Film-Tech Forum ARCHIVE: Cue Blip -- is there a standard

This is topic Cue Blip -- is there a standard in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=008245

Posted by Frank Angel (Member # 248) on 09-11-2006, 06:50 PM:

I have done some studio work and there has always been either a mag reel full of them or they were on RTR audio tape; these days they are just files in the computer. Point is, they were always there when I needed them. Recently a hard drive crashed and that file is going. I tried to hunt down the continuous RTR that we had of it -- enough I thought that would last a lifetime, but it was nowhere to be found so I had to make them "from scratch" and wind up with a reasonable facsimile.

Thing is, having to do this, now I realize that I really don't know much about them. I assume that they are placed to coincide with #3 in the Academy countdown. I always thought these were just kind of a given, and if I had to hazard a guess, I figure maybe 1/5th of a second....maybe a 1000hz tone? In fact, when we were making audio masters, we had a full 10-1/2in open erel of cues in stereo on 1/4in tape. There was just a continuous sine wave on both channels in stereo; one channel was probably a 1500hz tone, and maybe a 750hz on the other. We would just slice about 1/4in of it and splice it in the timing leader. It wasn't any more accurate or scientific than that. And we certainly didn't have any specific info about them

So here's the question. Is there a standard for these cue blips? I always assumed they are always in sync with #3, but where are they when it's an SMPTE Universal leader? #2? And how long in duration are they supposed to be? What's the correct frequency of these blip? Is any of this specified?

When we needed our blips, we would simply cut a sliver from the mag reel marked "cue tape" -- no spec, just cut enuf so that it sounded like what you hear if you let the leader play. For us, the only specification was that you would have to cut the sliver so it sounded the same to our ears as authentic blips on theatrical prints and that it was in sync with #3.

Anyone know any more about these pesky little buggers?

Posted by Scott Norwood (Member # 30) on 09-11-2006, 07:15 PM:

It's supposed to be one frame in length. Christy's Editorial sells adhesive-backed magnetic strips (simply called "sync pops") with the cue tone recored on them. They are quite inexpensive. You can cut them to length and stick them on 16mm or 35mm mag film or 1/4" recording tape. Obviously, the frequency will be different depending on the speed of the tape or mag film. I don't know if there is a standard frequency, but I would assume that it should be 1kHz. It should correspond with the "3" on Academy leader or the "2" on SMPTE leader.

If you need a reel of 1kHz tone on 1/4" tape, let me know the tape speed and I'll send you some (half-track stereo only).

Posted by Wayne Keyser (Member # 2420) on 09-11-2006, 11:22 PM:

For what it's worth, there's an online digital filmmaker's resource site called "2-pop" (jargon for the audio blip at '2' on the SMPTE leader).

http://www.2-pop.com/

Posted by Frank Angel (Member # 248) on 09-12-2006, 10:38 AM:

Hey Scott...thank's for the offer. But I can easily make as much as I want in the studio -- the stereo version that we have been using works just fine, with two different tones on each track...makes a nice and actually quite distinctive pop. I was just wondering if it was ever stanardized.

And Wayne, thanks for the URL.

Posted by Jeffry L. Johnson (Member # 453) on 09-12-2006, 11:47 AM:

SMPTE RP 25

Audio and Picture Synchronization on Motion-Picture Film Relative to the Universal Leader for Magnetic and Photographic Records