Subwoofer Pop

This is an old thread, but a search through the forums didn't seem to find any answers or updates...

I'm having the same problem - any change from Dolby Digital to stereo (ie, watching a HD 5.1 show, then a switch to a Stereo commercial) or hitting FF/RW/30 second skip on my motorola DVR (which causes a momentary loss of audio encoding as well) causes a small pop/light booming sound from my subwoofer (a Dayton 100). Turning off the sub stops the sound as nothing comes from the speakers. I'm running an Onkyo 606, but looking through the 606 forum didn't turn up any hits.

I searched the interwebs and found many occurrences of similar issues - however, they often weren't specific to just the sub which leads me to believe that maybe there's some type of change I can make to avoid this.

Just wanted to bump this again to see if anyone had any thoughts - it seems like my combination (Motorola cable box with an Onkyo receiver) is pretty common.

As an update, I changed all of my cabling (from the Motorola to the Receiver) switching from HDMI to component/digital audio and tried some different sub cables as well and I'm still getting the pop.

This doesn't seem like a defect, but it's certainly annoying...

My subs pop when they change from standby to on. I've increased the AVR sub output volume to +4dB and use a Y connector at each sub. It only happens when I go from a low to a higher volume or when the sub receives a signal from the AMP when playing music without much bass (eg piano) and the sub cycles on. This is the only time it happens in my system, which isn't very much.

I just started a new thread about this, then found this one... so, I figured I'd bump this one and ask if anyone found a solution to it -- it's really annoying...

Wow I came to the forum today to look for this exact problem. I have a Motorola DVR, Onkyo 304, and a Dayton 12" sub, and it too thumps anytime I change the channel on the DVR. VERY annoying.

Does it make the thump on the tv speakers?

Negative, it is only the subwoofer that pops/thumps. No other sources cause this problem, just the DVR.

Does eveyone on here have the same DVR?

It seems like everyone has a Motorola DVR and an Onk TX-SRx04, x05, or x06 AVR. The problem happens with almost any action on the DVR, but after working out my XBox 360, I do hear the pop several times as it goes through its start-up.

I read on another forum that someone solved this problem by doing a factory reset on the AVR (DVR/VCR + Standby buttons at the same time).

I did this, put all the settings back the way I like them, and while the popping is not gone, it is a lot less pronounced than before. I'd still like to get rid of it completely, but I'd like to see how everyone else's results are if they give this a try....

I take the above post back -- the popping is not just a little bit improved -- after further testing with different channels, volume levels, and functions on my remote, the popping is basically gone. Completely. Hopefully this works as well for you guys as it did for me...

OK, so I have to take back my take back! My wife listens and low volumes (too low for me, which is why i didn't hear it), and at low volumes the sub pop was still very audible.

Out of desperation, I grabbed a ground loop isolator i had from my car stereo install days and put it between the AVR and the sub.

This time it's for real -- ANY volume, ANY function, the noise is COMPLETELY TOTALLY 100% GONE.

For me at least, this is totally a grounding problem. These isolators are available for $10 or $15 at most anyplace where they install car stereos. If you have some hook up wire, there's a good possibility that just connecting the chassis' (chassises??? ) of the sub and the receiver will solve the problem the same way. If your sub and receiver are in close enough proximity to each other, that is....

I tried the reset and it didn't work.

Glad to hear you solved it though. Could you take a picture of how you set up the ground loop wire? I have read about that, but I am not sure what it means precisely.

I'm at my office right now, so i can't take pics, but I can definitely explain it in detail, with some pics from the internet:

There are two ways to solve this. Option number 1: Get a ground loop isolation transformer. These are available from most discount cable suppliers and other sources on the net from $10 or $15 up to maybe $30. Here's a link to a pic of one from RAM electronics which is reasonably priced:

http://www.ramelectronics.net/render...=500&padding=0

Obviously, this just plugs inline between the AVR and sub, resolving the ground loop issues and eliminating the popping noise.

Option number 2: Run a wire from the chassis of the AVR to the chassis of the sub's amplifier. Some purpose made (and usually extremely overpriced) "subwoofer cables" include an additional wire for this exact circumstance. Here's a link to some pics from Crutchfield of AudioQuest's Sub-1 cable, which has this additional wire:

http://www.crutchfield.com/App/Produ...SUB13M&g=20111

Basically any length of copper hook-up wire will do -- just loosen (a little bit -- enough to slide the wire under) any screw on the back of your AVR and put one end of the wire under it, then tighten the screw down onto the wire. Then repeat the process with a screw on the amp of your subwoofer. If you want, you can use little spade ends for a cleaner install, like AudioQuest does. This will unite the grounds of the sub and AVR, usually eliminating ground-related noises like this pop. Just make sure you get a screw that goes into the chassis, like one of the screws that might be removed to open the amp and get at the interior. Often the screws used to hold the amp inside the subwoofer are painted, as is the exterior of the amp itself, and the paint insulates the screw (and thus your wire) from contacting the metal of the amp's chassis -- see the pic below.



Good luck! Let me know how it turns out.

I have an Onkyo PR-SC886 Preamp. Although I don't have issues with my Motorola DVR and popping I do get a significant pop in my sub when powering off the preamp. Think this might be a grounding mess so I will have to see. Any suggestions for a fix would be welcome.