Does such a tool exist?
 

I am installing ceiling mounted speakers and I want to make sure the two units are equidistant from a wall about 12 feet away. I tried measuring using a retractable tape but it keeps falling sagging down. It there such a thing as a measuring beam that uses a light beam? Is there one that has a beam, a digital read-out and a level?

Don't get too fancy on me. I happen to like and spend a lot of money on specialize tools for my business. Find a small stick (don't use a 2x4, its too heavy)that's a little over 12 feet long and make a mark on it. Butt the end of the stick ans transfer the mark on the ceiling and do the same from the other side. You are done in two minutes. In the trades, we call it a story pole. it is use for repeated measuring work. It is a lot more accurate then a tape. Save you some money by buying tools.

If you do not have a stick long enough, get two stick and screw them together and make em' long enough for the job.

Jeff

Get someone to help you and put some tension on the retractable tape.... 12 feet should not be a problem.

I'm guessing you are serious about your sound quality if you need that kind of accuracy.... (but you did say "about" 12 feet...)

Or take a piece of string 12' long, pin to wall, pull straight, mark ceiling, repeat.

Dude.
Lay it out on the ground with masking tape and use a plumb bob to transfer it in the UP direction ;)

This!

Saw a guy build a floating circular stair case this way.

:d

the stick is the way to go.

you can buy laser tapes and they are awesome, but more for measuring something that already exists, not for laying out new work.

Would have enjoyed seeing that!

String.

Back in the olden days they built most everything with a compass, a straight edge, a level and a plumb bob.
Kind of a lost art.

I used to be a millwright and most millwrigths had no idea where than name came from. I researched it and was facinated by what I found.

Many moons ago before the industrial revolution, lots of machinery was built out of wood. Things like wind mills, grain mills, etc.
Carpenters were great at woodworknig but not as strong at the mechanical part so a specilized craft emerged of mechanics who worked in wood. sdopme of the stuff they built was incredible and they did it with wood working tools and basic geometry.

totally doable with a tape, and helper.

Are some of you guys serious? It sounds like a typical bunch of guys all right. Why make thing so complex while a simple stick with a mark would do the trick. I don't think he has any help, so the tape sags. Plumb bob, tape on the floor, hole in the wall to hold a string is a huge waste of time. Mark the holes and cut the ceiling already. I would have mark the holes to within 1/16" by the time I finish typing this. I type really slow.

^^^^ Isn't that the staircase that "Jesus" built in Santa Fe?

As stated above, I would not trust the laser tapes for laying down construction. They are best for measuring a room for its dimensions for estimation of flooring materials etc.

Simple tools are best. The stick or string is the way to go. Just like a water/tubing level is best for repeated leveling in various places, although those laser spinning levels are great for suspended ceilings and the like.

I have one of those Swiss made laser measuring device. it is very accurate. But not always practical for daily use. A small stick or tape measure is still use very often. Roto laser levers are great. I even use it to set up plugs in our kitchen remodels. Nothing like having a slight out of place plug in a finish kitchen. It reads up against a tile backsplash.

Brand?

pls