The SNI-1 preamp noise filter plugs in between your receiver's preamp outputs and your amplifier.
- Radioshack Audio System Ground Loop Isolator
- Radioshack Audio System Ground Loop Isolator
- Ground Loop Isolator Cctv
- Ground Loop Isolator Crutchfield
- Automotive Ground Loop Isolator
- Ground Loop Isolator Laptop
The GLI-RCA ground loop isolator will keep any unwanted hum when connecting auxiliary audio sources. Simply connect the ground loop isloator inline with your audio source and eliminate any unwanted noise from being amplified by your classroom audio system. Car Stereo Receivers; Car Speakers; Car Subwoofers & Enclosures; Car Amplifiers; Car Equalizers & Processors; Cell Phone Car Accessories; Satellite Radios; Car Installation Parts & Accessories; Shop All Car Audio; Car Security & Convenience. Remote Start & Security Systems; Bluetooth & Hands-Free Devices; Radar Detectors; Vehicle Diagnostics; Key Fobs.
What's in the box:
- Noise filter w/ 11' RCA input leads
- Instructions
Speaker level ground? Wiring, Electrical and Installation Help: 0: Aug 14, 2019: B: Where does the chassis ground go? Wiring, Electrical and Installation Help: 11: Aug 10, 2019: Static Hiss // Ground Loop Isolator Help: Wiring, Electrical and Installation Help: 3: May 5, 2018: D: Ground loop(s) issue with bluetooth system. Wiring, Electrical and Installation Help: 5.
MFR #SNI-1/50 REVIEWS
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Crutchfield asked: Why did you buy this?
To make sure there is no hum in my speakers [ Nicholas Aug 07, 2019 ]
Noise in the stereo [ David Mar 04, 2019 ]
I have motor like humm coming out my speakers [ VINCENT Jan 15, 2019 ]
To suppress ground loop nosie [ Carl Dec 17, 2018 ]
RCA connector on my existing filter broke internally and was intermittent. Cheaper to just replace whole unit than to solder on new rca connectors. No radio shack near me and getting this is cheaper and easier than ordering rca connectors from Amazon. [ Patrick Nov 16, 2018 ]
I don't want any noise coming from speakers, only good loud music! [ D Oct 29, 2018 ]
I have RFI and found this in the 'How to Diagnose and Eliminate Noise' Flow chart. [ Darrius D. Sep 22, 2018 ]
Getting feedback on my speakers and on DDx9905s monitor hoping this will eliminate the noise [ Joseph Sep 04, 2018 ]
Read the reviews and sounded like mine was doin as severl others and they were happy with your experience so I want to give it a shot, Thank You. [ Gary Aug 30, 2018 ]
I am hearing noise through my speakers coming from the alternator. Crutchfield support recommended I try this product to help eliminate the noise after I tried an active power filter which helped but didnt fix the problem completely. [ MICHAEL Aug 15, 2018 ]
Receiving Engine Noise through speakers. [ MARY Aug 13, 2018 ]
Want to eliminate unwanted noise [ Zachary Jul 25, 2018 ]
No matter where I grounded the amp rack, if the lead was longer than a few inches, which is not practical, there was ground loop noise. [ Eric Jul 06, 2018 ]
hopefully this will cancel out the noise at low volume [ Robert Jun 18, 2018 ]
I have motor noise in my truck stereo. I am hoping this will fix it. [ Kevin Jun 16, 2018 ]
Brand Name [ David A. Jun 13, 2018 ]
to eliminate line noise/ Pop from amplifers turning on. [ James Cody May 26, 2018 ]
experiencing subwoofer hum [ Harold Apr 30, 2018 ]
Well I needed supplies to reground all my wires so that I could get rid of this engine whining in my speakers. So I went to Crutchfield and saw they had what I needed. Plus they hooked me up with a 50 dollar gift card for doing a survey. So I went ahead and purchased what I needed and kept it pushing=] [ Carlos Apr 12, 2018 ]
Have a whine through my speakers [ Steven Mar 06, 2018 ]
Engine noise after installing new amp [ Harold Dec 19, 2017 ]
Shane in technical support recommendation [ William Nov 10, 2017 ]
Recommended by Xterra forum member for Fosgate Amp option [ Jefferson Oct 08, 2017 ]
Noise in my sound system. Recommended by Crutchfield associate. [ JAMES Sep 06, 2017 ]
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 ]
SHOW MORESHOW LESS11 questions already asked
will this stop alternator hum?[ Tate Mar 24, 2019 ]
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!
This helped mine, it does slightly lower overall volume but compared to the hum it was a very acceptable trade off.
This says it works in the range of 20hz-to 20khz...is this going to limit my input then output to my speakers which are rated to 40khz? [ Andrew Oct 02, 2018 ]
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
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.
How big is this filter? I need to filter my front and rear speakers (only filtered the front and am still getting engine whine from rear doors) but I am running out of space in the dash behind the radio! Are these small or do you have dimensions? What I am hoping is that these are smaller than average--if so I will get 2! [ Bryant Jun 14, 2017 ]
They are about an 1 inch thick and about 1 1/2 long I got two to fit behind the head unit. Good luck.
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 ]
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...
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 ]
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: http://www.crutchfield.com/Support/Bio.aspx?bio=159
How to stop these from killing the bass and all of the sound clarity from my speakers? [ Joel Sep 14, 2016 ]
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: http://www.crutchfield.com/Support/Bio.aspx?bio=101
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 ]
![Audio System Ground Loop Isolator Audio System Ground Loop Isolator](https://foxandgrapesco-cdn-6drz229racfsh09p7h.netdna-ssl.com/wp-content/uploads/2018/06/182280786165-8.jpg)
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: http://community.crutchfield.com. Or try our online support center: http://crutchfield.custhelp.com/app/answers/list/kw/.
I had two of these from metra which each had two grounds coming off of it. I use it for the popping noise which is created when my amp turns on from replacing the stereo in my saab 9-5 with the 9 speaker system. However, after a few months of use the speakers always start to have a buzzing noise coming from them, which gets worse and worse. The buzzing isn't constant, however, it picks and chooses when it wants to.. about 60% of the time. Is this one of better quality and will not cause that to happen? [ Patrick Mar 09, 2016 ]
Since we don't carry the Metra noise filter you're referring to, there's no way to know if this PAC noise filter would work better, worse or the same. However if you wanted to try this one out, keep in mind our 60-day money back guarantee that we include with every purchase. You can find more details about our return policy on our site here: http://www.crutchfield.com/support/returns.aspxI hope that helps. My Bio: http://www.crutchfield.com/Support/Bio.aspx?bio=159
Will sound quality be affected? [ Calvis Dec 14, 2015 ]
When installed properly, no; not negatively anyway. Sound quality should only improve once the ground loop noise is eliminated.Hope that helps!
Will this thing address loud popping sound heard from all speakers under the following conditions?1. changing of audio source2. changing volume from 1 to 0 or 0 to13. forward from one song/folder to next (both in CD and USB)4. powering HD on and off5. seeking up or down FM stations [ Tony May 03, 2015 ]
Radioshack Audio System Ground Loop Isolator
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.
If I have two sets of pre amps, can I use only one of these? Thanks for any info. Jon [ Jonathan Mar 17, 2015 ]
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
No you need two.
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!
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.
SHOW MORESHOW LESSLoading articles...
Diagnosing and treating noise problems in your car audio system
Buck Pomerantz
I've been tinkering with electronics ever since I was a kid - starting with taking apart and putting back together televisions and radios. I always got them back together again and working. I took courses in radio and electronics as a teenager, and became a ham radio operator. I worked in my high school's stage crew, running sound, lights, and a movie projector. After college, I joined a rock 'n roll band as the soundman and learned how to lug around and operate the gear that helps make music sound good and loud.
Working in a music store in Austin, Texas, I spent a few years manufacturing, installing, repairing, and operating sound systems. Our customers were recording studios, nightclubs, and touring bands. Eventually I moved back to Charlottesville, Virginia and opened a small demo recording studio. In 2006, I finally came to my senses and got this job at Crutchfield. They actually pay me to ramble on, rant, and explain the things I love about music, electronics, and getting good sound.
Given my background, they put me to work writing about some of the most complex electronic products Crutchfield sells: car amplifiers, digital signal processors, wiring, professional sound mixers, and PA systems.
More about Buck
- Started at Crutchfield in 2006
- Completed our thorough in-house Advisor training, learning about the ins and outs of our various products
- Stays up-to-date by attending vendor training sessions for new products
- Earned MECP (Mobile Electronics Certified Professional) certification
- Designed and organized Crutchfield's subwoofer wiring diagrams
- Authored dozens of Crutchfield articles and hundreds of product presentations, primarily focused on car audio amplifiers and pro audio gear
- Answers the many customer questions posted in the comments on his articles
- Semi-retired soundman with decades of experience making other people sound good
- From 1999 to 2018, also worked as a sidelines video camera grip for University of Virginia football and basketball games
More from Buck Pomerantz
This guide will help you diagnose and treat problems with extraneous noise in your car audio system.
Dealing with static, whining, and buzzing
You've installed a new receiver or amplifier in your car, and now you have a noise problem. Noise in your audio system commonly comes in these three forms:
- Radio static
- Amplifier whine
- Buzzing speakers
What can you do? The trick is to determine what the source of the noise is. Noise can be introduced into your system from a number of sources. This is especially true if you have an amplifier. The type of noise you're hearing can help determine the cause.
Read over this article for some hints and explanations of what can cause noise in your system. Use it as a checklist, eliminating possibilities until you find the culprit. You can also use this diagnostic flowchart as a guide to walk you through the troubleshooting process.
And don’t forget – if you purchased your gear from Crutchfield, or purchased tech support separately, don't hesitate to call on our tech support team (have your Crutchfield invoice handy).
Noise and your new receiver
If you’ve just installed a new receiver, here are two quick and easy starting points:
Radioshack Audio System Ground Loop Isolator
Noise in your receiver is often due to a poor ground wire connection or a poorly grounded antenna.
Is your receiver securely grounded?
Improper ground is one of the biggest causes for introducing noise into your audio system. Is the ground wire located near a noise source (like a heater, air conditioner, or computer)? Is the ground wire actually connected to the vehicle's ground? Since the antenna lead can act as a ground (thereby enabling a new receiver to operate without its ground wire properly connected), the antenna lead is frequently the source of noise problems.
Radio static can be caused by antenna noise
Check to see if you're getting noise on all sources — CD, auxiliary/USB, AM, and FM.
If the noise is present only on the radio, then it's most likely coming through your antenna lead.
If the noise is present only on the radio, then it's most likely coming through your antenna lead.
Unplug the antenna. If the noise goes away, try an antenna noise suppressor (like American International's AS100). This filter plugs in-line between your receiver and your antenna, breaking the ground path between them, thus preventing noise from entering your system.
An antenna filter, installed between the vehicle's antenna and the receiver, can minimize noise entering your system from a poorly grounded antenna.
Radiated noise
If the noise isn’t coming in through the antenna, try pulling the receiver from the dash while a CD is playing. If the noise goes away, it's being radiated into your system due to the receiver's proximity to a noise producer (like a heater motor or car computer). This is often referred to as “sideway noise.”
If the noise-causing accessory has a motor, a source noise filter can be installed on the accessory's power lead to minimize radiated noise. If the car computer (or other motor-less accessory) is causing the problem, move your receiver's wiring away from that accessory to minimize the radiated noise.
Try using magnetic shielding foil (also called Mu-metal) to shield the back of the receiver or wrap the wire or component that's radiating the noise into your system.
Engine noise and alternator whine
Noise introduced through the power and ground wires connected to your receiver is called engine noise or alternator whine. If engine noise is your culprit, you may hear a whining or clicking sound. Its pitch will usually vary with engine speed.
If this is the case, you can install an alternator noise filter on the power line between the battery and the alternator to minimize the problem. You can also install a noise filter on the receiver's power lead to cut down on signal pollution (American International's S15A (15-amp, 250-watt) or S25A (25-amp, 350-watt) filters, for example). Most often, however, alternator noise comes from a loose or intermittent ground connection. See the section below about noise in the electrical system.
An alternator noise suppressor connects inline between the alternator and battery, and can reduce high-pitched whining noise that modulates according to engine RPMs.
Noise and your new amplifier
An amplifier can introduce noise into your system through a bad ground or through a poor mounting. Rubber grommets or feet can help isolate the amplifier from the chassis of the vehicle, a potential source of noise. If all else fails, install a noise suppressor. The tricky part is figuring out which step or steps to take. Please read the rest of this section and try some of the simple tests.
Where is the amp mounted?
Ground Loop Isolator Cctv
Is it near something that could be radiating noise, like a rear-mounted tuner or computer? If so, unbolt it and move it away to see if the noise stops. Remove your patch cables. If you still hear noise, check to see if your amp is isolated from the vehicle's chassis. Any contact between your amp's metal casing and your vehicle's body could cause noise problems.
Check your ground wire
Is it securely attached to the vehicle's chassis with a good contact to clean metal? Your ground wire should ideally be 18' long at most — a longer ground wire can cause noise problems. Improper grounding causes most system noise problems.
Check your gain structure
If you have an external amplifier in your system, the first thing to do is to quiet any system noise, which sounds like a constant, low hiss. First, check for system noise with the engine off. Insert a CD and put your CD player on pause. Listen to the system with the volume way down, then way up. Put on music. If you hear hiss or static in either instance, reduce the gain on your amplifier.
Pass more signal from the receiver to the amp by leaving the receiver's volume higher before you set the amp's gain. Experiment until you eliminate the hiss or reduce it as much as possible. A tiny bit of hiss is okay — you won't hear it while driving.
Noise in the patch cables
Noise can be picked up by the RCA patch cables connecting your components. To test this, detach the cables from your amp. Insert one side (left or right) of a spare patch cable into the amp's left and right input jacks (see illustration below). Turn on your system and engine.
If the noise is gone, reconnect the cables to the amp, and disconnect them from your receiver. If you hear the noise, your patch cables are definitely picking it up. Try re-routing them. Separate them from your power cable by at least 18 inches. You could try a better brand of patch cables. The inexpensive RCA cables many people use to connect their components don't have the insulation or conductivity necessary to deflect noise in a metallic, highly conductive automobile.
Ground Loop Isolator Crutchfield
How much noise your cable receives depends largely on the size of its “loop area” — the larger the loop area, the more vulnerable your cable is to induced interference. A cable's loop area is equal to the distance between its center conductor and outer shield times the length of one complete twist in a twisted pair configuration, or the entire length of the cable in a coaxial type. Consider trading your old cable for one with a twisted pair design. You'll get a smaller loop area and less noise.
Patch cables with a 'twisted pair' design help reject noise
As a last resort, a ground loop isolator (like PAC's SNI-1) can be installed between the receiver's preamp outputs and your amp to minimize this problem.
Noise and whine picked up by the power or ground cables
We discussed ground cables above, because that’s the cause of noise more often than not. If the noise wasn’t due to a poor ground or through the stereo’s antenna cable, it may be coming in through the amplifier's main power cable. Noise can be created by cable of insufficient gauge, so you might try thicker cable.
If you cannot find the faulty ground in your multi-amp system, a ground loop isolator can help minimize the problem.
Multiple amplifiers can also create ground loop problems, which can usually be solved by grounding each amplifier with its own separate wire. If you are unable to locate the cause, a ground loop isolator (like PAC's SNI-1) can be installed between the receiver's preamp outputs and the amplifiers to minimize this problem.
Noise in speaker wiring
Automotive Ground Loop Isolator
Noise can also come in through the speaker wires. To test them, turn the system off and disconnect the speaker wires from the amps. Now start the car. If the noise is still there, then it's being radiated into the speaker wires. Reposition them, or, as a last resort, shield them by wrapping them with Mu-metal foil.
Noise from the electrical system
Ground Loop Isolator Laptop
If you've tried all of the noise-fighting tips above and you're still getting static, whine, or hiss, then the problem might be with your vehicle. You might simply need to fill your battery with fluid. If that doesn't help, have a mechanic check your alternator and battery.
If your car is older and hasn't been tuned up recently, you may have ignition noise. It's a ticking noise that varies in speed as you accelerate. You may need a tune-up involving resistor-type spark plugs, shielded carbon-core spark plug wires, distributor cap, and coil.
If the noise doesn't disappear, then your ignition system may not be grounded well enough and is broadcasting ticks to other items such as your air cleaner, hood, exhaust system, etc. Chances are, grounding one of the under-hood components will eliminate the noise. With your sound system on and the car running, try grounding each of these different components of the car. It's possible that grounding one of your car's components will eliminate the noise. If so, make the ground permanent with a braided ground strap.
A very effective fix for electrical system noise is called 'The Big Three' upgrade. This is where your vehicle's battery charging wire and chassis ground wires are augmented by adding large gauge wires (1/0- or 4-ga.) to those connecting the alternator to the battery's positive pole, the battery's negative pole to the chassis, and the chassis to the engine block. This establishes better current flow and more consistent voltage, which improves your system's signal to noise ratio. It also ensures against loose or restrictive ground connections, which, as said before, are common sources of noise. Read our article about The Big Three for more information.
Noise and your nervous system
Noise problems can be very frustrating, especially when you can't wait to hear your new equipment. It helps to remember that you've just placed a very sophisticated piece of electronic gear (a new receiver or amplifier) in the middle of an extremely complex system — your vehicle's electrical wiring. Noise is just nature's way of telling you that something's out of whack. Just run down the list, eliminating possible noise sources until you find the problem.
Crutchfield Tech Support
If you bought your gear from Crutchfield, you could call Tech Support for free help troubleshooting your system. The toll-free number is on your invoice. If you purchased your equipment elsewhere, you can still get expert Crutchfield Tech Support — 90 days-worth for only $30.