Got my new SVS! It rocks, but I have a problem. HELP! (1 Viewer)

[Adam_R]

Ok, here's what I've got:

Denon 3802
Pinnacle PN6+ Fronts
Pinnacle AC Widescreen Center
Pinnacle AC500 Surrounds
SVS 20-39PCi Sub
Monster Power HTS2500 Line Conditioner

I just hooked up the sub last night and it rocks. The windows visibly shake when watching the intro to Toy Story 2. It sounds incredible. I'm very pleased.

Here's the problem:

When the volume is up and the bass hits hard, I can see some disturbance on my TV. It's doesn't look like interference. There is no static or snow, it's more like when you touch an LCD and you can see waves in the picture. Or if you give a CRT monitor a good slap on the side. I think I am using all shielded cables. Might it be that the bass vibration is causing this or perhaps I have insufficiant power and the big bass is too much load? The sub is very close to the back of my TV. I would say it's within a couple of feet. Please help. Thanks.

 

[ColinM]

I vote for subsonic interference in the CRT. I get the effect on the pod race from TPM, which has the most sustained high level bass I have right now. Looks like ripples travelling in unison with the freq's in a waterfall fashion down the screen. Subtle, but obvious.

Obviously, power demands are happening big time, but I'm on a 15A circuit seperate from the sub amp.

Nice to know I'm not alone.

PS - 27" Sony...

 

[RenoV]

Sound like magnetic interference to me, SVS subs are not magnetically shielded and have some pretty hefty magnets on them... Move the sub further away from the TV and I'm sure that will cure your problem.

 

[Adam_R]

If it was magnetic interference, wouldn't it be constant?

 

[Ron Shaw]

If it was magnetic interferance, it would be constant, and not vary with volume level. I agree with Colin, its caused from induced vibrations in the set somewhere.

 

[ColinM]

No, I don't think so in this case, but possible in others for sure. Moving it may stop the problem due to a change in proximity equalling fewer db's reaching the tube, but mag interference is constant, not just when bass hits hard and loud which is how he describes the problem's occurrance.

My sub is 8 - 9 feet away from the set, but the TV may be in a sweet spot for SPL's. Hence distortion during loud passages.

*edit*--Like you guys said!

Man we be fast!

 

[Mike LS]

What kind of TV is this?

 

[Adam_R]

It a SONY 32" Trinitron. It's about 4 years old.

Do you think this may have an adverse effect on the longevity of the TV?

 

[ColinM]

Probably. It cant be good. Not gonna kill it tomorrow, but the color fidelity may go sooner or something like that if something gets nudged out of alignment.

I've seen the phenomena 4-5 times, but the TV still looks great, although there are 4 or 5 "dead lines" horizontally. I don't know why they are there or what caused them, but I'd hesitate to say it's the sub that did it.

 

[Mike LS]

Can you feel the TV vibrating when the sub is on full? If you can (and the distortion matches it), then I'd say there's a pretty good chance that it could have a negative result on the set over time. Parts can rattle off of anything.

What type of floor system is under the sub and TV stand?

This may not help, since I'm sure most of the force that's rattling your TV around is traveling through the air, but you might be able to lower the affect a bit by putting a sheet of rubber (or other vibration absorbing material) under your TV. That would cut down on the waves that are traveling through the floor system and up the stand to the TV.

Of course, your only true fix is to move the sub. I know that may not be optimal, but I'd rather have the sub in a less than perfect position than have my TV go to an early grave.

 

[RenoV]

I'm not saying that it isn't caused by vibrations but just because the set isn't being affected constantly doesn't mean it's not magnetic interference. The voice coil in the speaker is essentially a magnet that varies in polarity/intensity depending on the signal sent to it...

 

[SVS-Ron]

Adam,

If this happens when the bass is hitting so hard your windows are shaking it could indeed be vibrating the guns on the set.

Or... and I've seen this first hand, it could be shaking YOU. Your eyes may be sensitive to the sort of vibration (like when you sneeze) that can appear to distort the TV, but when in reality it's your vision that's being affected.

Just a thought. If you move the sub to another location (recalibrate!) and you still get this effect, then I'd guess it's not magnetic interference. More than 2-3 feet separation from the sub should be enough in any case however.

Ron

 

[Johnny Mac]

Had the same thing happen to me with a poorly shielded tweeter. When it was really working hard, like during a battle scene in The Patriot, i'd get those lines of interference. Try moving it further away and recalibrate like Ron said. Remember, the SVS is just a huge electromagnet. The magnetic field is much more active when the thing is really working hard vs. when it's just sitting idle.

BTW, I have a 27" trinitron and my SV is only about three or four feet away from driver to tube. I have cranked it to -20db from refernce on several occasions with no interference. The TV is in a large pine cabinet though.

 

[Adam_R]

Thanks to all who responded!

The effect on the TV only happens when the bass hits hard, and I can feel the vibrations in the TV when it happens. I can actually feel vibrations in just about everything within a block of this sub!

Unfortunately, I can't move the sub or the TV due to the layout of my room.

Fortunately, I rarely listen at that volume.

Thanks again!

 

[Tom Vodhanel]

Adam, As mentioned...its probably just the tv being in an area of the room that has a bit of modal induced boosting. You can try putting some isolation pads under the tv if it gets too distracting. This will help if the tv is sitting on something that is vibrating to the bass. I've actually had a few discussions lately about the tv shaking(guns and screens)vs. the human eye limitations when exposed to loud bass. I've got a SVS proto type in my HT room now that is causing some tv/eye shaking of its own...but we're approaching 140s too...

Let me know if you have any other problems with the SVS,just email me at techsupport.

TV

 

[ColinM]

...but we're approaching 140s too...

dB's?
From a single unit?

 

[Johnny Mac]

LOL at Tom doing DB drags in the living room! 140 is just insane. I hope you got earplugs in and some Depends on.

 

[Doug_B]

I have recently noticed a similar problem on the top part of my TV's picture, and it appears to be related to sound vibrations, and I noticed it on low freq material the most (TS2 intro, U571 depth charges). Although I have not completed trouble isolation testing, my center channel speaker is an influence, which sits atop the TV. I did see the problem disappear using moderate volume levels (while the kids were asleep) when I set my controller's center channel setting to None. The effect was present with my center channel set to Small. More testing is needed.
Doug

 

[John F. Palacio]

"My twin 16-46 SVS's+ shook my RP so violently that the DVD/CD player on top of it would skip when playing
bass-heavy CD's at high volume. I finally resorted to a dual isolation platform for the player!

Had no way of moving the subs away from the RP. If the vibration is coming from the floor isolation of the TV will help or eliminate the problem. If it is acoustically coupled however there's not a lot except for positioning that's going to help. Bass gets through anything, just ask the many irate neighbors of super-subs.

 

[Adam_R]

Thanks again to everyone for all the help.

Tom V. - Thanks for making a great and affordable product. I couldn't be more pleased with it.