.  If all of your components don't have the same grounding potential this can induce noise into the system.  I'd recommend grounding every single component to one single location (be it the battery post or not) including the head unit to ensure this doesn't happen.

Another problem could be your signal cables could be crossing a factory wiring loom.  If this is the case, try relocating your wiring because more often than not factory wiring looms radiate a lot of rf noise.  If this is impossible, make sure that your signal cable passes one of these looms at a 90 degree angle with a zip tie to hold it in place.  If you still have noise after all of this, unplug each component's signal leads (rca's) one at a time starting with the amplifiers, checking to see if it eliminates the noise as you rev your engine.  If it isn't the amps, plug them back into your Q and unplug your Q from the head.  If this solves the problem, then you know the noise is being introduced between the head unit and the Q, or at the head.  If not, then check the Q's grounding.  It could also be a component mismatch due to the variations in grounding systems used by manufacturers.  If this is the case, replace with a better quality Q.

If none of this solves your problem, I could think of several other things that could be problematic, such as your ignition system.  Give this a try first and if it doesnt help e-mail.

Thank you JellyNuts,i will give it a try,but you see because my battery is in the back of the car i do have two separate grounds,the HU and two other components are grounded at the front of the car with a good and heavy power cable plus i used a gold plated eyelet for long term contact,the hiss i found to be barely audible at one seting point,but i will try everything.

Thank you.

Thats ok.  You dont  have to literally ground every single compononet to the same ground.  All you have to do is run a pigtail between all of your components, and chain all of them together.  This could be a piece of 12 or 14 gauge wire, nothing drastic.  You also do need to adjust the gain of each component starting with the Q and working your way the the amps.  You can get a small amplified speaker at Radio Shack with a 5000 ohm input on it.  All you need to do is connect this to the line output of your head unit (make sure to set your bass, treble, or any other EQ settings to flat (0 db), and using a 1KHz 0 dB test tone turn the volume up until you hear audible distorion.  Turn the volume down until you hear no distortion... this is your MUL (Maximum Uninterruptible Level). Turn it down a few more notches after that to leave yourself a little headroom.  Unplug the speaker then plug your Q into the head unit.  Plug your speaker into the line output of your Q, making sure that all your frequencies are at flat (0 db).  Making sure that your head is still at it's MUL, turn the gain up on the Q until you hear audible distortion, and then back off until you hear no distortion.  Again, back off just a hair.  Unplug the speaker and plug your amps into the Q, leaving all freqencies flat (full range) with no bass boost or hp/lp.  Next, attach the speaker to one speaker output channel of an amp.  Since it has an input impedence of 5000 ohms, you dont have to worry about barbequeing anything.  Turn the gain up until you hear distortion, and then once again, back off until it is not audible.  Do this with each amp.  After you have completed this process, hook everything back up.  If your highs, mids, or lows are too loud in comparison to one another, lower the gain accordingly on your amps, instead of raising the weak section.  Now you can adjust your Q to your taste.  This should make sure your system doesn't clip and easily damage your speakers.  You will damage a speaker quicker by feeding it a clipped signal than you would overpowering it.