This is topic Need help to mount QSC ISA amplifiers with a cp55 in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.


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Posted by Elia Orselli (Member # 4673) on 03-14-2009, 08:50 AM:
 
I bought two QSC ISA 450 to replace 4 old Cinemeccanica C300 amplifiers and I have three problems to solve:
1. What connector is better? XLR or terminal block?
2. What low frequency filter is better? 30 or 70Hz? Speakers are KCS 2000 series ( )
3. ISA450 has 1.07V of imput sensitivity so I have to solder again W5, W6, W7 and W8 jumpers on cat 242 of the cp55. These jumpers now are cut I think because the imput sensitivity of C300s amplifier is more than 1.23V. Do I have to change other elements on the cp (in the manual I downloaded there aren't the last lines of the paragraph about this operation)?

Thanks a lot.
Elia Orselli - Cinema Cappuccini Imola, Italy

[ 03-16-2009, 02:18 AM: Message edited by: Elia Orselli ]
 

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Posted by Samuel Hynds (Member # 2610) on 03-16-2009, 09:40 AM:
 
for your first question - the XLR input or the terminal block would work; just depends on if you want to change the wiring from the CP55 to the amplifiers. You could use a pre-made cable with XLR male connectors & cut the cable to wire to the terminal strip of the CP55.

As for the High pass filters of the ISA - use the 30Hz setting for your stage loudspeakers & the 70Hz for your surrounds. Turn the filter off for your subwoofer.

For the jumpers on the CP55 - it may work - you'll have to turn down the output level for each channel output of the CP55.

Good Luck -

Sam Hynds
Product Specialist - Cinema
QSC Audio Products, LLC
 

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Posted by Elia Orselli (Member # 4673) on 03-16-2009, 12:29 PM:
 
Hi Sam,
Thanks for your complete reply.

quote: Samuel Hynds

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it may work

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