Film-Tech Forum ARCHIVE: Disable Matrix Decoding on NSYNC / AUX

This is topic Disable Matrix Decoding on NSYNC / AUX - USL JSD80 in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Sascha F. Roll (Member # 9043) on 05-17-2019, 01:28 PM:

Hi there,

is there any way to disable the Matrix Decoding Function that is by default enabled on Nonsync/Aux Inputs (Analog and SPDIF)?

All the Best
Sascha

Posted by Marcel Birgelen (Member # 6801) on 05-17-2019, 02:15 PM:

I guess it depends on the decoder.

But afaik, the default for the Nonsync input on the CP-650 and CP-750 is Format 60, which AFAIK is L/R without Subwoofer and doesn't do any matrix decoding.

This is the full table:

Format 60: Nonsnyc
Format 61: Nonsync w/ SW
Format 70: Mono C w/ SW
Format 71: Mono C
Format 73: ProLogic LCR
Format 74: ProLogic (w/o SW)
Format 75: ProLogic w/ SW

PS: Didn't read the subject apparently. Don't have sufficient experience with the JSD-80 to comment on it. But I do remember a drop-down option in the client software, where you could specify the type of matrix-decoding. [Wink]

Posted by Carsten Kurz (Member # 5396) on 05-17-2019, 03:04 PM:

Hard to believe there is no option to disable matrix decoding on NS/AUX inputs. I know there were a few discussions on matrix decoding with the JSD80, but I can't see anything in the manual suggesting it is possible at all?

The JSD80 brochure though seems to suggest it is possible, and may not be disabled at all:

'Two S/PDIF inputs with Dolby® AC3 or ProLogic on RCA jacks'
'Two non-sync stereo inputs with surround decoding on RCA jacks'

Clueless, without access to a model on current software and with the latest config GUI...maybe Harold can help...

- Carsten

Posted by Harold Hallikainen (Member # 5405) on 05-17-2019, 05:50 PM:

I don't remember the JSD-80 very well, and I'm at the Dayton Hamvention without a Windows computer, so I can't look at the GUI. the GUI is, however, available at http://ftp.uslinc.com/Products/JSD-80/Software/GUI/ .

Harold

Posted by Marcel Birgelen (Member # 6801) on 05-17-2019, 09:57 PM:

http://www.film-tech.com/warehouse/manuals/USL-JSD-80.pdf

Page 33: 10.5 Format Options

Isn't that what you're looking for?

Posted by Gordon McLeod (Member # 33) on 05-17-2019, 11:16 PM:

No you cannot disable the matrix on either nonsync or aux to the best of my knowledge

Posted by Carsten Kurz (Member # 5396) on 05-18-2019, 05:36 AM:

The only thing I remember is that there are some options to configure the matrix decoding for film formats, but I think there are no such options for NonSync and Aux. Sascha is familiar with the Setup Software, and while the manual doesn't show screenshots of format options for NonSync and Aux, I am sure Sascha would have found them. Weird if it actually can't be disabled. From my experience, matrix decoding may give pleasing results with some material, but can have strange effects on other signals. And sometimes you simply don't want that to happen. I recently had to play a video where matrix decoding lead to near full extinction of dialog. While that certainly was a fault in the audio track, I was lucky I could disable matrix decoding on our AP20 for that presentation.

- Carsten

Posted by Sascha F. Roll (Member # 9043) on 05-18-2019, 10:00 AM:

Thanks for your input! I have the latest Laptop GUI and Firmware on the JSD80 itself, there is no option to disable Matrix Decoding there.

I was hoping there is a semi-hidden way to disable, Dip Switch on the Board or similiar...

Best
Sascha

PS: The problem became evident last night at our open air cinema: Q&A in front of the screen (speaker), Rackmixer fed into the analog Nonsync --> Mic signal on Center channel, which of course didn't work with the people standing directly in front of the Center speaker. I temporarily fixed that with feeding the rackmixer into the L /R input on the DB25 8 channel analog input which is usually occupied by the DA20 / DTS. (Yes we're also playing 35mm at our open air...)

Posted by Gordon McLeod (Member # 33) on 05-18-2019, 01:54 PM:

If your mic mixer has a mic level output feed it into the JSD80 mic input which can be set to surround only