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RCA Ground Loop Noise Isolator

98 Reviews | 9 questions - 12 answers


Our take on the PAC SNI-1

The SNI-1 preamp noise filter plugs in between your receiver's preamp outputs and your amplifier.

Engine whine coming through speakers in my Pontiac G8 GT was COMPLETELY ELIMINATED! Thank you!!!

Mitch, Culpeper, VA

What's in the Box:

  • Noise filter w/ 11" RCA input leads
  • Instructions

PAC SNI-1 Reviews

Average Customer Review(s):

(98 Reviews)
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Hands-on research

Product Research


  • Use when noise is caused by ground loop through patch cords
  • Brown wires are optional grounds
  • Plugs in at head unit end of RCA cables
  • Provides 1.3dB of signal gain to compensate for any signal loss that may occur due to additional connections in the signal path
  • 20-20,000 Hz +/-0.5 dB

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.

Q & A

Customer Q&A

Crutchfield asked  
Why did you buy this?

Easy one stop shopping and support. MAny choices, styles and cost, Easy check out and quick service. Im trying to eliminate ground noise. [ F  Jun 21, 2017 ]
Engine noise coming through the speakers after hooking up the Sound Ordinance M75-4 amplifier. Tried regrounding the amplifier and the HU. Reran the pwr cable also. Managed to minimize the engine noise significantly, but it's still there barely. I know it's there and it's driving me mad. I really hope this works. [ G  Jun 03, 2017 ]
got some whine thats throttle dependent in my system. have 2 mids/high amps, and both have same noise. tried everything, so this is last resort [ Randall  May 15, 2017 ]
Crutchfield had and info post about engine noise [ RJ Popham  May 04, 2017 ]
To add axillary to factory car stereo so I can connect to my phone [ George  May 01, 2017 ]
Spoke with a gentleman from technical support and after discussing my problem and doing some troubleshooting, this is what he recommended. [ Raymond  Apr 28, 2017 ]
Ken recommended it because I was getting a buzzing sound from my Speakers that were coming from my Fusion Subwoofer. [ John  Apr 23, 2017 ]
Didn't need it came with the kit [ Andrew  Mar 23, 2017 ]
To hopefully remove hissing sound from my system [ Mike  Feb 21, 2017 ]
New head unit, amp, sub and speakers. I have tried everything and cannot get rid of the whining noise, hope this works. [ David  Jan 29, 2017 ]
Came with hthe kit. Isolates unequal ground values between chassis... a good thing if you don't like whiny car audio [ Leonard  Jan 16, 2017 ]
The PAC controller i ordered is causing noise in the factory sub [ Nick  Dec 09, 2016 ]
I want to see if it actually works, im picking up a lot of alternator noise through my headunit, ive done everything from running all new grounds, using high shield RCA cables, checked the impedance between my headunit and amp, ive gone through everything I can and as a last resort im purchasing this to see if it will eliminate the alternator noise im hearing. [ Caleb  Oct 02, 2016 ]
noise reduction in a HD Road Glide after market radio and amp [ Kevin  Sep 23, 2016 ]
Works great. Clean sound. Easy to connect. Must reconnect every time it does not automatically connect when powered on. [ EDWARD H  Sep 22, 2016 ]
I needed a ground fault eliminator and I wanted to buy it from Crutchfield. [ Scott  Sep 12, 2016 ]
A Crutchfield expert recommended me this to end with my rainy static noise. [ Javier  Sep 08, 2016 ]
Function [ ROBERT  Sep 07, 2016 ]
Eliminate any possible whine or pop sound in the speakers [ Dale  Aug 03, 2016 ]
PAC's reputation and Crutchfield's great customer support [ JESUS G  Jul 16, 2016 ]
Good reveiws [ PHILLIP  Jul 13, 2016 ]
I like the insallation method, and reviews [ PHILLIP  Jun 15, 2016 ]
I have popping sound in my speakers when switching sources, on/off, changing tracks on cd's, etc. after new stereo installation. All research points to this item which has great reviews for stopping this type of noise due to a ground loop problem. After triple checking, all ground wires are properly connected. From what I have read harnesses that change regular wiring to RCA type connectors for the speakers/sub connection to the new head unit can cause this. [ TIM  Apr 21, 2016 ]
I have alternator whine and the PAC will help alleviate this problem. [ Willard C.  Apr 10, 2016 ]
Needed because there is noise in the radio. [ Corlett  Apr 08, 2016 ]
the best I found also Crutchfield are great to deal with [ Gary  Apr 05, 2016 ]
its the only thing you had to do the job i need [ denis  Feb 27, 2016 ]
Used this to cancel any potential electrical noise from the chassis grounds. [ Josh S  Feb 04, 2016 ]
i have used this product in earlier installation and it did the job. works great cured the problem I recommend it for any feed back noise [ NICHOLAS A  Jan 09, 2016 ]

9 questions already asked

it worked for me. i installed an after market radio and ended up with alternator whine. this installs between you head unit and the speakers. i put phono plugs on my left. and right speaker outputs and plugged into this unit... [ Don  Oct 13, 2016 ]
Yes, you can also plug the PAC SNI-1 into your equalizer's RCA output instead of the head unit if ground loop noise is occurring from the EQ. I hope that helps! My bio: [ Larry  Oct 05, 2016 ]  Staff
This product does not have any audio controls other than weather you connect the brown wires or not. You may want to look into sound processors to help restore the bass. Those are good about reducing the noise floor in the audio itself so they should help with that part too. I recommend calling an advisor on 1-800-324-9695 to discuss those products. HTH! My Bio: [ Paul  Sep 19, 2016 ]  Staff
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. They can walk you through the settings on the product and see if there may be a fix. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer. You can also post your question in our forums: Or try our online support center: [ Krissy  Mar 13, 2016 ]  Staff
When installed properly, no; not negatively anyway. Sound quality should only improve once the ground loop noise is eliminated. Hope that helps! [ Ryan  Dec 17, 2015 ]  Staff
I forwarded your question to an Advisor and they responded with the following: The PAC SNI-1 will eliminate interference and noise of all kinds that is created from a ground loop problem. If you are running an amplifier or amplifiers then this is the best solution in most cases for eliminating the noises that you have mentioned. Some cars with factory amps, like Mustangs for example need a 12V to 5V converter instead. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy  May 11, 2015 ]  Staff
I have a monoblock running my 12 and a 4channel running my door and rear deck I started by unplugging the RCAs from the amp to see which pair would eliminate the sound once I found it installed only one and all noise was gone hope this helps I know it helped me [ rene  Mar 30, 2016 ]
No you need two. [ REID  Mar 18, 2015 ]
Sorry, I just realized what this was. You need one for each amp. In my case, the amp would sense no signal when I changed channels and would turn off. Then when the stereo started playing the new channel it would turn back on. Huge noise problem changing channels. This filter delays the the signal from disappearing so the amp doesn't turn off and you will want one for each amp. So yes, each amp needs it's own filter. Worth the money! [ KENNETH  Mar 18, 2015 ]
I had only one amp for two sub speakers. I would think you would need one for each amp with a red/white right/left for each amp But you could split it as a low input. My setup was for rear bass only. You may be able to use only one as a low input to two subs. I would refer to the wire diagram that came with your equipment. [ KENNETH  Mar 18, 2015 ]

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