The Hiss

Discussion in 'General Car Audio Discussions' started by Equilibrium, Oct 4, 2011.

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  1. Equilibrium

    Equilibrium Full Member

    I'll have to find something around the house that has RCA out :-S
     
  2. wingless

    wingless Full Member

    The crimp looks fine. Solder is probably not required. Solder can be bad in that it wicks-up under the insulation, making the wire stiff and more prone to breakage. The heat from solder can also damage the insulation.

    I would tug on the crimps to ensure they are solid and just insulate the lugs.
     
  3. wingless

    wingless Full Member

    My daughter uses her iPhone on my boat. I've got an iPhone to USB connector that supports that usage. I also have one that is iPhone to RCA that would work for this test.

    When I was testing my boat I used an old portable CD player, yes I am a dinosaur.
     
  4. wingless

    wingless Full Member

    When I was setting-up the kick-butt A/V system on my boat I was getting a low-level background hiss from either television.

    It turned-out that the televisions were not happy w/ the step wave inverter I was using for power. I swapped to a true sine wave inverter and the hiss was gone.
     
  5. Equilibrium

    Equilibrium Full Member

    Haha I found my RCA to 3.5mm and used my spare emachine. Still got hiss through laptop :-S, AMP ISSUE :-O :p Its all wired correctly and earth shouldn't be an issue any longer.
     
  6. Equilibrium

    Equilibrium Full Member

    Diag LOL

    IMAG0100.jpg
     
  7. wingless

    wingless Full Member

    What about removing the cap from the system?

    For example, just applying power from your beefy leads to just the speaker amp, not the sub amp and not the cap. Can that be done safely?

    Also, remove the amp remote enable from the head unit feed and jump it to the beefy 12V feed.

    That connection mode eliminates everything from the amp, just the speakers and just the PC player are connected. Please confirm that the PC is battery operated, not plugged-in for power.
     
  8. Equilibrium

    Equilibrium Full Member

    Laptop is on battery, I wont be able to run the 4ga direct because of those lugs haha. I will figure something out. Maybe bolt an extension to it :-S
     
  9. wingless

    wingless Full Member

    The battery laptop should be a clean input.

    A bolt was my thought too. Pick a size that will fit into the amp power terminal, then use a nut and washers to capture that lug, then insulate the whole thing w/ electrical tape.
     
  10. Equilibrium

    Equilibrium Full Member

    So today I realized that when the head unit was mounted into the dash it would touch a bolt within the dash unit and cause the alternator whine to be extremely noticeable. This was fixed by earthing the headset to the chassis again, Instead of the battery. The whine is almost unnoticeable now, However the hiss is still present. I can live with the hiss as it's only noticeable at very low volume and between tracks/pauses. Not ideal but at least I can get some use out of the setup haha. Very frustrating. I will try that thing with the cap at some point.
     
  11. Equilibrium

    Equilibrium Full Member

    Tried taking the cap out of the loop, Still hissing, Possibly worse.
     
  12. wingless

    wingless Full Member

    During the hiss test is the speaker amp connected to the head unit or to the other amp?

    Can the speaker amp be isolated, to have the remote input be removed from the head unit (provided by a local power jumper) and the power be only to the speaker amp?

    What does it sound like with no connection to the RCA inputs? What does it sound like with your laptop connected?
     
  13. Equilibrium

    Equilibrium Full Member

    Yeah, They share power and remote turn on. Shall I try the amp powered standalone running off the laptop?? I have just finished switching the sub-woofer and splits amp around to see if it was an amp issue. Still has the hiss :-< I suppose all I have left is to test the amp standalone running the splits off the laptop, If it's still there it's gotta be power?? Is there some type of filter I can put on the 4GA power to test. The power is the only thing linking the stereo to the car/alternator so if it's filtered wont the noise go away??
     
  14. wingless

    wingless Full Member

    Yes, amp power in, with nothing else connected to that power and that ground feeds, not the cap and not the sub amp. Jump the +12V feeding the amp power to the remote enable amp screw terminal, after removing and insulating the remote wire from the head unit.

    Use the battery powered laptop as an RCA input for one test.

    Use nothing connected to the RCA inputs for another test.

    Please confirm that there is no chassis connection, except for the ground up near the battery.

    Or the amp is bad.


    The capacitor combined with the "long" power and ground wires to the battery is a filter. It should be a great filter.

    With the volume on low, use a multimeter to measure the AC millivolts on the power to ground feed at the amp. Report the result of that measurement.

    If the AC millivolts on the amp power is too high, then something is wrong.
     
  15. Equilibrium

    Equilibrium Full Member

    Awesome tips man, I'll run through that this week when I get a moment free.
     
  16. Equilibrium

    Equilibrium Full Member

    I put a ground loop Iso in today, Completly fixed :-D sounds better then ever and no hiss on 1-40 no popping or crackling!!! CRISP :) Thanks for all your help man, Excellent!!!
     
  17. wingless

    wingless Full Member

    The Clarion XH5210 amplifier already has ground loop isolation on the RCA inputs.

    You added an external part on the RCA inputs to the amp? Which part?

    Glad you are all-set! Glad to help!
     
  18. Equilibrium

    Equilibrium Full Member

    Could it be that the aftermarket GLI is of higher quality then the amp internals?? otherwise I'm stumped! I'm just glad I can here my mid's and treble correctly now haha.
     
  19. wingless

    wingless Full Member

    The two things that don't make sense to me are that there was not a ground loop when feeding the amp from the laptop and that the amp already has built-in ground loop protection.

    So, I am thinking that the problem was something else, not a ground loop problem.

    Again, I am glad it is working, but am thinking there was a different root cause. Enjoy your great sound quality!
     
  20. Equilibrium

    Equilibrium Full Member

    I'll try it again without the GLI and see what happens. I did change some amp settings :-S The GLI was only $12 so it's all gud haha.