Too much hiss from speakers, what to do?

hermanjoyman, you've GOT to stop referring to a corresponding position on the gain's travel path when you are talking about your gain setting.  Nobody who sets their gains by the book should pay the least amount of attention to the gain position once it's all set.  The referral to position makes the very act of proper gain-setting suspect.Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Yeah, it's hiss or a staticky kind of sound....kind of like when you tune into a radio station with a bad signal. The thing is, you can only really hear it when the volume is turned all the way down, as you turn it up, you can't hear it anymore....I am going to turn up the gains and see If I can still hear it when I turn up the volume. I went to a installation shop and they told me I won't be able to get rid of it because it was the nature of the head unit. I know it's not the amps because when I disconnect the the RCA's from the brain unit, the hiss goes away. My friend has a Kenwood head unit also, and it does the same thing I just found out yesterday when he told me, it's a different model Kenwood, but it's a Kenwood. I just finished making the RCA's shorter, cut off about 8 feet from all 3, I moved around the power wires for the brain unit to make sure they don't run parallel to the speaker wires or RCA's, but still that hiss/static sound persists....The only thing left to do is give the head unit and the brain unit a better ground....but I still don't think that will solve it. I might finish it up tonight, might not, tired of doing all the other things already...I will let you know what happens if I do it tonight, or whenever it is I do it.

Like I said several posts ago...

DYohn wrote: While the noise you hear could be caused through your RCA cables, this is unlikely.  Much more likely is improper gain setting or poor quality ground, or a poor ground inside the head unit.  Make sure your RCA cables are not damaged and are properly seated.  Read the ground stickies at the top of this forum and make sure you have good grounds for your amps.  Run a separate ground for the HU (do not use the factory wiring harness ground.)  In fact, some times the best results can be had if the HU and the amps are grounded at the same point. It is also possible that the new HU is simply noisier than your old one.  If this is the case there's nothing you can do about it other than change the HU.

Support the12volt.com

Dude, stevedart, I only gave those reference points because Kenwood claims 5V preouts, while the Pioneer I had before claimed 4V...so, it would only make sense that the gains should have to be set lower, not higher. Setting the gain "by the book" only makes the hiss louder....the only way to do it is to set it by ear, to get the minimum hiss as possible. The amps are the same amps, so the gain on those amps is the same as it has always been. The only difference now is the head unit...obviously this head unit is the cause of the noise since it wasn't present before. The Pioneer I had before must have preouts closer to the 4V it claims, and the Kenwood must not be close to the 5V it claims, and also most likely the Kenwood must have a ground problem that is inherent to their units, since my friends does the same thing. That is the only explanation I can see.

Did you use a 12V zener diode, or a 15V zener??? I am assuming the band side (cathode) of the diode will go to ground, is that how you set it up???

I just wanted to add.....I took some measurements of the preout voltage on the Kenwood head, using an 80hz test tone, with 3/4 max volume, with all the processing off, no eq's...and I get a reading of 1.45 volts on the sub preout and 1.045 volts on the front and rear outputs. When I took the same measurements, with the same conditions on the Pioneer head, back when I was setting up the gain for that head, I read about 3.3 volts on all the preouts. So, now I have proven that the Kenwood definitely has lower voltage output on the preouts than it claims, most likely not high enough to clear the noise floor....most likely why I hear the hiss........again I ask, will a line driver help me in this case???

If you've narrowed it down to the head unit as the culprit, wouldn't it be the wisest thing to do to trade up to a better deck rather than adding another device in the signal path as an attempt to fix the deficiencies? Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.