HD Field Recorders for Live Production--UPDATED!

Audio Capabilities and I/O

Audio is where video recording gets complicated. The absence of adequate audio capabilities is an unfortunate oversight and ultimately is why I don’t love any of the available external recorder solutions discussed here. If the audio is embedded in the HD-SDI (or HDMI) signal, then it gets passed along on the same video input cable. Embedding audio in the HD-SDI is usually accomplished by either connecting the sound board XLR output to a connected video camera or--better yet--the video switcher, provided it has audio inputs.

The other audio input option is an analog connection--either XLR or a headphone jack input. I prefer an XLR connection, mainly because it locks in but also because it is a balanced connection. Often I often don’t sit right next to the audio console, so cable length is a consideration as well. Portable recorders lack XLR inputs, mainly for size reasons.

Having the camera operator handle the recording audio levels isn’t the workflow I want to use, especially as I want their ears to be focused on my intercom feed to them and not listening to the program audio from a soundboard. However, in some cases individual camera operators, with their limited VU meters and headphone outputs, are better equipped to handle this monitoring than the video switcher operator if they don’t have the required additional equipment.

Monitoring audio from portable recorders is easy, as most provide a headphone jack, but unfortunately most rackmount units lack a basic headphone jack and rely on audio level displays--some better than others--as their sole audio monitoring tool. This is a major oversight. You need to hear the audio feed to listen for pops, hiss, clicks, interference, dropouts, and noise in general. A VU meter can’t tell you how clean your audio is and needs to be used in tandem with listening to the program audio with a good set of headphones. Unfortunately, some units that have headphone jacks lack a proper VU meter display and rely on small audio level meters. In general, no one external recorder has a headphone jack, video display, and proper VU meters.

Video Mixer Audio

I use my Blackmagic Design ATEM 1 M/E (Figure 5, below) as the primary XLR audio input point from the soundboard. Its software control panel offers me the ability to mix different line level inputs and to embed my audio mix in the HDMI or HD-SDI outputs, as well as provide a pair of XLR audio outputs. The visual audio level monitoring is great but like too many of the recorders, it lacks a headphone output, either from the computer or the video switcher panel.

Figure 5. The Blackmagic Design ATEM 1 M/E switcher

My solution for both the video switcher and external recorder audio and video monitoring is to use a Marshal V-LCD70MD-3G 7” HD monitor (Figure 6, below). I like this specific monitor because it has a high-resolution 1024x600 LED Backlit IPS panel that is way higher resolution than the video monitors on any external recorder. It also has a proper VU meter that I can overlay on the screen and a headphone output that I can use to actually listen to the audio.

Figure 6. The Marshal V-LCD70MD-3G HD monitor

As much as I love my ATEM 1 M/E for its rackmount form factor, price, and versatility, I have to admit I also love the VU meters and headphone output on the Sony MCS8M video and audio mixing switcher.

Recording Options

If you use a video camera with a clean, high signal-to-noise ratio output, you don’t always need an extremely high-bitrate uncompressed or intrafame codec recording. Some users will appreciate high-bitrate features but recording the archive from a corporate webcast or a conference doesn’t normally warrant the extra initial effort, higher-specification recording media, and storage cost. I prefer to use recorders with a 100Mbps recording option of ProRes LT, which is already 4x larger than what my camera can record internally. By comparison, ProRes HQ is a 250Mbps codec and overkill for all of the live non-greenscreen work that I do. Avid users will appreciate recorders that offer DNxHD recording options.

In addition to requiring more storage space, more time to transfer, and faster hard drive RAIDs for video editing, higher-bitrate codecs require faster and more expensive recording media. Some of this is only a factor of spending a bit more money on a more powerful video editing workstation, but if you are a client and you want to watch the footage on your laptop, you will appreciate a bitrate that doesn’t exceed what your laptop hard drive can power.