This is topic Hookup Sound from RCA jacks to Dolby CP 65 in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Mike Markwood (Member # 1853) on 08-25-2003, 12:02 PM:
I need to hookup sound from a Satellite Receiver (2-RCA Jacks for output) to a Dolby CP65. Any suggestions on the best way to do this? All I've been able to get so far is sound out of the center stage speaker and I'd like to get more than that.
Posted by Aaron Sisemore (Member # 145) on 08-25-2003, 12:41 PM:
Simply connect the L/R outputs of the satellite box to the L/R non-sync inputs, and set the jumper on one of the cards (I cannot remember which one (card or jumper) right now) to allow surround in non-sync mode and this should give you L/R/S mode (In pre-CP500 Dolby processors, non-sync never was routed to the center channel via matrixing) without having to deal with padding down the sat box (to connect it to the proj 2 solar cell inputs).
-Aaron
Posted by Pete Naples (Member # 761) on 08-25-2003, 02:43 PM:
On the CP65 it is possible to set the non-sync mode to be fully matrix decoded, is it not? There's a jumper on the Cat443 for this.
Certainly on the CP50 and CP55 it's not possible, but there are ways, especially easy if you have an SRA5 installed....
Posted by Steve Guttag (Member # 268) on 08-25-2003, 07:51 PM:
There are always...ways...even on the CP-50 and CP-55...but on the CP-65 a 2:4 decode is available right out of the box as others have described...set the jumper on the Cat. 443
Steve
Posted by Duncan Smith (Member # 1556) on 08-28-2003, 08:22 AM:
Yeah Steve, that's totally true. I get L,C,R,S and sub from my non-sync on my CP65 and I'm reliably informed it can be done with a CP55 and SRA5 too (not sure about the sub but I don't see why not).
Dunk. ![[thumbsup]](graemlins/thumbsup.gif)
Posted by Pete Naples (Member # 761) on 08-28-2003, 01:11 PM:
Indeed it can be done on a 50 or 55 with or without an SRA5, having an SRA5 just makes it a little neater imho.
One thing though, I often come across CP45, 65's, 500 and 650's where the operator has decided that non-sync should be pro-logic decoded. IMHO unless the non-sync source is ENcoded it sounds cack. With most of the pop music drivel they play being essentially two channel mono, or joint stereo all that really happens is most of the signal gets shoved out of the centre, with the surrounds shh shh'ing and sub going woobawoob. I much prefer to have a stereo non-sync source (CD player) in stereo, with the surrounds off. Keep the pro-logic decoding for pro-logic sources!
Posted by Josh Jones (Member # 447) on 08-29-2003, 12:03 AM:
Its easy to get a cp-55 to decode center. Just snip one diode on the cat 243. Sub on the other hand, is a bit more of a trick.
Josh
Posted by Brian Guckian (Member # 1678) on 08-30-2003, 12:34 PM:
Greetings Pete;
One thing I've never quite understood is how matrix decoding can extract unintended surround information. Is it because the phase shift used to encode surround can sometimes occur "naturally" in a L-R pair so to speak? I more easily get how frequencies can be re-directed to the sub(s) via OBE, etc.
Also presumably you can set up the different non-sync progs in the CP500 and CP650 so you can have one with matrix decoding and one without. But what about the CP65 and earlier? Are there any mods to switch between say CDs that are just L-R and the newer CDs which are Dolby encoded?
Cheers!
Posted by Mike Markwood (Member # 1853) on 09-04-2003, 05:46 PM:
I set the jumper (J2) on the CAT. No. 443 for Surround.
I've tried J4 with both STD and 2:4 and all I get sound out of is my center screen speaker.
Anybody have any ideas?
Posted by Gordon McLeod (Member # 33) on 09-04-2003, 07:36 PM:
Is it possible you have a mono nonsync feed? If so the decoder would give you only centre channel
Posted by Brian Guckian (Member # 1678) on 09-05-2003, 11:07 AM:
Mike, what signal present LEDs are illuminating on the Cat. 242 when you're running the satellite feed?
I had this problem a few years ago with a cable TV decoder going into the CP65. In that case, though the decoder box was clearly fitted with L-R output phonos, the output was actually in mono.
This was to do with how the cable feed was connected into the decoder in the first place (via an RF input). In the end, we had to run the feed via a stereo VCR and then into the decoder, whereupon we got proper LCRS.
The actual source could be mono, but surely all satellite stations must broadcast in stereo / Dolby Surround.
Do you have any Dolby Surround-encoded CDs? That would show up if the problem is in the Non-sync 2:4 decoding, though it seems unlikely. It's sounds like the problem is with the decoder.
Hope this helps.
Posted by Jean-Michel Grin (Member # 1360) on 09-05-2003, 06:15 PM:
A tip just in case:
Add a audio ground separating transformer between the satelite reciver ant Your Dolby processor to suppress hum and ground loops.
An alternative to the expensive Di-Boxes is to use an audio transformer such as used in car audio installations.
I've used a bactch in some multiplexes and i'ts sound well, and nobody will note an alteration of the Non-sync audio signal...
Bye,
Posted by System Notices (Member # 2357) on 10-05-2007, 05:26 PM:
It has been 1490 days since the last post.
Posted by Lyle Romer (Member # 1266) on 10-05-2007, 05:26 PM: