Check out the SMD Store @ WcCarAudio.com!

Jump to content
 
 

Sign in to follow this  
krazz619

Skar RP150.4AB Question

Recommended Posts

Got the amp hooked up to Hertz Energy 3 Way in front and TX65 coaxials in rear. From the very first day I hooked up this amp, I've always had this constant static-like hiss sound coming from speakers (more noticeable from TX65 coaxials). I've also had the amp replaced brand new from Skar so this is my second one and same exact scenario.

I have been told this is normal and not. The sound is constant and happens with the amp being powered on and speakers wired up in any channel of the amp. My Ground wires for both Skar RP amps I have, are connected to a fused 2-2 distribution block with 1 0g wire connected to the body of car, does this matter? I do not notice the hiss from the sub at all

RCAs do NOT change it.

Headunit volume does NOT change it.

Car ON or OFF does NOT change it.

My guess was Speaker Sensitivity with my coaxials having 89db(most noticeable) and my Hertz components 91db(less noticeable from Tweeter and Midrange)

This is my first time ever having a 4-channel amp in my car sound system.(I've had the amp installed for a few months now)

So I am just curious to why this happens, is it normal, what would I have to change to get rid of it (speakers or amp)? Curious if others have this too. The constant hiss is most annoying when your surroundings are quiet with no music, and with music at lower volumes you slightly notice the hiss in the background of the music.

Also noticed my computer speakers (Mackie CR3s) have a similar hiss sound, so I am assuming it's normal which is why I haven't been too concerned.

Thanks

Edited by krazz619

Share this post


Link to post
Share on other sites

Does the hiss get louder with HU volume?  If so, look to the ground from the HU, maybe add another one or improve where it is grounded.  The car's wiring harness may not be sufficient ground so you should ground the HU to the chassis and as near to the HU as you can.

  • Like (+1 Rep) 1

Share this post


Link to post
Share on other sites
2 minutes ago, Crazy 8s Drums said:

Does the hiss get louder with HU volume?  If so, look to the ground from the HU, maybe add another one or improve where it is grounded.  The car's wiring harness may not be sufficient ground so you should ground the HU to the chassis and as near to the HU as you can.

Nah the hiss doesn't change with HU volume. And it's all factory ground behind there, I did solder the wiring harness connected behind the headunit.

Share this post


Link to post
Share on other sites
2 minutes ago, Crazy 8s Drums said:

If you are using the ground in the Scion's harness, you shouldn't.  Ground it to the chassis.  I can't say that it is the problem but it sure could be...

 

https://www.scionlife.com/forums/general-tech-diy-1821/noise-free-audio-tips-47336/

Oh wow ok, I guess that makes sense. I'll change it anyways and test it out. Thanks for that info!

Share this post


Link to post
Share on other sites

Well, I don't know if this is good or bad news. But I changed the ground behind the HU and the constant static-like hiss is still there. It must be produced from something inside the amp. I'm assuming this is normal and until I get a new amp, I'll have to live with it.

Edited by krazz619

Share this post


Link to post
Share on other sites

How are your amp gains set? if set to high it could introduce noise. Have you tried backing off on the gains to see if that helps?

Share this post


Link to post
Share on other sites
3 minutes ago, bcbrassard said:

How are your amp gains set? if set to high it could introduce noise. Have you tried backing off on the gains to see if that helps?

Yeah, forgot to say that. The gain does NOT effect the hiss. As long as the amp is turned on, and a speaker is connected, the hiss is there.

Share this post


Link to post
Share on other sites
1 minute ago, Crazy 8s Drums said:

You suggested that the hiss was not volume dependent.  Does that mean that when the HU volume is at 0 the hiss is fully audible?

Correct. Volume at 0, RCAs disconnected. The hiss is constant, same volume, never changes. And when I play music and turn up volume, it stays the same volume in the background. The louder the music goes, the less you hear the hiss. Only at Mid to Low to No Volume you notice it

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×