Audio

High-quality voice-over with your camcorder microphone

I recently struggled to find a cheap voice-over solution with reasonable quality… My editing software has a voice-over feature which can take sound input from the PC sound card; all sound cards or motherboards have a microphone input; so I just figured I should buy a quality headset with a built-in microphone. The microphone, being closest to the mouth, would bring a beautifully sounding voice while rejecting side noise. Or so I thought — the results were pathetic.

But there is a much better solution, at no additional cost.

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Microphones for PC sound cards have such a low signal, they require overamplification which brings signal-to-noise ratio (SNR) to about 35dB in voice recordings (YMMV). This results in a lot of digital noise contamination with a non-natural voice affected by digital artifacts. This could be due to the insufficient quality of motherboard chipsets naturally, so I replaced this with a full-featured sound card. Little improvement. This might be okay for Internet telephony (VoIP) such as Skype, but totally unacceptable for video productions.

I then found a very nice solution instead using my camcorder microphone for live voice recordings:

  • You need a DV camcorder, or an HDV camcorder configured to record DV.
  • Download and install River Past Audio Capture. The free trial allows for DV/Firewire recordings of up to 2 minutes in a row.
  • Use your camcorder as is, or connect an external microphone — in my case, HDR-FX7E with RØDE Stereo VideoMic. Be sure to remove any tape from the camcorder (to prevent noise from the tape mechanism) and connect it to your PC through Firewire (IEEE1394).
  • Use River Past Audio Capture to record voice-over WAV files, with live audio recording through the Firewire interface. Again, note that with an HDV camcorder this will only work after you have configured the menu to record DV (not HDV).
  • Drop the WAV files onto your editing timeline.

From there, a couple of tips for best quality:

  • You need to speak close to the microphone (I found 10 cm / 3 inches to be adequate).
  • Standard wind protection is most recommended to protect against sounds from breathing at the microphone.
  • Whether you set the camcorder for automatic or manual audio gain is up to you. AUTO guarantees similar audio levels for all recordings, at the expense of some loudness artifacts as you start speaking sometimes (because of the abrupt change in volume, therefore gain). MANUAL will avoid such inconvenience, but you need extra care and control in your voice to avoid audio clipping.

Overall, although professionals might call this a substandard cheapo hack, I found it extremely satisfactory with near-professional quality — more than enough for just any serious hobbyist.