my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Digital Cinema Forum   » AES DB-25 switcher

Author Topic: AES DB-25 switcher James Larden Film Handler Posts: 14 From: Montreal, QC, CA Registered: Jan 2010 posted 02-08-2010 03:09 PM                        Hello, We're currently looking to acquire d-cinema capability in two of our cinemas. If we install a DMA8+ does anyone know if there is an available switcher so that we can share the DB-25 input; to switch from the AES output of a d-cinema server to the disembedded AES audio from HD-SDI sources such as HDCAM. Thanks  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 02-08-2010 05:19 PM                     Got money? The SDI audio de-embedding is simple. http://www.blackmagic-design.com/products/miniconverters/. Black Magic Design makes some of the best SDI converters I've ever dealt with. The SDI to Audio will output it in AES3 (balanced) so it will be ready for the DMA8 (once you make your TRS to DB 25 cable). As for switchers...now you are into some money. There are AES switchers...they are typically expensive and often 4x1 and and $500-$700 a pop. You can go the cheap route and just get a DB25 A/B switch and pray that the digital integrity will not be too compromised going through it (AES3 is based on a 110-Ohm impedence...a cheap passive A/B switch will have single conductor wires inside). You could build a patch bay of your own with DB25 connectors...experience has shown though, that Dsubs do not fare well with many repeated plugs/unplugs (particularly male plugs). You could put in an AES rated patch bay...again, not cheap. But lets look at this a bit...on your HDCAM...since you are looking to de-embed...I'm thinking you have a JH3 or similar deck. 95% of all HDCAM tapes are 2-channel...the other 5% have something funky on the 3/4 tracks like Dolby E. Why not save yourself a lot of grief and money...let the DCinema keep the Digital 1 to itself and let Digital 2 or three work with the HDCAM...if you need the Dolby-E track on 3/4 (if it exists) then move the TRS plug on the de-embedder over...pretty simple and you've spent far less money. Steve  |  IP: Logged James Larden Film Handler Posts: 14 From: Montreal, QC, CA Registered: Jan 2010 posted 02-09-2010 11:33 AM                        Much obliged, I already discarded the DB-25 A/B switcher solution for the reasons you listed. If cost was no object could one install a cat.790 card into a CP-650 while using a DMA8+ as well, thus having two balanced AES DB-25 inputs?  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 02-09-2010 12:59 PM                     bzzzt...the Cat 790 uses unbalanced inputs. You could use a converter to make them balanced (either in-line transformers or the Odyssey products 650-OPTIO-AES) The Cat 778 uses balanced inputs...BUT it kills your analog outputs so you only have AES outputs too.  |  IP: Logged

All times are Central (GMT -6:00)

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.