Subwoofer Troubleshooting

Subwoofer Troubleshooting

I’ve had this B-52 Matrix 1000 v2 PA system for a little over a year now. It’s been a great little system for small to medium shows that I’ve done.

But, I’ve started to notice that the subwoofer is not hitting as hard as it used to. I took it to a professional who pretty much tested everything and said that it sounded just fine.

But, to me it sounds like the satellite speakers are really overpowering any bass being put out (at least more than it used to). Just to test things out, I tried connecting the PA and then disconnecting the other speakers to see if the speaker was blown. When it’s only the sub it hits super hard and is just how I remembered it.

But, when you connect the other speakers at the same volume, it’s like it’s cut in half. Same part of the song, just not as much bass.

Could it be the wires? Some kind of power issue? I’m at a loss and feel like I’m being paranoid. Any ideas on what else to test?

Does it have a phase switch? something may be out of phase. ie when the sub is going forward the bass from the tops may be going backwards or vice versa also check you cables as that could be causing the same issue. All you need to do is make sure + to + and - to - are the right way round

+1 on checking the phases.

The spider in a woofer basket is typically made of resin coated fabric & paper. This will loosen up and move more freely as the speaker is used and “broken in”. This will allow the speaker to produce more SPL after a break in period than when new. The amount of additional SPL varies…but 3dB is a reasonable planning number.

In addition, room modes can have a HUGE effect on the amount of bass that is perceived. For best results, test outdoors at least 50ft from any structures…and 100ft would be even better. Alternatively, corner/wall load the sub and test in a LARGE room (length and width > 50ft).

The back of the sub has gain controls for the L&R channels and the sub. Start with the L&R channels on about “5” and then adjust the sub until the whole system sounds in balance. Once the whole system sounds in balance, you should be able to keep that same relative gain settings as you turn the whole system up.

Also, based on the equal loudness curves…the louder you make the music, the MORE pronounced the bass will be. Listening at “inside voice” levels and listening at “full war volume” will produce two very different perceptions of high/mid/low balance on the system.

you already did the test to determine if the tops and subs are wired out of phase, and the subs failed the test. if the subs or tops do not have a phase switch, you might have to rewire the cable going to the subs. about the only thing that could be wrong is an out of phase condition. the good news is it is almost no cost to repair

Thanks guys. I’ll double check those things and try and post back.

This is why I always say avoid brands like this and Behringer. This is typical of these brands, while it’s almost unheard of with better brands like JBL or QSC.

Being out of phase can happen with any brand

These kinds of generalities are unhelpful. 15 years ago, Behringer had a very poor reputation for quality…and they got it the old fashioned way…they earned it. But, that was then. Today (and really for more than the last 5 years) Behringer produces a LOT of entry level gear that is good value for money. There are some duds, but there are also some real standouts.

The Behringer Matrix 1000v2 system is solid value for money. In the <$1000 price point for tops + sub, this is the only system worth recommending. In my view the Behringer Matrix 1000v2 system is preferable to the JBL JRX series (the JBL entry level product line). QSC has (almost?) nothing to offer a mobile DJ in the <$1000 price point…unless you want a single speaker at your gig.

Jeff Scott and I both gave setup related reasons for the OP’s issue that are independent of any particular brand.

Sounds like a crossover issue… not familiar with the B52, but on lots of other sub/satellite systems there settings for full range or crossover… maybe play with these?.. btw.. does the sub hum at all when nothing else is plugged into it.. no line feed, and no satellite speakers?

I had the same system for about a week. Guitar center, right?

Pfff. It sounds to me like possibly the built in amps are starting to go already, or out of phase like others said.

Guitar center hooked me up with 2 PV215s, 2 Crown XLS1000s, cables, and a Harbringer 18" subwoofer for around $1200…seems like a LOT more, but if you can afford it and have a nice SUV, that set up will easily blow the old one out of the water. Just a recommendation my friend!

There’s no hum by itself. There’s a ground switch for that on the back. I’ve tried turning it up a bit to see if it affects things but still get the same response.

I think the worse thing about all of this is trying to call B-52 and having their support staff always be out of the office for some reason. Do they even have a support staff?

Looks like I should just think about getting another brand.

Also, I tried messing with the phase switch on the back to see if it did anything and it doesn’t seem to affect anything.

next.. try running a simple 14 gauge or higher wire with stripped ends and connect them to the metal chassis on both tops and the sub.. this problem might be a weird ground loop issue.. when you do this mess about the the ground lift switch as well… note these connections are made at the exterior of the cases

Also, as an additional option. Could I just pick up an amp that I could use with b52 subwoofer and speakers? Not that I want to lug it all around and duplicate efforts but until I can afford to pick up an entirely new system could it be an option?