Audio Balancing Act
I had no problems recording with any of several software tools, including Vegas Audio, Windows Sound Recorder, and the Winnov Capture utility.For the first audio test — to test a balanced source — I recorded with a studio microphone (AT4060), and the captured result sounded so fantastic that I thought perhaps the high quality was attributable to the tube pre-amp, the limiter/compressor, and our new studio. For the second audio test, I connected the audio-out from a low-end consumer VCR, through an unbalanced-to-balanced transformer, directly into the Broadcaster without any signal enhancement. While not as good as the results of the first test, the sound was surprisingly clear and full. I was impressed.
The audio outputs worked fine, but remember that just like the inputs, these are balanced only, not balanced and/or unbalanced. If you try to output to powered PC speakers you will fail, unless you convert the signal from balanced to unbalanced before going to the speakers. It won’t hurt anything, but sound will be barely audible at best.
Pretty Pictures
Video encoding went very smoothly overall. I saw no dropped frames, glitches, or other artifacts and the video quality was very good on all tests.
However, I hit a wall when recording at a high resolution of 640x480. Capturing into Windows Media Encoder at 30fps with a key frame every 3 seconds (on our Pentium III 933MHz test machine, with 512MB RAM and a SCSI disk subsystem), the video encoded with no dropped frames. But there was a slight delay — video ran just a fraction of a second ahead of the audio. The delay was more pronounced when I used the Winnov capture utility to gather 640x480 data at 30fps uncompressed. CPU usage, as measured by the Performance Monitor, was pegged at 100 percent during the entire process, in both cases.
When I used Winnov Capture and Winnov’s hardware compression, 640x480 at 30fps took up only 70 percent of the CPU and the video had no speech delay, but this requires use of a proprietary Winnov codec for viewing/encoding the movie.
When encoding in WME at a smaller size of 320x240 at 30fps, with a key frame every 4 seconds, the synching problem did not occur, and the process required much less CPU usage, never rising above 66 percent. This is consistent with Winnov’s claim that the synching problem occurs only when processor-constrained, and that if I wanted to do such high-resolution capture, I’d need more CPU power.
It is also worth noting that downscaling and cropping can be done on-board, avoiding unnecessary bus data transfers as well as reducing an encoder’s CPU resource requirements. So the 320x240 test above, benefited not only from the smaller encoding size, but also from the fact that less data passed over the system bus and to the encoder. Deinterlacing and inverse telecine still need to be handled by your encoder, though.
Who Are You?
At a list price of $899, the Videum II Broadcaster brings great capture capabilities at a good price, but it’s not for everyone. Folks with consumer equipment only, will want to look at simpler products such as Winnov’s Videum A/V or the Osprey 100 (both under $200 on the street). Also, Linux users will find driver support for other Winnov boards, but not this one (NT/2000 only). And DV camera owners will have no use for this solution, as there is no digital video input.
But just about everyone else looking for analog A/V capture should consider this board. It’s a workhorse designed for professionals with a lot of pulling to do. It comes with a large suite of utilities, the video is very good, the audio is outstanding, and it is well suited for the broadcasting professionals for whom it was designed.