Axiom Home Page Forums General Discussion Technical Questions EP500 Magnetic Interference

Aloha. Wondering if any owners of direct-view CRT's have experienced interference from the EP500 subwoofer? I use the SONY KD34XBR970, and have experienced bending of both horizontal and vertical lines from my sub which is 10' away but directly off to the right side. I've pretty much concluded that the sub is the root issue, as I can see interference when viewing the OSD from my Outlaw 990 pre/pro and the sub kicks in. Also, I've had the service guy here twice now, and each time the line bending returns in the direction of the sub (down and to the right).

The driver is not magnetically shielded so you'll need to move the sub away from any CRT display.

Thanks, I'm guessing you mean further away, and that's kind of what I'm trying to poll here. How far away are other owners of larger CRT's finding they need to put the sub...?

My EP500 is only about 4' - 5' away from my 32" Sony CRT and I have no visible distortion. Here's how they are arranged.

When I was tweaking the location for the EP600, I had it within 2ft of my 27" CRT Sony, with no problem. And with the drivers location in the cabinet being so high, it was RIGHT beside the picture tube.

In re-reading your post, I have a few questions.

Are you saying that you can only see the bending when you have the OSD on and the sub is running? Does the bending change with the sound emitted?

If it was a magnet issue, the bending would be there constantly, regardless of what was audibly playing, or visually on the screen. Usually it is accompanied by discoloration as well. (Even with the sub OFF)

Shawn makes a good point.

Are you certain that the vibrations of the sub playing are not just wiggling a video cable connection, or even a loose internal connection in the pre-amp?

Thanks for all the diagnostic help. I'll be more specific: Line bending is noticeable on the tv with the cable input when viewing the "Guide" function or "Program Information" overlay from the DVR box. It is not noticeable within the underlying video. The same bending can be seen with DVD input when using callibration screens from Avia, but I know for a fact that the service guy did not adjust this input. So, I'm left wondering if the cable input just needs further adjustment, or is something causing the adjustment to change over time, with the sub being the most likely source. I've read over at AVS that owners of this tv have also experienced this line bending problem, which in some cases has been corrected via the service menu and in other cases required magnets to adjust the yolk or some other technical components. As for the interference, I have to date only seen it with the OSD input from my Outlaw 990, where the screen will show obvious distortion similar to when you vacuumed too close to older tv's - in this case when the sub kicks in. I have not seen this distortion when other video inputs are playing, but I'll pay closer attention as I try to diagnose further. The Outlaw connection to the sub is with an unbalanced new cable from BlueJeans - no obvious physical defects. At least it's heartening to hear that several of you have placed the sub very close to your CRT's without incident. I'm going to have the service guy come again, and adjust the cable and dvd inputs further, and confirm with a good source like Avia. Hopefully then I'll be better able to determine if there is drift over time. As for the interference seen from the Outlaw OSD, it's not so much a viewing problem (the osd is only for setup changes), but I would like to diagnose if there is a problem with either the cable or pre/pro. Again, thanks for all your help.

Woah... how did you NOT shake the tree off the sub? I'm sure a few ornaments came close to rattling off!

OK. So, the distortion you see when the sub kicks in, is definitly a separate problem from the bending.

I *think* I can confidently say that the bending is NOT the subs fault, but an issue with the TV/tube itself. At 10' away, the sub can't magnetically affect the TV. As a test, take a small magnet and bring it close (not too close) to the tube. Notice how the image bends and discolors? Notice when you pull the magnet away it goes back to normal?

Regarding the distortion when the sub "kicks" - This is either a loose connection or cold solder joint in the video path of that particular input. (Either in the cable itself, or on one of the circuit boards)