Ive recently "gone active"
Ford sync3 head unit
Pre-amp outputs flattened in forscan and taken from factory amp harness
2x Alpine PDX-v9 amps
Morel Elate 3ways (2◊200w wfr, 2x100w mid, 2x100w twt)
2x Kicker 43CWRT122 12" subs (2◊500w)
My previous setup non-active had no noise.
After switching, at first i had a constant hiss even at zero volume, coming from all speakers mainly noticable from tweeters. I have to lower the master volume on the dsp to 40 (of 66) to get it to an acceptable level. This is without engine running.
I re-routed power cables to avoid running in parallel with any rca cables. This made zero difference.
I then tried a different ground, again no difference. Ground is bolted into bare metal point and is solid. The length of cable to it could be shorter though, about 0.5m of 0awg and then another 0.5m of 4awg from a distribution block to each amp. Not sure if thats worth trying to shorten as it will make installation awkward.
The RCAs I've been using are rubbish and just what i had lying around. I replaced the primary one running the length of the vehicle to the dayton with a better but not great cable and the hiss at zero volume disappeared. Result.
Except that as soon as i add even 1 level of volume the hiss comes back. Obviously once i get to level 4 it's not noticable but i know it's there.
Next steps are to replace all the rcas with high quality cables. (Including cables from DSP to amps)
My questions are, what is the reason replacing just this one cable got rid of it just at zero volume? And is it possible that replacing the rest will get rid of it completely?
Or is it just the DSP at fault and i need a better unit, audison or helix.
Thanks for any input/advice