CRT RPTV Owners - worry about too much bass causing vibration to your set? (1 Viewer)

[Dave H]

I have a CRT RPTV (Sony KP-57WS520) and I'm getting a new center channel (Infinity Beta C360) which is 30 pounds which will sit on top of the set. Circuit City sells a center channel support which I think will do a good job of mounting it on the top of the set. However, a speaker this strong will produce more bass. In addition, I'm looking at buy a bigger, more powerful subwoofer.

How concerned should I be about too much vibration from my new sound system? This just occured to me the other day as I don't want to knock out things like focus and convergence over time. Is this something I should be concerned about?

 

[ChrisWiggles]

Well, you shouldn't be concerned about it, as the settings will drift over time anyway. Most RPTVs shouldn't have any problems here, the components like the tube mounts and lenses and all that are very very heavy and usually bolted/screwed in pretty robustly. I mean, if you took to hitting your television with a mallet, you could start to cause problems, but even then it may even be more likely to cause electrical problems with loose connections etc.

So no, don't be concerned, because you'll want to touch things up periodically anyway, even if you had no bass at all, and a ton of bass won't have much of an effect for most things. There are people with CRTs stacked together with 4 giant SVS subs in the room, and that's a very very precise convergence to get 2 CRTs at 1080p aligned, so I wouldn't worry much about a simple RPTV.

 

[Dave H]

Thanks. Is focus something that ever drifts?

Also, how about having a 30 pound center channel on top of my RPTV. Any issues here? Just wondered if the bass..vibrations causing as issue with the speaker on top of the TV.

 

[ChrisWiggles]

Everything drifts. Most people aren't picky. I am very picky, I do a full setup from scratch about once a year on my CRT projector, including full raster centering and gun aim, full focus, *everything.* Most people won't do that ever on theid display, let alone yearly. If you haven't done a full setup on your display even, the amount of drift will be dwarfed by how off it is already, IMO. I wouldn't particularly worry about it in any case, because if 1) you're not picky, then you won't know the difference and it's not setup already as it is, so meh and 2) if you are picky, then you'll already be having a pro come in to set everything up from scratch and calibrate, and will have them return in the future periodically.

edit: my list was just examples, but I did leave out beam setup, which should also be setup from scratch in the final resting place, and also checked or tweaked periodically, especially if you move locations. Didn't want to leave that out and mistakenly insinuate that beam setup isn't a concern either. Again, something most users will never know or care about.

 

[Dave H]

What about the 30 pound center channel..any cause for concern?

I had a complete ISF calibration which included convergence (something I tweak every few mos. anyway), focus, etc. a few weeks ago, and plan on having him out once a year anyway.

 

[ChrisWiggles]

Some cabinets are flimsy, so you may want to distribute the weight so it doesn't deform the cabinet and by extension the screen.

 

[Arthur S]

There is something else to consider. A really powerful subwoofer used loudly can make various parts of your CRT RPTV vibrate such that you can hear it. I have 2 very good subs including an SVS 20-39 PCi, and when I turn it up very loud, my 65 inch CRT RPTV will vibrate audibly.

I am talking 95 db loud on bass heavy material.

The other thing is at this volume, other things in the room start to vibrate and make noise. I have not spent the time to use blu tac to quite things down.

I can say that I have not experienced any noticable changes in picture quality on the TV. Convergance has stayed quite accurate.

 

[Dave H]

Also, in all reality, I don't listen to things very loudly. Maybe the dialougue stays at 70 or so db. Of course, actions scenes, etc, will spike higher than that.

Chris,

I think my TV can handle it. Also, Circuit City sells this:

http://www.circuitcity.com/ssm/OmniM...oductDetail.do


My main concern was whether a 30 pound center channel with dual 6.5" woofers, 4" mid, and 1" tweeter would cause to my vibration for the tv. But, it sounds like I should be just fine.

 

[ChrisWiggles]

Again, don't be concerned about the vibration. If anything the vibration concerns are all subwoofer related, and as I described people with a lot more demanding CRT setups use a LOT LOT LOT more subwoofer power.

Your only concern, IMO, should be the heft of the speaker. I am not familiar with how sturdy this RPTV is, but in the past people have had problems with flimsy RPTV cabinets deforming under the loads of very heavy speakers.

 

[ChrisWiggles]

you could just use a large board to distribute the weight if you are concerned. Again, I am not familiar with this display, so if it's sturdy don't worry. Just some plastic flimsy enclosures...

 

[Dave H]

Thanks for the advice, Chris!

 

[Steve Berger]

There is actually a potential problem. The screen of a RPTV is composed of two or three plastic sheets. If the screens start vibrating they can rub on each other causing a cloudy appearance as the plastic scuffs. This is a documented problem that usually occurs when a set is transported roughly when the upper cabinet twists and shakes.

I don't know if anyone has reported it happening from speaker vibrations but I moved my speakers when I found my screen vibrating (I could feel it and hear the slight rattle). I would use cabinet rattle as a determining factor for positioning speakers, myself.

 

[Dave H]

I put in Lord of the Rings - Two Towers...at the main battle...cranked it up about as higher or a bit high than I would ever listen to it. While I didn't feel vibrating, per se, I did feel reverberation...all the way to the bottom of the set.

 

[Dave H]

Well, I think I answered my own question.

My convergence is totally whacked out. I just threw in the Avia crosshatch pattern, and the convergence is majorly out of whack.

Edit: I wanted to add that as I was standing up, close to the TV, viewing from the side, I did notice a rainbow. Is this problem related to magnetics possibly? Someone on another forum -- albeit different set, but same brand speaker reported a problem with this. Infinity says the speaker is shielded, but obviously not 100%.

Another Edit: These rainbows are only present when I am standing up right near the screen and looking downward at the screen. The are not visible during regular viewing or seating.

 

[Steve Berger]

Two things, convergence is always done (after warmup) looking with your eyes at the dead center of the screen.

Second, do you wear glasses? Plastic lenses create difrraction if you turn your head slightly sideways. The screens are plastic lenses also so extreme viewing angles could cause some diffraction too.

RPTV's are fairly immune to magnetic effects and the magnetic object would need to be almost underneath the set to have any effect (the tubes are in the bottom part of the RPTV).

 

[Dave H]

Hi Steve,

Yes, I wear glasses. So, maybe that's the issue with the "rainbows."

I was just shocked to see how much my convergence has drifted in just a couple of weeks' time.

Could the center channel be causing this? I did feel reverberation at the bottom of the set.

Also, I recently had my overscan reduced to around 2.5% or so on my set. Would it drift faster now that overscan is so low? (I used to be around 4.5% overscan. Flash Focus is disabled as a result, so I have to tune convergence manually -- which I am fine with.)

This TV was warmed up for several hours when I checked convergence.

 

[Steve Berger]

I service these things and was going nuts trying to tweak my own set with my glasses on (didn't have my contacts in at the time), when I realised that my glasses were causing the problem. (glass lenses don't seem to cause the problem)

I switched to DVR's and reduced my overscan to almost nothing without any problems.

The weight on the top will cause the cabinet to distort slightly which will cause convergence changes but it should stabalize after a few weeks. I have a friend with 9 VCR's (mostly older BETA editing machines) and three SAT receivers plus a DVR on his RPTV. (custom braced shelf) It took a couple of months to settle down.

 

[Dave H]

Just in case, I'm moving my Infinity speakers further from the TV. The floor speakers will each be about three feet from the TV.
Is this a good distance to avoid any possible magnetism?

I've been reading on other forums that while Infinity are shielded, people have been having issues from them. Though they were all CRT owners, and not RPTV CRT. However, I have noticed no distortion (other than what I previously mentioned from my glasses).

Also, I'm going to get a shelf mount for my center channel speaker. The shelf mount will be behind and above my TV...as the mount will be on the wall.

Also, is it likely that magnetism or reverberation can cause changes to my focus or grayscale?

 

[ChrisWiggles]

Where is your sub located? The guns in an RPTV are usually in the bottom front. MAgnetism from a center channel won't be a problem, but if you have the sub in front of the TV or something, that could cause convergence and beam focus to move.

 

[Dave H]

My sub was about 2-3 feet to the right of my tv.

I never really noticed an issue with it before. I have now moved the sub to the back corner of the room just in case.

I do have Infinity Beta 50 standing speakers...which were about one foot from each side of the tv. Could this have been an issue?

I have now moved them so they are each 3 feet from the tv.