NEP User Review of the 9821: Quality Downconversion and a DA
By Don Phillips - Director of Systems Integration, NEP Supershooters
At NEP, we’ve been using the Cobalt Digital 9821 HD/SD Downconverter since it came out on the market in January 2006. We use it to downconvert HD serial digital (HD-SDI) video to either standard definition serial digital (SDI) or analog composite video. The reclocked outputs feed our truck’s router and production switcher whilst the 9821 also provides downconverted signals to control room monitor wall, repeat monitors and any other piece of equipment that needs to see standard definition video.
Essentially, we use the 9821 everywhere in the input chain of our high definition production trucks.
Versatile High Quality Downconverter
The 9821 offers high quality 10-bit downconversion with quality that allows us to use it for standard definition program distribution. Whenever we are doing a high definition production and there are users who need feeds such as a standard definition clean feed, it is the Cobalt 9821 that we use to downconvert and distribute that clean feed.
The 9821 has four outputs that can be independently configured as either SDI or analog. The four outputs allow us to use the 9821 as a downconverting distribution amplifier and these multiple outputs simplify our systems design.
In addition to its four standard definition outputs, the card offers four other outputs that are reclocked copies of the input to the card. These also come in handy for signal distribution. Plus the 9821 can auto-detect whether an input is HD-SDI or SDI, so in a pinch we’ve used the 9821 as a simple SDI distribution amplifier.
Aspect Ratio Conversion
Aspect Ratio Conversion (ARC) is another valuable feature of the 9821. We utilize the ARC engine to create standard definition letterbox or sidecropped video. For program feeds, we’ll generally take the 16x9 HD signal and crop it to a 4x3 SD signal.
ARC can also be applied to standard definition inputs. The 9821 has the versatility to function as an SDI Aspect Ratio Converter and we’ve used them as such whenever we’ve had a need to meet that requirement.
The ability to perform field alignment upon downconversion of a 720p input is extremely useful. We use this feature when feeding signals to stadium screens. With the 9821 providing proper field alignment we don’t need to feed the signal to a frame sync before it hits the screen switcher that feeds the in-stadium screens.
Highly Reliable
NEP has found the 9821 to be extremely reliable. We use them in a lot of trucks in a lot of places. A TV truck by its nature is a very rough ride. We use only air-ride trailers but it’s still a rough ride with significant bouncing going down the road. The 9821 has proven itself robust; we’ve had no failures.
9821 signal quality is excellent on both distribution and downconversion. It seems to have the ability to recover signals that are near the end of the digital cliff. We’ve had extremely good luck with the 9821’s ability to recover marginal signals.
As for downconversion, we use the 9821 for standard definition program feeds and we’ve seen no degradation beyond normal downconversion artifacts.
openGear is a plus
The fact that the 9821 is designed to work with the openGear frame is another plus. The openGear frame gives us a lot of flexibility. We can easily swap out an HD DA for the 9821 or visa versa. With openGear, cards from different manufacturers and with different functions (SD or HD video processing or audio processing, for example) can be used in any slot in the frame. We don’t need multiple types of frames for different functions.
It used to be that when we had a new technical requirement for a specific production, we’d need to wire in something temporary, or replace an existing frame in order to add modular cards with new or different capabilities. With openGear, we now simply replace a card. It’s a definite hit with the field guys.
With an openGear frame outfitted with a network card we can monitor and remotely control our 9821 cards via TCP/IP. Cobalt plans to add SNMP capability to the 9821 in the near future.
As for service, NEP has a long history with Cobalt Digital and we’ve always been pleased with their response. They’ve bailed us out more than once when we’ve had problems with other manufacturer’s equipment. We’ve found Cobalt’s service and support to be exceptional.
For NEP, the 9821 is an integral part of the video systems architecture that we use on all of our HD trucks.