Homebrewed Music

I’ve been using my Panasonic Lumix GH3 as my main video cam for the last year or so and it’s a terrific tool. The articulated display, live HDMI out, high bitrate codecs, WIFI connectivity, and luscious image quality have made it my favorite shooter. But I’ve avoided using camera audio even though the GH3 does have some intriguing audio features. There’s a mic input backed up with a 19 step Mic Level adjustment in the video menu, as well as a rough level meter and a headphone jack for monitoring. But in my initial tests I thought the audio recorded in the camera was not up to par, so I continued with my usual procedure of recording audio on a separate dedicated recorder.

Some internet posters, though, reported that they were using the GH3 mic input and getting good results. They recommended setting the GH3 Mic Level adjustment to 1 then providing a fairly strong, but still mic level, signal. I was persuaded to do some more testing and just in the nick of time Zoom released a firmware update for the H6 that adds the ability to adjust the level of the line out signal. The line out level is -10 dBu, or consumer level. The new firmware gives the ability to attenuate the output in 5 dB steps down to -30 dB.

With a little experimenting I found that a setting of -25 dB on the Zoom line level adjustment along with a setting of 1 on the GH3 Mic Level gave me clean audio in the GH3 without clipping or activating a limiter in the camera. Even better, the recording in the camera was very close in level to the recording captured in the Zoom H6, so I could use this setup and simply aim for a good reading on the Zoom H6 meters while being confident that the GH3 was getting the right input level.

I created a video with a bit of narration and some slack key guitar, with a couple of sections repeated with the audio from the GH3 followed by the same audio from the Zoom H6. I used the 50 Mbps MOV format with PCM audio, presumably the best the camera can produce.

But of course YouTube is not the ideal source for audio comparisons, so I’ve created clips for you to download and compare in a more controlled way. This is the same audio that was used in the video above, and it has received the same treatment, which consisted only of adjusting the level based on a test tone recorded to both sources. I compared the test tones from the two sources and found the Zoom H6 to be 1.37 dB lower in level than the GH3 track. So I used the adjustment feature in the Sonalksis FreeG plugin to add that 1.37 dB to the Zoom track. Small level differences like this can really throw off a comparison of clips that are otherwise the same, so I nearly always take some steps to match levels in these tests.

These files are uncompress 44.1/16 WAV files, so they will not stream well. Ideally you should download them and use an ABX comparator so you can listen to the clips in a double blind comparison.

Narration-GH3
Narration-H6
Music-GH3
Music-H6

When I listen to these clips, especially the quiet sections at the end of each clip, I hear a bit more noise from the GH3 recordings. With that said, the audio seems to me to be better than other video cameras I’ve used, and I expect to use the mic input on my GH3 for some future projects. Hopefully this comparison will help you decide if it will work for you.