Question for Bats, or any other "installers"...

[Botch]

Why is it the most bone-headed simple projects can end up ruining an entire weekend?!? :angry-banghead: :angry-banghead:

I've got this glass shelf for my Center speaker. Its exactly the same width as my speaker, but the front sticks out 5" past the front of the speaker, and I'm trying to remove it to take the shelf to my local glass emporium to slice off 5", round the corners, and polish.

Two allen bolts go up thru the bottom of this bracket, thru the glass, and then thread into the round silver caps you see here. At first I thought the caps would pop off, revealing some kind of thin nut underneath, but I couldn't get them loose. I tried loosening the bolts from below, but the whole silver cap rotates along with it. I grabbed the edges of the cap with a newfangled Craftsman wrench with plastic-covered jaws, but couldn't hold it tight enough. Finally, I clamped on a set of ViseGrips (I knew they'd mar up the chrome but they're hidden anyway). I applied as much force as I dared (remember, its an Allen head) and for the life of me I can't break either one loose.

Does this setup look familiar to anyone? Is there some kind of trick to get these damn things loose? I would think it would be designed to loosen, as a wide glass shelf like that may need to be replaced due to breakage.

I also tried to remove the entire bracket from the wall and just leave it attached to the shelf, but as I suspected there's some kind of nut behind the wall that began spinning with the bolt just as soon as it was loose (fortunately it "grabbed" when I tightened it back in).

Any suggestions? :think:

 

[Towen7]

Did you assemble the bracket or did it come pre-assembled. If you can't free the bolt there must be some bonding agent like lock-tite on the threads. Heat and/or penetrating oil are the only things I can think of without damaging the chrome "caps". If you are willing to risk damaging them further you can try cutting a slot in the tops to hold a screwdriver blade to counter the torque of the spinning bolt.

 

[Rope]

If the glass is not extremely thick and you don't need a beveled edge? Visit the closest home improvement center, purchase a glass cutter and straight edge. Etch the 5" mark with the glass cutter, gently tap the glass the length of the etching with a small hammer. Put your fingers under the glass (both hands), thumbs over the top, pull down with your thumbs.

Rope

 

[Batman]

Initially I had the same ? as T7 about whether you assembled it or not. I would think possibly that those caps would pop off and you'd probably also use an allen wrench to hold the top half in place as you loosen the bottom or vice versa. My limited experience with glass shelving for A/V purposes, is that usually these types of rigs are pre-assembled to prevent the consumer from breaking the item.

 

[Batman]

Oh, Can you get to the hardware in the wall with a wrench if you remove the wall plate?

 

[Botch]

Oh, Can you get to the hardware in the wall with a wrench if you remove the wall plate?

I'm doubting it. I think the behind-the-wall hardware was put into place before the inset TV bracket was installed above (which went into a 14" x 14" hole, not visible in this pic). If the bracket is factory-assembled to the glass that would explain the difficulty I'm having, but sure doesn't make sense to me.

Tuesday I'm going to call the AV shop and see if I can talk to the installers, see if they can give me any ideas.

I do have a glass cutter already, but this is tempered and 1/4" thick, I could really botch that up.

While the glass was at the shop I was going to set the center channel speaker on a cooler, upright, per Flint's suggestion and see if it sounds better (or if I can even hear a difference).

Thanks guys.

 

[Rope]

Botch -

Do you know what the hardware consists of behind the wall?

If they're toggles, gently pry on the wall mount (screw driver between the wall and mount) while loosening the bolts/screws. The toggles will fall off in the wall. Buy new toggles and remount after the glass is cut to size.

Toggle Anchor:

Rope

 

[Botch]

:text-bump:

d'Oooohhh!!!!

Well, I finally remembered to swing by the AV Shop and talk to my salesman. He was pretty sure it was made to disassemble easily, and he had the same shelf set up in the salon and grabbed an Allen wrench. He mated it to the allen head underneath, started turning, and just like mine the top chrome disk turned along with it.

BUT...

He kept turning, and the chrome disk backed up and out! The whole damn thing is one piece! Its a flathead screw that drops in from the top, and the bracket is threaded; you screw it down with finger pressure and then, to snug it up, the bottom of the threaded screw has the allen socket cut into it, and you just tighten it down!

I'm very happy that, after work today, I was able to loosen the damn thing up when I got home and now have the glass shelf at my glasscutters. But, dayam, two engineering degrees and I couldn't figure this out; d'Oh!

Here's how much the shelf stuck out in front of the CC:

Here's a closeup of the panhead screw with the allen socket cut in the bottom:

And, while the shelf is being done, I set up my center channel upright and will be doing some listening tests for a couple days (that's a Monster™ milk crate, by the way):

Interesting exchange at the glass shop, too. Saleslady took the shelf and walked it to the back shop to see if they could cut/round/smooth it, and the craftsman came out and asked me if it was tempered glass. I wasn't sure, but suspected it was due to the loading, and he warned me it could shatter if they tried to cut it. I thought about it, and asked him to try, if it shattered I'd just build a wooden shelf to replace it, no biggie. He took it back again, then in about ten minutes came out and told me it must be tempered, they couldn't cut it! They etched it several times and had two guys trying to break it, but it held!
They then told me they could replicate the shelf in 1/4" glass (mine was 3/8") and temper it themselves, and it'd hold up fine (doesn't surprise me, the 3/8" shelf I think weighs more than the damn speaker). Apparently a distemper shot doesn't work on glass. So, that's what they're doing, should be ready in a couple days.

And I can confidently predict that, with a slightly thinner shelf, those &%^$@#! bolts won't thread in quite all the way, so I'll have to cut an aluminum shim plate with matching holes to place on top of the glass shelf, that's just how BotchLuck© works... :angry-banghead: But, it'll sure look a lot nicer when its all done. :handgestures-thumbup:

 

[heeman]

Botch,

It is amazing what we learn, even on the simplest things!

So.............for the $10,000 question......................


Does the MTM Speaker present a better sound stage vertical???

 

[CMonster]

So.............for the $10,000 question......................

Does the MTM Speaker present a better sound stage vertical???

I can't remember what type of speakers those are for sure but I'm thinking Monitor Audio. I just looked up the specs on the center channel from the Silver line and it's actually a 2 1/2 way with a crossover at 500 Hz. That means that one of the "midrange" drivers is really a bass driver so lobing should only be an issue around that crossover point.

My Dynaudio Focus center channel is a true 2-way MTM and it's really starting to bug me because it definitely sounds better when vertical.

 

[Botch]

Yes, they're Monitor Audios. So far tonight I've only been catching up on the news, no serious listening yet. Two questions:

a) I understand the concept of audio "lobing"; does it affect the sound if you're sitting dead-center in the sound field, or just off-axis? I rarely entertain a crowd, and if I have a date she's usually dead-center too (just not facing the screen :dance: ).

b) Vertically, the CC tweeter is 2 feet/20 degrees lower than the tweeters of the main L/R's; does this cause other, separate problems? If I should choose to go with a vertical orientation permanently, I'd be building a bracket to mount to the CC shelf mounting point, which would raise the CC speaker six inches or so, not that much.

The other scary part about going vertical: the "bottom" of my CC speaker has 1" felt "feet" attached to the bottom four corners; they would have to be peeled off should I tip it up. Then the question becomes, can I peel them off without ruining the (gorgeous lacquered walnut) finish? Will "Goop-Off" or heat safely remove adhesive residue, if any? :|

 

[CMonster]

Two questions:

a) I understand the concept of audio "lobing"; does it affect the sound if you're sitting dead-center in the sound field, or just off-axis?

Just off-axis. Any time you have two drivers operating in the same range and you are closer to one than the other you will have lobing issues above a certain frequency.

I rarely entertain a crowd, and if I have a date she's usually dead-center too (just not facing the screen :dance: ).

:icon-rolleyes:

b) Vertically, the CC tweeter is 2 feet/20 degrees lower than the tweeters of the main L/R's; does this cause other, separate problems? If I should choose to go with a vertical orientation permanently, I'd be building a bracket to mount to the CC shelf mounting point, which would raise the CC speaker six inches or so, not that much.

Ideally you'd have all the tweeters at the same level but that's nearly impossible to pull off. I suggest getting some MoPads and angling the CC up towards the listening position. When I'm serious about watching a movie, I take my CC out of the entertainment console and set it vertically on the floor with MoPads underneath to angle it up.

The other scary part about going vertical: the "bottom" of my CC speaker has 1" felt "feet" attached to the bottom four corners; they would have to be peeled off should I tip it up. Then the question becomes, can I peel them off without ruining the (gorgeous lacquered walnut) finish? Will "Goop-Off" or heat safely remove adhesive residue, if any? :|

I bet something like "Goop-Off" would safely remove the adhesive residue but I'd get other opinions before listening to my dumb ass. By the way, everything I ever learned about lobing, I learned from Flint. I then performed blind listening tests with my wife plus observations during normal television / movie watching to confirm that my CC kinda sucks ass when horizontal and I'm sitting off-axis.

 

[Botch]

Thanks, Chuck-Monster! :handgestures-thumbup:

 

[Botch]

:text-bump:

My life is cursed. :doh: :doh: :doh:




I watched a Dream Theater concert tonight, at the appropriate volume, and at the very climax of the concert (I'm not kidding) I hear a funny tinkcrikthunk, look down, and my center channel speaker is face-down in a potted plant (plastic), with a very tightly stretched cable still connected, and broken glass all over my new carpeting. :scared-yipes: :scared-yipes: :scared-yipes:


I immediately turned the system off, gently cradled my MA CC and unplugged it, and fearfully tipped it over; no dents, and all three speakers cones were completely untouched. Whew! ray:

Pics later. I guess I need to get a 1/4" aluminum plate made for this &$%^&#!! shelf; I cannot believe how such a simple thing can keep confounding me for months!! F*ck!!!
:angry-banghead: :angry-banghead: :angry-banghead:

 

[DIYer]

Sorry to hear, Botch. Glass as shelf concept never set well with me.

 

[Dennie]

Damn Botch, sorry to hear that!


Time for a wooden shelf....... :confusion-shrug:



Dennie

 

[heeman]

Jeez Botch..................not good, hope the speaker is okay???

 

[PaulyT]

What a mood-killer! Sorry to hear that, man.

 

[Randy]

Botch, damdn dude sorry to hear that, can you just make a simple wooden shelf now to replace it. I would think that would be better than aluminium (as the Brits say).

 

[Yesfan70]

Wood is good.


Sorry to hear about your experience.