RCA Ground Loop Noise Isolator

Item #: 127SNI1

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78 Reviews

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

PAC SNI-1 Reviews

Average Customer Review:

78 reviews
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Need two of these for Allroad with Bose system

Written By BigChiefS4, Minnesota on Wednesday, September 23, 2015

Crutchfield Customer Review (What's this?)

Crutchfield tech told me I only needed one of these to get rid of the loud pops when starting the car and turning it off. I have the Bose system in my 2001 Allroad. Turns out that the kit uses both front and rear RCA speaker connections, so I needed two of these. Other than that, it works 100% and I haven't noticed any degradation of my music. My Premier car stereo sounds 100x better than the Bose system even when using the factory speakers and amp.


Written By Jim, North Carolina on Wednesday, August 05, 2015

Crutchfield Customer Review (What's this?)

Service from Crutchfield was terrific, as usual. But the product only reduced the alternator whine.

Major reduction in sound quality. Had to remove from system completely.

thank you

Written By Dependable Auto Service, Pennsylvania on Tuesday, June 09, 2015

Crutchfield Customer Review (What's this?)

products where fine, they are supposed to work. The real value was there tech support and shipping. i found this to be an ex elect company to deal with.

Alternator Whine

Written By John P, Pennsylvania on Monday, June 01, 2015

Crutchfield Customer Review (What's this?)

The alternator whine was totally eliminated. The "pain" is over. Can now enjoy my music at any level of volume.

Pros: No more noise.

Cons: None.

They work amazingly well, BUT you will notice a decline in your sound

Written By Slick, Denver, CO on Friday, May 29, 2015

Crutchfield Customer Review (What's this?)

I have a 2001 Audi TT with a Bose sound system. I installed a pioneer head unit DEH 80prs in place of the old factory unit.

I got loud popping noises with every button I pressed or station I changed or source I selected the popping noise was unbearable.

Techs told me it was the old style Bose amp that had trouble with the new head unit.

Well the filters eliminated the popping completely, but I noticed a loss of clarity with these enabled.

The alternative is to spend $1000 on a new amplifier parts and installation.

Pros: Eliminates popping noises completely.

Cons: Somewhat diminishes sound quality.

Gotta have it !

Written By Lucbob32, Concord, CA on Friday, May 08, 2015

Crutchfield Customer Review (What's this?)

Perfect ! Part of making it all come together !

Pros: Super easy to install, it just works !

Cons: None

PAC SNI-1 RCA Ground Loop Noise Isolator

Written By Gino, 30045 on Saturday, April 25, 2015

Crutchfield Customer Review (What's this?)

Very good. Does the job.

Cons: None

Great product!

Written By m321p, Florida on Thursday, April 23, 2015

Crutchfield Customer Review (What's this?)

Got a new Pioneer radio from my 99 MB SL500 w/ Bose system. There was a pop w/ turning it on, changing settings, etc. I called Crutchfield tech support and they told me to get 2 of these. I installed them and the pop is gone.

Pros: Good product.

Cons: none

Pac sni-1

Written By Jeremy, Port Hadlock wa on Wednesday, April 01, 2015

Crutchfield Customer Review (What's this?)

Great product, receive quickly, easy install!

easy fix

Written By Anthony S, Illinois on Sunday, March 22, 2015

Crutchfield Customer Review (What's this?)

Easy connection. Eliminated a slight alternator whine as well as a high-pitced tone from my Kenwood DDX 371 receiver. Could not eliminate the noises despite multiple different grounding points to chassis, as well as grounding RCA pre-outs. Receiver connected by RCA pre-outs to OEM bose amp on a 2001 ML320. Sound is crystal clear now with no distortion even at max volume.

Pros: Easy installation. Just plug it in.

Cons: None so far.


Written By David, Bristol Va on Monday, February 23, 2015

Crutchfield Customer Review (What's this?)

These babies got rid of the hum in speakers and the pop when tuning off ignition

Pros: does what they are suppose to do

Cons: wire is bulky and hard to fit behind radio as a result

Pretty much worked

Written By Mike M, South Carolina on Monday, February 16, 2015

Crutchfield Customer Review (What's this?)

I put these ( I had a four channel head unit) into the line level circuits right after the head unit. I had to ground them to the head unit chassis to pass the signal properly. They eliminated the alternator whine but not all of the ignition click hence the 4 stars. I had to cut the gain on the amp to suppress that to tolerable levels. I'd say they were worth the price and a simple solution.

Popping Problem

Written By Ed B., New Jersey on Sunday, February 08, 2015

Crutchfield Customer Review (What's this?)

Had a pop through the speakers after installing a Kenwood Deck from Crutchfield. After trying different ground points with no success, tried one of these and solved the problem. Mine popped when changing from Fm to Am. Easy fix.

Pros: Easy install and worked as advertised

Cons: none


Written By charles, Ohio on Wednesday, January 21, 2015

Crutchfield Customer Review (What's this?)

After new head unit install of a new alpine deck only had 1 issue and that was the loud pop sound when I changed radio stations or turned of deck ,after 5 min install , hooked system back up turned on turned station no more pop , RELIEF !! at LAST ! great product.

Pros: took care of issue in minimal time .

Cons: none

Fixed Subwoofer Rumble

Written By Ron W., Summerville SC on Sunday, January 04, 2015

Crutchfield Customer Review (What's this?)

Had been experiencing loud rumble coming thru my powered sub for about a year. Particularly noticeable when idling engine but also while playing music at low volumes travelling at any speed. Became so severe that I could not enjoy listening to music anymore. Installed this GLI and it eliminated the problem.

Pros: Extremely easy to install. Works well.

Cons: None


Written By Brendan, Bristol, CT on Sunday, January 04, 2015

Crutchfield Customer Review (What's this?)

This product works a little but does not solve the problem 100%. I think it is just covering up the problem you have rather then completely solving it. I am not 100% satisfied.

Pros: Cut some of the noise out of the speakers.

Cons: Did not take care of all the noise which is still annoying.

Crutchfield response on Monday, January 05, 2015 We forwarded this review to our Technical Support team for follow-up. Lifetime tech support comes with every Crutchfield purchase.


Written By Dave, Belleville,Il on Sunday, November 09, 2014

Crutchfield Customer Review (What's this?)

After I installed my new Sony car stereo from Crutchfield I had a loud pop in speakers any time I turned it on or changed settings. Called tech dept who recommended this filter. Gave it to me free & no shipping! Worked great. Very good company to deal with.

Pros: Worked like it was supposed to. No more popping.

Cons: No cons

should have ordered sooner

Written By D.E.Lee, United States on Tuesday, August 26, 2014

Crutchfield Customer Review (What's this?)

After lots of troubleshooting I Installed 2 of these on front and rear outputs on my Kenwood DPX-300U receiver hooked into a JB Quart 800 watt 4-channel amp in my 2008 GMC Sierra,the very noticeable alternator whine was all gone with no loss of volume that I can tell ,well worth the money ,thanks Crutchfield.

Pros: removed all alternator whine and static with no power loss

Cons: none

Worth the money, but costs you a little sound quality.

Written By Cinman37, Washington, PA on Monday, August 25, 2014

Crutchfield Customer Review (What's this?)

It was a very good product for the price. I had an alternator whine in my 800 watt 4 channel amp that I use to drive the high and midrange speakers in my 97 Jeep Wrangler. I did not want to drill my tub for a good chassis ground location so I figured I would try this filter even though I was a bit skeptical. To my surprise it totally eliminated my alternator whine . I admit I am picky about the clarity of my sound system, I noticed after a couple of weeks that I lost a bit of clarity in my highs. I guess I had to Rob peter to pay Paul. This product will make my system bearable again until I can find the time to track down the true culprit behind my whine. In my opinion it is well worth the cost.

Pros: cheap easy fix for aleatory whine

Cons: Removed a little clarity though

Works great

Written By Billy, Melbourne, Fl on Wednesday, August 20, 2014

Crutchfield Customer Review (What's this?)

This was very easy to install and solved my problem.

Pros: Works great

Cons: None

Great product

Written By Toms, Indianapolis in on Monday, August 11, 2014

Crutchfield Customer Review (What's this?)

Great product did exactly what it was suppose to do

Pros: Easy to you

Cons: Poor directions

stop the noise

Written By jimmy, Lagrange ky on Monday, July 28, 2014

Crutchfield Customer Review (What's this?)

Installed a amp and 4 started whining after the new amp was installed I added the ground loop isolator and the noise went completely away

Pros: They work well easy to install

Cons: None yet

What a difference

Written By tc, Fredericksbur, VA on Tuesday, July 08, 2014

Crutchfield Customer Review (What's this?)

What a difference this made. The sound quality increased by leaps and bounds.

Pros: Sound noise whatsoever.

Cons: None

Does what it should

Written By Fat Chris, Houston, TX on Monday, June 23, 2014

Crutchfield Customer Review (What's this?)

These GLI's do exactly what they are supposed to. I installed a JVC headunit in my Audi S4 with Bose system and by using these between my headunit and harness connections, I have eliminated popping and engine whine that is ofter prominent after installing an aftermarket headunit while still utilizing the factory amplification system. Perfect and easy solution to an annoying problem.

Pros: Easy to install, does what it is supposed to, not expensive at all.

Cons: Kind of bulky, make sure you tuck these way back behind the unit, especially if you are using two.

right on

Written By jim, ct on Sunday, June 15, 2014

Crutchfield Customer Review (What's this?)

good tech service makes it worth the extra cost of crutchfield

Works Great No more engine noise coming through speakers

Written By DavidF., Grottoes, Va. on Thursday, June 12, 2014

Great filter for static and background noise from grounding issues.

Pros: Affordable and works

very good filter

Written By Cedric, Clinton, Ms on Sunday, June 01, 2014

Crutchfield Customer Review (What's this?)

Good and easy to put in thanks crutchfield.

Great Item!

Written By JJTM, Claremont, NH on Thursday, April 17, 2014

Crutchfield Customer Review (What's this?)

Item works great, noise is completely gone!


Written By hclaeson, High Point NC on Monday, March 24, 2014

Crutchfield Customer Review (What's this?)

Has performed to promised expectations. Would highly recommend.

Great problem solver

Written By snotbottom, Milton-Freewater, OR on Saturday, March 08, 2014

Crutchfield Customer Review (What's this?)

Had a problem when the head unit would mute the output when switching sources, this would cause the factory amp to turn off momentarily and pop when it turnrd on again. A quick call to Crutchfield support and they immediately identified the problem and got a pair of these on the way. I put them in between the head unit and amp and viola! No more pops.

Pros: Fixed popping when changing sources

Cons: A bit bulky, so I had to be careful when tucking back into the console.

Solved grounding "pop" on power off and input source change

Written By Mikey-O, NY, NY on Thursday, February 27, 2014

Crutchfield Customer Review (What's this?)

I was getting a "pop" from my speakers whenever I changed input sources or powered down my new head unit (also purchased here). Just to clarify, it was not alternator whine or traditional ground loop noise, but a "pop" or "crack" from the speakers that was always at the same volume, no matter what the head unit was set to.

The SNI-1 completely solved the problem, and did not affect the sound quality at all. I heard various explanations about why I was getting this noise, from the higher voltage of my new head unit's RCA outputs, to amplifier capacitors, to grounding issues, and had tried everything to fix it. One call to Crutchfield - solved, for free!

Amazing customer service, found a product that solved my problem and was an incredibly simple fix.

Pros: Eliminated problem noise, did not affect sound quality at all

Cons: None

Loud pop on power down

Written By iwikzn, Saint Cloud, FL on Friday, January 10, 2014

Crutchfield Customer Review (What's this?)

The speakers would crackle on power up of the amp and would give a painfully loud pop on power down. This product completely solved the issue and was extremely easy to install. Thanks Crutchfield.

best 15$

Written By bori360, Guayanilla P.R on Wednesday, December 11, 2013

Crutchfield Customer Review (What's this?)

Best product a ever got

Pros: Easy to install

Cons: None

Not bad, but not a miracle

Written By Peter, Bethesda, MD on Friday, August 16, 2013

Crutchfield Customer Review (What's this?)

A very elusive whine (not alternator whine) was cut about in half by this little box. It's much harder to detect, but not impossible. As usual in life, if your expectations are reasonable, you'll probably be happy with this. If your expectations are for miracles, you may be disappointed.

Great Cheap Fix

Written By Pat, Sandwich, Ma on Saturday, August 03, 2013

Crutchfield Customer Review (What's this?)

Works to reduce the noise completely

Pros: Reduces noise

Cons: Takes up valuable space

Source pop

Written By Jmilz, Richmond, VA on Sunday, July 07, 2013

Crutchfield Customer Review (What's this?)

Had pop in speakers when changing sources or almost anything and these immediately stopped the problem. Highly recommend if installing your head unit with an amp.

Pros: Solved problem

Cons: Little big

Great Addition

Written By TonyB, Tampa, Florida on Sunday, June 02, 2013

Crutchfield Customer Review (What's this?)

A product that does exactly as described, popping noises gone

Pros: easy install, quick connections

Cons: could be smaller box with todays technology this product should be as small as a USB wireless adaptor

Totall awesome!

Written By Mike, Tustin, CA on Wednesday, May 22, 2013

The whirl from my alternator is now totally suppressed in my 2007 RAV4 using the AUX port. Sound quality is as good as ever. Highly recommended!

Pros: Maintains high sound quality, eliminates alternator whirl without a trace

Cons: None

Didn't work

Written By Ben S, Searcy, AR on Sunday, March 10, 2013

Crutchfield Customer Review (What's this?)

Sorry to say that this didn't work in my application. I can't completely blame this unit as I later found out it was a problem in my headunit but I can't give it a better rating because I don't know how well it would've worked.


Written By johnny_n, Kansas City, Mo. on Wednesday, January 30, 2013

Crutchfield Customer Review (What's this?)

Had a source pop problem after installing a new receiver and these did the trick.

Pros: Works, easy to install

Cons: none

Solved my problem

Written By Dan, Missouri on Thursday, January 24, 2013

Crutchfield Customer Review (What's this?)

My Crutchfield advisor suggested adding these to my newly installed system as I was experiencing a loud popping sound over my speakers when I changed tracks on the ipod or CD's. The new installation had upgraded the head unit and speakers but still utilized the factory installed Bose Amp. These solved my problem.

Pros: Performed as advertised

Gets the job done!

Written By Anonymous, New York on Monday, December 31, 2012

Crutchfield Customer Review (What's this?)

If you are having alternator noise chances are this will work for you. I had this very annoying squeal that would adjust as I stepped on the gas. As soon as I installed this the noise was gone. But the thing is I didn't connect the ground that you was supposed to. The ground made it worse for some reason but no the less it still worked without grounding the RCA.

If you have a Corvette, Order these with the HU

Written By Gotts have these for a Vette, Norcross, GA on Monday, October 22, 2012

Crutchfield Customer Review (What's this?)

Crutchfield sent me a pair of these to solve my thump problem in my 92 Corvette convertible. Apparently ground loops are to be expected with a Vette installation. Would have been nice to have been told that when I ordered. I would have paid for them and saved a few days of frustration.

Pros: Work. Simple to install.

Cons: Crutchfield should change their install guides to suggest these with a Vette install.


Written By Flycast47, Aledo, TX on Tuesday, July 17, 2012

Crutchfield Customer Review (What's this?)

Not much to it they effectively eliminated the ground loop POP.

Pros: Worked

Cons: Slightly bulky


Written By Mike, Panama City on Wednesday, April 25, 2012

Crutchfield Customer Review (What's this?)

This little device is amazing!!!! I was having alternator noise in my car after installing an eq and xover. I tried grounding the rca's and changing the head unit and eq's ground, but none worked. Immediately after receiving my Crutchfield order, I installed this device between the head unit and eq's signal path and..........Wallah!!!!!!!! All the alternator noise was GONE! Magic.

Pros: Works great!

Cons: Can slightly reduces gain, but you can compensate by readjusting your amp.

Just worked

Written By Brandon, Sterling, VA on Monday, April 16, 2012

Crutchfield Customer Review (What's this?)

Crutchfield support is genius. They sent me two of these to solve my issue with my new head unit where I was hearing alternator whine (a high pitched noise that tracks engine rpm) through the speakers. These killed the noise.

Pros: Great product. Works as advertised. Also, Crutchfield tech support is second to none.

no real difference

Written By Bake, Lexington, KY on Monday, April 02, 2012

Crutchfield Customer Review (What's this?)

Probably not the product's fault, but this must not have been what my system needed because there is no discernible difference. So, just because your system has a high frequency whine that changes with engine speed, this may not be the answer. I coupled it with the S25A unit - and it apparently is not what my system needs (i.e., inexpensive Pioneer receiver, clarion 7-band equalizer, Boss 4-channel amplifier, four 2-way 6.5" pioneer speakers in an old Corvette). I have it installed between the receiver and the equalizer - so maybe if I get an additional unit and try them between the equalizer and the amp, I would get better results?

Pros: Easy to hook-up

Cons: doesn't seem to make any difference for my system

Crutchfield response on Tuesday, April 03, 2012 We forwarded this review to our Technical Support team for follow-up. Lifetime tech support comes with every Crutchfield purchase.

Wish I had this in the begining

Written By JoeA, Orange County, CA on Wednesday, March 14, 2012

Crutchfield Customer Review (What's this?)

Got my unit all installed, kept getting a pop when switching audio sources or shutting off, everyone online keep saying inline filter. I kind of wondered if so many people had this issue why was this not included in my order?

Pros: It just works, no more pop!

Cons: Should have been included in my order, then I would not have to pull it all apart again.

RCA Gound Loop Isolator

Written By Nicky C, Llano, TX on Sunday, February 12, 2012

Crutchfield Customer Review (What's this?)

Had a problem with new receiver making a popping sound when changing tracks on the CD Player. These took all the noise out, and they were easy to install.

Ah, just what I was looking for

Written By DanielC, Sausalito, CA on Wednesday, January 25, 2012

Crutchfield Customer Review (What's this?)

What started as a simple plan to improve my car's sound system began to unravel as a stressful, time-consuming tasks with more than I can ask for. Recently, I installed a Kenwood KDC X395 headunit along with a new subwoofer and amp. After the installation was complete, to my disdain, there was very noticable humming and alternator noise coming through the speakers. The car audio shop pretty much told me I would have to bear with the noise in a polite way. So I did, for two weeks until I could not bear it any longer. That's when I called in to Crutchfield to help me resolve my specific problem. The customer service rep layed out my options for me, with me ultimately deiciding to take the ground loop isolator route. Based on the previous reviews, I was uncertain about the efficency of this product. Preparing myself for the worst, I set a low expectation that this product to work only partially or not at all. To my surprise, it completely took out all unwanted noises. All I did was disassemble my center console, connected to head unit, reattached my center console taking me less than 20 minutes. Now my audio system is officially complete, accompianied by zero interference, and I am able to fully appreciate the clean sound I have been delayed for so long.

Pros: Resolved my alternator whine, hum, and miscellaneous noise. Quick and easy install.

Cons: I have nothing to complain about.

Sub pops? This eliminates it, but.........

Written By Brice, Phoenix, Az on Thursday, November 17, 2011

Crutchfield Customer Review (What's this?)

This units says that it adds 1.3 dB of gain. Honestly, I hate to say it is a lie, but it actually cut my gain by what seemed to be half. My sub went from "awesome thumping" to " gentle bass" as soon as I installed it. As a sanity check, I un-installed and reinstalled it 4 times and compared the sound output each time, same song, same settings. Yup, definitely a decrease in the sound. Needless to say, I will not be installing it. My sub came with a remote gain control and I found out that you can just turn it all the way down before each circumstance above, to avoid the popping. I might even send in my sub to the MFG to have them adjust it for FREE.

Pros: I had an annoying pop from my powered sub every time that I would turn off my stereo, turn on my stereo, switch input sources (CD, USB, Radio, etc.), volume from 1 to 0, and volume from 0 to 1. It was pretty disturbing. I installed this unit and BAM the popping was never heard of again.

Cons: It cut my signal gain, regardless of what it says (adds 1.3dB).

Works as described

Written By Ivan T., SLC, UT on Thursday, November 17, 2011

Crutchfield Customer Review (What's this?)

This is just a band-aid for the problem but it does work and it works GREAT! I needed 2 of them for my car and as soon as I installed them the sound got as crisp as it could be. I have a 96 Nissan Maxima with the stock BOSE system in it. Upgraded the HU to Kenwood Excelon x595. The HU is awesome and it works great. however, I got some noise from the alternator when the car is started. The PAC SNI-1 units took care of that in an easy and lazy way. My problem was probably with the actual ground connections but to make them better it required a lot of work. The SNI-1 did it for me and I am happy of the results.

Pros: Works great and I got a good price for it

Cons: n/a


Written By Ray, New York, New York on Thursday, November 03, 2011

Crutchfield Customer Review (What's this?)

I installed this PAC SNI-1 RCA Ground Loop Noise Isolator in my wife's near-classic 1990 Toyota Celica GT-S as soon as I received this product in the mail. After following the Crutchfield flowchart for isolating the source of the alternator whine, I narrowed my focus down to the patch cables connecting the subwoofers to the amp. This little device completely eliminated that annoying alternator whine! I did notice that the subwoofers lost some of their "thump" and bass quality after installation, but I simply went to the amp and adjusted the subwoofer gain controls upward slightly. And - VOILA! Our music is rich, clear, and enjoyable again!

Pros: Easy plug and play installation.

eliminates noise, but also devastrates output!

Written By DMB2STEP, Wells, MN on Friday, September 16, 2011

This product came in nice packaging, and felt pretty solid. I was going to use it with the intention of killing a nasty hum &bumping noise I was getting out of my subwoofers everytime i changed sources on the HU or skipped through CD tracks. Well this thing killed the noise alright, but it also lowered my subwoofers output about 75%!!! Called product manufacturer and they claim this product is not intended to be used on a subwoofer line, so be aware before you purchase.

10 minutes to perfection

Written By Gabrial, Winnipeg, MB on Friday, August 05, 2011

Like the title says, 10 minutes to perfection. I purchased a used car with a very badly installed sound system. After correcting the mistakes of the previous installer, there was still a bad alternator whine whenever the engine was on.

5 minutes to remove my center console, shift knob and dash console, 2 minutes to hook the rca's into the isolators (one set each for rears and front, will order another when it comes to adding sub), and hook the isolator into the head unit, and 3 minutes to double check all of my connections and put my consoles back together and no more alternator whine.

Best money I've ever spent in my life.


Written By Anonymous, cincinnati,oh on Wednesday, June 29, 2011

Crutchfield Customer Review (What's this?)

Worked great & easy to install had my doubt's but it removed all my noise from speakers.


Written By Anonymous, Centerton, AR on Wednesday, June 01, 2011

Crutchfield Customer Review (What's this?)

It was easy to install and it removed ALL the noise from both my speakers and my subs. Works perfect.

Very good product

Written By Mack, New Orleans on Wednesday, June 01, 2011

Crutchfield Customer Review (What's this?)

I had an annoying pop coming through my woofer every time I changed sources on my head unit, radio, CD, DVD etc. When I installed the PAC SNI-1 it silenced that pop completely. Very easy to install thanks to Crutchfield support.

Noise gone

Written By Jerry P, Clarksville, Tn on Tuesday, May 10, 2011

Crutchfield Customer Review (What's this?)

I have used ground loop isolators before, before, but these are the best. If you
have whining noise get some. They are wonderful and easy to install.
Crutchfield support is the greatest. Pure silence and they make your system
sound great. I am very happy with the way it took care of the whining noise.

Best $15 spent.

Written By Bob, Midwest on Thursday, March 17, 2011

Crutchfield Customer Review (What's this?)

This is the best $15 I've ever spent on a car stereo system. I bought a used
car with cheap subs and cheap amp installed. The prior owner had disconnected
the sub system due to the LOUD engine noise and on/off pops. I put in a $39
Bazooka sub I had laying around (I left one of the cheap subs in the dual sub
box but disconnected as a passive radiator) and this $15 noise isolator and the
bass is EXCELLENT. I now also have "BLESSED QUIET!!" When I installed the
PAC, I noticed that the prior owner had different brand noise isolator already
installed and worried the PAC wouldn't change anything...fortunately, I was
wrong! If I had been the prior owner and tried one noise suppressor/isolator and
it didn't work, I would have also assumed the problem couldn't be fixed this
easily. Thankfully, I got this one! I did have to attach the ground wires to
the head unit chasis for it to work, as noted in the instructions.


Written By Aaron, Alabama on Thursday, January 06, 2011

Crutchfield Customer Review (What's this?)

Had a terrible POP in my 05 Titan (with the RF package) after installing the VX400.
Everytime I switched sources or the phone had some activity the unit would POP loud.
Installed these in line on the RCA's and silent.


Written By EtoileD, Brooklyn, NY on Thursday, September 02, 2010

Crutchfield Customer Review (What's this?)

Normally, you see reviews written in "Geek Talk" about electronics and you can't decide if you really need an item, since you don't see many "day-to-day",NON-Technical consumer reviews on most websites...

Well, speaking as someone who just wanted the "awful" LOUD Humming noise gone from External speakers plugged into my Mac Mini and powered by an Audio Receiver in my living room, from wanting too have sounds (audio) from my Mac Mini desktop going into "studio-quality" monitor speakers I recently bought (too drown out the loud noises from tenants in my NYC building)...

So I took a chance and bought this PAC SNI-1 Ground Loop Isolator from the guys at Crutchfield, plugged it into the back of the "Aux" port on the Receiver, then plugged in the RCA jacks from the speakers into the BACK of the PAC SNI-1 and then attached a "RCA Extension to 3.5mm Connector" into the speaker port on the back of the Mac Mini...and the Humming disappeared!!!

..and that was my brief "non-technical" review on the PAC SNI-1 isolator, bought from the Crutchfield website...Thanks Guys~! :-)


Written By Jim, Northern WI. on Saturday, July 03, 2010

Crutchfield Customer Review (What's this?)

This product removed most of the noise out of my system and i would recommend it overall.I would rather give the Crutchfield team (and Joe at tech) a five star rating for helping me with the install and noise problem.With the service i received and reasonable sale prices It would be plain foolish to buy electronics anywhere else! Thanks Crutchfield.

Works GREAT!!!

Written By Anonymous, Moreno Valley, CA on Saturday, May 01, 2010

Crutchfield Customer Review (What's this?)

I recently had the Kenwood DNX 9960 Head Unit installed in my 2006 Highlander. I noticed when driving a high pitched whine around 2200 RPM coming from the deck - it affected all modes of operation. I knew it was the alternator, an questioned the installing audio store on how to get rid of it. They said that it was just something that happens when a non-stock radio is put in (I'm para-phrasing a little here). Essentially they said it was something I would have to accept. Well, after spending a lot of money for a GREAT head unit, I wasn't about to accept that whine. So, I purchased 2 of these isolators, and wired them in - BLESSED QUIET!!! I now have NO alternator noise whatsoever, and no apparent degradation of signal quality to my amp. If anything, the sound seems "purer" than it did before. I HIGHLY recommend this product!!!


Written By James, Fairfax, VA on Friday, October 16, 2009

Crutchfield Customer Review (What's this?)

Great product. I always had a slight ground loop after installing an aftermarket headunit on my factory Bose system. I installed a pair of these behind the headunit and the alternator whine was significantly reduced.


Written By Doug, Lancaster, PA on Thursday, August 13, 2009

Crutchfield Customer Review (What's this?)

This product is outstanding! I've had problems with ground fault ever since
i upgraded the head unit in my van. Just recently I decided to bite the bullet
on these bad boys and bought 2 of them. AMAZINGLY they got rid of 99%
of the noise the only time you can hear any noise is if you turn the radio on
to an imput that you don't use, say the AUX for example, and then turn the
volume up to unseen levels, about 2-3 times the loudest you listen to it.
Other then that there is no noise what so ever. I reccomend this to anyone
who has noise problems/ground fault.

Great Product

Written By Timothy, Arkansas on Sunday, June 28, 2009

Crutchfield Customer Review (What's this?)

I recently had a car audio system installed into my vehicle. Within a matter of a week or two, I had a noticeable whine....which increased as I pushed on the accelerator. I did some research on Crutchfield and followed their troubleshooting tree.....which ended up being a ground loop problem. Therefore, I went ahead and ordered this product for my four channel amp and instantly the problem went away. I have had this product now for about two weeks and couldn't be any happier. Thanks for such a great product. BTW....there isn't any noticeable loss in sound quality....just clean and crisp sound.

No more POP!

Written By Jorge, Phoenix, AZ on Wednesday, May 27, 2009

Crutchfield Customer Review (What's this?)

I recently installed a Kenwood head unit into my 1998 Audi A8. The system would make an incredibly loud POP whenever I changed audio sources, or when I changed songs in my iPod. Crutchfield support recommended I try these. Now my stereo is perfect! Thank you Crutchfield.


Written By ronny973, Atlanta, Ga on Wednesday, April 29, 2009

WoW! I ordered this product after reading the other reviews. I have an Accord with bostic acoustic sl 60s in the front, rockford p400-4 amp and some pioneer 6x9s. I figured the whining sound was coming from the pioneer so i only ordered one of these. I detached the rear speaker rca from the amp and put in this isolator and then plugged the rca s into the back of it and wow.........whining gone!!! Great Product!!!!

Knocked down engine noise

Written By William, Rogers, AR on Tuesday, April 28, 2009

Crutchfield Customer Review (What's this?)

I recently upgraded my sound system in my 20' Mariah. Once the amp was installed, the engine noise was terrible. Pretty typical in a boat because of grounding problems. Well, I installed 2 of these at the pre-amp outs and 90 percent of the engine noise was gone. I highly reccomend these noise isolators, especially for marine applications.


Written By Matt, Wakefield, MA on Monday, April 06, 2009

Crutchfield Customer Review (What's this?)

I just installed a new JVC receiver with my old Kenwood speakers and Profile 4-channel power amp in my 2007 Nissan Frontier (extended cab). After all the work was done, the system had a nasty whine. I read the Crutchfield info on car noise and realized I had a ground loop problem. Then I installed this unit and the problem was eliminated - No noise at all! This was very simple to hook up and there was NO loss in audio quality. Note that this unit is directional - the male connectors are the input and the female connectors are the output.


Written By Christof, Spartanburg, SC on Thursday, March 26, 2009

Crutchfield Customer Review (What's this?)

Purchased this product when I bought my new AVIC-F700BT headunit. I have a 99 Lexus ES300 and they are notorious for having a lot of noise when replacing the headunit and continuing to use the stock amp. I picked up two of these, one for each set of RCA's. I have absolutely no added noise coming from my speakers. Great product, and I recommend you buy this product if you have a Lexus and you plan on using the stock amp.

Finally something that works!!!

Written By Robert, Garner, NC on Wednesday, January 21, 2009

Crutchfield Customer Review (What's this?)

The stereo on my daughters 1991 Honda Accord had a whine that would not go away. I tried everything. I put a noise suppressor on the head unit, rerouted wiring from one side of the vehicle to the other, changed terminals, etc. No matter what I tried the whine would not go away. Then I saw these puppies and decided---why not give it a try.

OUTSTANDING!!!! WOW!!! I plugged these babies in and the whine was gone immediately and has not returned since. Over 30 days later--and she's still jamming.

I think these are supposed to go between the head unit and the RCA cables. I didnt' want to go back under the dash, so I unplugged the RCA's from the amplifier, plugged them into these, and then plugged these into the amplifier---30 seconds at the most to do the install. It doesn't get any easier than this.

I'd buy these again in a heartbeat.


worked great

Written By Another-User, MI on Wednesday, September 10, 2008

Crutchfield Customer Review (What's this?)

i picked up 2 of these as a last ditch effort to take a whine out of my speakers. plugged them in, fired the car up, and the speakers were dead silent now. cranked the stereo up and everything sounded great. its very nice being rid of that whine that ive been chasing for several weeks now.

Removed popping sound from amplifier

Written By Bubba, Houston on Thursday, August 07, 2008

Crutchfield Customer Review (What's this?)

This product worked as advertised to remove a harsh popping sound from my amplifier. Each time I turned the JVC headunit on or off, my stock BOSE amplifier would pop.

Installing this filter on my pre-amp outputs solved the problem.

Don't bother

Written By lwick, Napoleon, OH on Monday, May 05, 2008

bought this hoping to remove the hiss sound I get with my Ipod connected
to my Pioneer head unit. Didn't happen. Crutchfield graciously replaced it
with the PAC's SNI-1/3.5 cable. It had great reviews, but no luck there
either. I am guessing it is in my setup or the Ipod itself (google Ipod Hiss
and you'll find tons of articles about it). Either way....this did not work for

Works Great

Written By Ryan, Las Vegas, NV on Friday, April 27, 2007

Crutchfield Customer Review (What's this?)

I bought a Sirius S50 radio that had a horrible buzzing/whistling noise whenever I accelerated or was driving over about 20mph. This completely got rid of the annoying sound and the radio sounds perfect now.


Written By deftflux, South St. Paul, MN on Monday, November 06, 2006

Crutchfield Customer Review (What's this?)

After trying everything to get rid of my alternator whine, this little thing finally did the trick! It did not eliminate the noise, but it is now hardly noticable. I did not notice any significant loss of audio quality except a little distortion which only happens when my subs are on, so it is probably unrelated or because I did not hook up the filter close to the head unit like you're supposed to, but in the trunk by the subs. So unlike me, follow the instructions. :)

I'd recommend you check out Crutchfield's articles on engine noise to diagnose your noise problem; they were quite helpful. If your noise is coming from your patch cables, this item will do nicely.

Hands-on research

What's in the box?

Download owner's manual

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

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

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