Film-Tech Forum ARCHIVE: Christie Vive Audio

This is topic Christie Vive Audio in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Tim Asten (Member # 4051) on 07-19-2013, 07:33 PM:

It seems Christie are now jumping on the sound system bandwagon, using ribbon speaker technology. Christie Vive Audio

Posted by Louis Bornwasser (Member # 3063) on 07-19-2013, 08:25 PM:

From the same folks that gave us. . . . Megasound! Louis

Posted by Steve Guttag (Member # 268) on 07-19-2013, 09:30 PM:

And Sound-A-Around. http://www.film-tech.com/warehouse/wareview.php?id=543&category=2 and Xenosound (Courtesy of Kelmar).

Posted by Richard Fowler (Member # 893) on 07-20-2013, 08:50 AM:

Did a couple of Sound a Round installs....my boss at the time sold it to the theater owner based on the "pretty" paint job and displays.

Posted by System Notices (Member # 2357) on 12-26-2016, 04:12 PM:

It has been 1255 days since the last post.

Posted by Marin Zorica (Member # 1716) on 12-26-2016, 04:12 PM:

I would get back alive this post. I set up cinema using Vive audio speakers from Christie, combination was LA4+S215 for screen channels, S218 for subs and LA4S for surrounds. All went bi-amp true datasat AP20 processor......first i listen to it with all eq to 0 and was relly suprised how it is sounds good, after doing eq some time aligment et it did sound even more natural to me.....after doing much standard JBL, KCS this was a two step above it!

Does anybody else did set up, or listen to any vive audio combination, so would like to hear impressions.....

Posted by Steve Guttag (Member # 268) on 12-26-2016, 04:25 PM:

I think it has replaced the dreaded EV DH1A driver as the single most painful sound equipment I've ever listened to. It absolutely ruined an Atmos demonstration for me.

But I'm glad you liked it.

Posted by Louis Bornwasser (Member # 3063) on 12-27-2016, 09:58 AM:

Thank you Steve. Especially for the EV comment.

Posted by Marin Zorica (Member # 1716) on 12-27-2016, 11:41 AM:

Hmmmhmmmm.....did not heard EV in cinema here, but all jbl cinema instalations sound like Steve described for ev. Anyway, a colegue was with me and we were in cinema opening watched rogue one. Since he js fan, he watched it week before at local imax and told me this wasequaly good. For me, most most positive thing is that dialogue was clear and not distorted in higher levels, specialy when mixed with movie background noise.

Posted by Steve Guttag (Member # 268) on 12-27-2016, 12:11 PM:

Give a QSC SC-424 or SC-423 a try. The phrase night and day come to mind.

Posted by Mark Gulbrandsen (Member # 72) on 12-27-2016, 01:10 PM:

I'll second using those QSC's.... I have a number of those out in the field and they are nothing short of phenomenal.

The Christies use ribbons for MF-HF which by their own nature are very inefficient and highly directional. They try to alleviate that directional by placing them in an arced configuration. LOL! The screen loss must be tremendous!

Christie's sole use of Class D amplifiers is also very bogus. I have quite a bit of experience with Class D going all the way back to the Infinity Class D amp of the 1970's and the only real benefit is the efficiency of it. Class D can not put out any peak power levels at all past it's actual rating, so you need to purchase a lot larger amplifier than you would normally need or you will not be able to properly deal with Digital Audios very high peak levels. Just like in cinema processors, when you hit that maximum level it's the same as hitting a brick wall.

Mark

Posted by Jay Wyatt (Member # 8768) on 12-28-2016, 12:18 AM:

quote: Mark Gulbrandsen
Class D can not put out any peak power levels at all past it's actual rating, so you need to purchase a lot larger amplifier than you would normally need or you will not be able to properly deal with Digital Audios very high peak levels.

I'm no expert in amp topology, do you mind elaborating on that?

At least with the material I've seen from QSC on the DPA amps (class D) they claim to have improved peak output compared to the DCA line (class AB and H). Source

I'm not sure if this also applies to the Christie CDA amps or not. They appear to be OEM'd Crest(Peavey) Pro-LITE series amps based on the specs and similar front panels.

Posted by Mark Gulbrandsen (Member # 72) on 12-28-2016, 12:01 PM:

All digital circuits in sound processors, recorders, amplifiers etc have a 100% maximum level they can achieve before you hit the veritable "brick wall level" after which you typically have nothing but lots of distortion. Digital amplifiers are much the same as any other digital circuit in that they can only achieve an absolute maximum power output level period because the switching devices operate fully on or fully off and generally at the rail voltages. You get around this by installing much larger sized amplifier than you might have otherwise needed in order to accommodate the peak levels. Digital amplifiers also have to employ output filters and these filters if poorly designed affect the high frequency and can create phase shift, delay and other nasty artifacts. The advantages to them are they can be very efficient, lightweight, and have almost no heat output... but generally all at the expense of sound quality.

The DCA is not a digital amplifier. It only utilizes a switching power supply and it still offers a peak ability above a true digital amplifiers "brick wall" because of the storage it has in it's power supply capacitors.

There are places for digital amplifiers for sure, I just don't think the cinema is the place. Air Force helicopters have had them since the late 1960's for the on board PA's and one of those was the basis for the design of the original Infinity digital amplifier around 1974!

Jay: This paper gets into detail of how a Class D amplifier works... [url= http://www.eetimes.com/document.asp?doc_id=1274757]http://www.eetimes.com/document.asp?doc_id=1274757[/url]

Mark