Bad radio signal after amp installed.

[Kevin107]

Hello,

Radio (FM) was working fine until I plug the RCA output into my amp. Works fine if I unplug it, but instantly lose signal when I plug it back. I've tried to move the wires around a bit but no help. Anyone else has this issue?

TIA

 

[David Analog]

Which brand and model of amplifier?

 

[Kevin107]

JL 250/1 and Kenwoods kac-m3004
Doesn't matter which amp I connect to. Instant loss of signal.

 

[Coheeba]

Sounds like a grounding issue with the amp.

 

[Kevin107]

I'll check that out and report back. Thanks

 

[David Analog]

Loss of FM signal is not uncommon in boats and even some cars when adding an amplifier. The DC to AC to DC high-speed switching power supplies can emit a great deal of high frequency interference. Class G amplifiers are especially bad. A few decades ago, amplifiers could even interfere with electronic braking systems when the amplifier and braking module were in too close of proximity. In a car you might have a HU and antenna up front with a metal bulkhead separating and partially isolating the rear mounted amplifier. Not so in a small boat.
However, from your description I suspect that the audio system may be needing an improvement in the ground scheme.

 

[Kevin107]

Will try to tap HU ground into my ground distribution block to see if it helps.

Thank you!

 

[KXCam22]

Are the deck and the amps grounded at the same point? For a start i would suggest cutting off the factory deck ground wire and re running it to the common amp ground. Hope this helps. Cam.

 

[Kevin107]

That's my plan once I have sometime this weekend.

 

[seanmclean]

That's my plan once I have sometime this weekend.

Kevin any luck with this fix? Just finished wiring in two amps, radio worked fine before, but now just static. Amps are grounded to a distribution block and then direct to house battery negative.

 

[Seadeals]

I have the same issue after installing my amp. I also played around with ground jumpers but it didn’t seem to help. Good thing I use my iPod all the time anyway. Now I just need the Wetsounds A Link so my boat buds can use my playlist too.

 

[Kevin107]

Kevin any luck with this fix? Just finished wiring in two amps, radio worked fine before, but now just static. Amps are grounded to a distribution block and then direct to house battery negative.

I haven’t had a chance to fix it yet. I don’t usually use the radio so I haven’t try.

 

[jcyamaharider]

I don’t usually use the radio

How is this possible?????!!!!!!!

 

[Kevin107]

How is this possible?????!!!!!!!

I usually have my phone plugged in and use Spotify for my music.

 

[bronze_10]

How is this possible?????!!!!!!!

Says the guy who has 250,000 Watts and 312 speakers and can send music farther than a ham radio signal..

(Some of my details may be a little off! )

 

[jcyamaharider]

How is this possible?????!!!!!!!

I usually have my phone plugged in and use Spotify for my music.

Gotcha......radio as in FM ( as I see up top now ) not as radio referring to it as a source unit for all audio output. I thought you were boating with no music at all.

 

[Seadeals]

Any updates on this? My reception is still very sketchy after the amp install. I moved the antenna and played with grounds but it didn’t really help.

 

[seanmclean]

nope, still sucks for me. Even tried an amplified antenna mounted away from the amps.

 

[Mainah]

@David Analog per usual is spot on. Most likley the pwm in the amps. I don’t have any issue with my jl amps. Before trying anything with the antenna I would try shielded rca cables. Keep in mind this may not help much but it will certainly help the entire system some if you have that much emi going on. True Shielded speaker wire with for in wall home use may also help.
Here are some budget effective rcas to try.
Monoprice 102869 3' Premium 2 RCA Plug to 2 RCA Plug 22AWG Cable - Black https://www.amazon.com/dp/B002JTV7UM/ref=cm_sw_r_sms_c_api_7uD3AbCPQKN65