Film-Tech Forum ARCHIVE: Imax "laser aligned" sound

This is topic Imax "laser aligned" sound in forum Large Format Forum at Film-Tech Forum ARCHIVE.

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Posted by Marco Giustini (Member # 4544) on 01-07-2010, 05:24 PM:

On Imax website I read that Imax delivers "laser-aligned digital sound that envelops you".

What does it mean? Is it a Marketing nonsense or does it mean something?

Cheers

Posted by Jonathan Althaus (Member # 5042) on 01-07-2010, 06:45 PM:

Isn't all digital sound "laser aligned"? Sounds like marketing fluff to me.

Posted by Adam Martin (Member # 641) on 01-07-2010, 09:47 PM:

A laser is attached to the speaker cabinet and used to aim the speaker at a specific spot in the auditorium.

Posted by Chris Aulisio (Member # 5523) on 01-07-2010, 10:25 PM:

The why does IMAX still use the Microphones to set sound??

Adam, if you still have my number from Century Days call me. I can not PM you, I'm too new

Posted by Adam Martin (Member # 641) on 01-07-2010, 10:35 PM:

The laser is related to speaker coverage and the microphone is related to EQ.

Posted by Bobby Henderson (Member # 840) on 01-07-2010, 11:00 PM:

"Laser aligned."

Yeah, when I play a CD in a CD player it plays "laser aligned" audio! Haw haw.
[Roll Eyes]

Posted by Marco Giustini (Member # 4544) on 01-08-2010, 06:02 AM:

I see. And does it make such a big difference to advertise it as the only feature about its sound system?

Posted by Mark J. Marshall (Member # 1409) on 01-08-2010, 06:31 AM:

Our engineer at AMC told me back in 1992 that the speakers in their large auditoriums were aligned using a laser.

Posted by Gordon McLeod (Member # 33) on 01-08-2010, 09:18 AM:

For years we have used a laser that replaces the HF driver to aim horns in theatres

Posted by Louis Bornwasser (Member # 3063) on 01-08-2010, 12:38 PM:

Funny! I use my EARS!

Everything else (mikes, EQ, multiplexers) is only used for confirmation. Ears first and last; instrumentation in the middle. Louis

Posted by Mike Blakesley (Member # 26) on 01-09-2010, 09:21 AM:

"Laser" is like "digital;" it has a high-tech sound to it so people assume it means higher quality.

Posted by Mark Gulbrandsen (Member # 72) on 01-09-2010, 11:21 AM:

I'm with Gord. I've had an adaptor that I use with my Alignotron and mount it to the back of the horns.

Louis.,.. you can't tell by ear where two feet above the rear center seat is at... What does it sound like at three feet and four feet above that same seat commpared to two feet ?

And what about the seats on each side... What does that sound like?

Mark

Posted by Jake Spell (Member # 5294) on 01-09-2010, 05:56 PM:

I agree with Louis, sound sytems need to pass the hearing test, they must SOUND good, not just look good on paper, well computer screen.

Posted by Louis Bornwasser (Member # 3063) on 01-09-2010, 07:27 PM:

#1 I walk around to sample various areas.

#2 If I am trying to keep audio off the rear wall, I put the mike there and put the Abacus in the speaker loft with me. Aiming is easy.

At the National in Washington DC, it was necessary to stack 4675 horns on each channel. It was decided to cover the main floor with the lower horns and the 3 balconies with the upper horns. The point of interference was put on the front of the first balcony. Put a mike there, airm the lower horn, kill the audio to it and then aim the upper horn, then reconnect both. Job done! Louis

Posted by Joe Redifer (Member # 3) on 01-09-2010, 07:33 PM:

Anyone who EQs by the numbers and walks away without listening to good known material is a poor sound technician.

Posted by Mark Gulbrandsen (Member # 72) on 01-09-2010, 09:02 PM:

Joe, Thats true but thats also not what we're discussng here...

Posted by Dave Callaghan (Member # 1544) on 01-12-2010, 01:35 AM:

This conversation is somewhat surprising.

Listening of course but calibration surely also plays a role.

Eyeball estimates are fine when you have nothing else to go by, but why not use available tools to improve and refine the result?

I don't believe I'm the only person to hear differences in pink noise reproduction from the FOH channels.

Would anyone work without the 35PA SMPTE loop for picture determination?

Trusting your senses is well and good but why not use tools to assist us?

What is amiss with using available technology - e.g. laser pointers - to accurately align the "on axis" response of speaker drivers of a multiple source array?

Frankly, how else to do it when the floors aren't level and the walls aren't vertical in the real world I am familiar with? Just what reference is anyone expected to use in the case of a house without a balcony?

I appreciate such techniques could work in such a circumstance as Louis has mentioned, but the original topic is concerned with an IMAX claim and I am not aware of any IMAX balcony houses.

This is one case where the advertising does pay dividends - providing the lasers are actually used to assist with the alignment.

We all just have to trust them to be honest and the lasers were actually used.

As an IMAX projectionist, I can confirm the service from IMAX is genuine, the machines are serious and their attention should be the norm instead of the exception we often find in today's exhibition industry.

And if there are any IMAX balcony houses, I do stand to be corrected on that point.

Posted by Marco Giustini (Member # 4544) on 01-12-2010, 06:22 PM:

I'm not saying that aligning speakers by laser is wrong, just that maybe it's nothing so important to quote on imax.com - or at least not as the only and main feature of Imax Sound Systems [Smile]

Posted by Randy Stankey (Member # 64) on 01-14-2010, 03:15 PM:

I have laser sights on some of my guns but they don't mean shit if you can't shoot straight.

Sure, a laser is a nice, convenient way to sight a gun but a poor marksman couldn't hit the broad side of a barn regardless of the sight he uses.

A poor sound technician couldn't make a theater sound any better whether he uses a laser or just eyeballs the speakers into place.

When I was installing speakers we simply had somebody sit in a seat at the proper location in the theater while holding a flashlight, pointing it at the speaker. The installer looked down the throat of the horn just like looking down a gunsight and aligned the speaker that way.

Maybe next time I'll go get a laser pointer and a roll of gaff tape so I can have "laser aligned" speakers too! [Big Grin]

Posted by Richard Hamilton (Member # 321) on 01-14-2010, 04:40 PM:

quote: Mark Gulbrandsen
Louis.,.. you can't tell by ear where two feet above the rear center seat is at... What does it sound like at three feet and four feet above that same seat commpared to two feet ?

And what about the seats on each side... What does that sound like?

Mark, You use the laser to aim the speakers dead center where the main seat is. That is the best seat in the house "screw everyone else" [Razz]

. When I see a movie, I usually move around until I find that sweet spot [thumbsup]

, everything else is just muffled and you can't understand the dialogue.

By the way, Imax sucks

Posted by Mark Gulbrandsen (Member # 72) on 01-14-2010, 09:46 PM:

Richard,
THX doesn't always do it that way... Exactly where you aim the horn is also dependent on speaker model, sloped or stadium, and the size of the room
!!

Posted by Jonathan Althaus (Member # 5042) on 01-14-2010, 09:59 PM:

quote: Richard Hamilton
Imax sucks

I agree. I really don't like the Imax theatre in Dallas, and their Avatar presentation was horrendous and just didnt't sound right.

Posted by Adam Martin (Member # 641) on 01-15-2010, 12:46 AM:

That's not the fault of Imax, that's the fault of the operator.

Posted by Richard Hamilton (Member # 321) on 01-15-2010, 08:19 AM:

Mark, you know me, I was being a smartass [Big Grin]

Adam, I have yet to be in an Imax theater that has impressed me [Roll Eyes]

Posted by Louis Bornwasser (Member # 3063) on 01-15-2010, 11:41 AM:

Air & Space Museum in Washington D.C. always looked good!

Laser aligned speakers: Advertising hockum, razz ma tazz, hockum, etc. Louis

Posted by Julio Roberto (Member # 4976) on 01-15-2010, 12:55 PM:

I just hanged a couple of laser-aligned pictures on the wall this Xmas.

[beer]

Posted by Jake Spell (Member # 5294) on 01-15-2010, 10:22 PM:

IMAX done right, where the operators dont mess with the EQ's and actually care to give a good quality preference is amazing, however it seems that everyone thinks that volume knob needs to be all the way up. And those EQ's need some fiddling, and dont forget that the film needs grease from the fingers and dust off the floor to work right...

Posted by System Notices (Member # 2357) on 06-12-2011, 12:12 AM:

It has been 512 days since the last post.