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RCA Ground Loop Noise Isolator

Item # 127SNI1

Item # 127SNI1

In stock

About the PAC SNI-1

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

What's in the box:

  • Noise filter w/ 11" RCA input leads
  • Instructions
MFR #SNI-1/50

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PAC SNI-1 reviews

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Crutchfield response

<< >>

More details on the PAC SNI-1

Mark G.

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

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Customer Q&A

14 questions already asked

Subwoofer hum when splitter is used to dual subs. Will this fix it?
[ New User  Mar 18, 2020 ]
1 answer
Hi Nicholas in my case it worked perfect for my problem,good recommendation by the customer support team the humming when away good luck
[ RICARDO J  Mar 18, 2020 ]
Will this help with the buzz and hum coming from my karaoke laptop to my rca input in my mixer ?
[ Bubba  Dec 21, 2019 ]
2 answers
Hi Tommy, thank you for your question. This could solve the problem you're experiencing, but in order for us to be sure that this would be the best product for you, we suggest reaching out to a member of our Pro Audio department. Please chat with us online or by phone at 1-800-324-9695. An Advisor will be able to connect you with that department.
[ Jess  Jan 05, 2020 ]  Staff
First, verify that the buzz/hum is indeed coming from the RCA connections. If so, and if your karaoke machine has an external common chassis connection the this should eliminate the buzz/hum being created by the ground loop. Good luck with it.
[ Chris  Jan 03, 2020 ]
Will this help with the buzz and hum coming from my karaoke laptop to my rca input in my mixer?
[ Bubba  Dec 21, 2019 ]
2 answers
It is common for a laptop to cause hum in audio equipment. Try unplugging the power supply from your karaoke laptop and see if that eliminates the hum. If the hum goes away, one on these should eliminate the hum when the laptop is plugged in. I bought a few of these recently and they worked very well, as well as the more expensive 'hum busters.'
[ Gary  Dec 21, 2019 ]
I used this in my Silverado to quiet ignition noise.. it might work for this...???
[ C  Dec 21, 2019 ]
will this stop alternator hum?
[ Tate  Mar 24, 2019 ]
2 answers
Yes. Had a terrible hum in my boat, and the Crutchfield advisor recommended this for me. I was skeptical, but man, did it do the trick!
[ John  Mar 24, 2019 ]
This helped mine, it does slightly lower overall volume but compared to the hum it was a very acceptable trade off.
[ Mark  Mar 24, 2019 ]
This says it works in the range of 20hz-to this going to limit my input then output to my speakers which are rated to 40khz?
[ Andrew  Oct 02, 2018 ]
2 answers
Hello, Andrew! My understanding is that 20k is the high end of human hearing, I think the only one who will hear any difference is a dog.....:o) ! This part works great, sounds great. Steve
[ steve & suellen  Oct 02, 2018 ]
Yes, it will limit the frequency, but your not going to be able to hear the frequencies that will be filtered out, most people only hear in that 20hz to 20khz range anyway.
[ Coty  Oct 02, 2018 ]
i installed an aux to my xm radio and can hear alot of engine rpm noise will this fix it? and how would i install it?
[ Connor  Oct 11, 2016 ]
1 answer
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 ]
can I hook the pac SNI ground loop to my equalizer rca jack instead of the head unit rca jack? would that matter?
[ Goldie  Sep 29, 2016 ]
1 answer
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
How to stop these from killing the bass and all of the sound clarity from my speakers?
[ Joel  Sep 14, 2016 ]
1 answer
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
I'm using this with a Bose sound system equipped with a Kicx KAP-29 amplifier. The role of this additional amp is this system is to have a more kicking bass in the trunk. The main problem was the start/stop popping noise which has been eliminated by this stuff. But i'm suffering from a considerable level drop in bass after installing this. What could cause this problem and in which cases do i have to use grounding wire on it?
[ Tamas  Mar 11, 2016 ]
1 answer
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
Will sound quality be affected?
[ Calvis  Dec 14, 2015 ]
1 answer
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
Will this thing address loud popping sound heard from all speakers under the following conditions? 1. changing of audio source 2. changing volume from 1 to 0 or 0 to1 3. forward from one song/folder to next (both in CD and USB) 4. powering HD on and off 5. seeking up or down FM stations
[ Tony  May 03, 2015 ]
1 answer
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
If I have two sets of pre amps, can I use only one of these? Thanks for any info. Jon
[ Jonathan  Mar 17, 2015 ]
4 answers
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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