I haven’t tried this since my camera does have input for external microphone, however, the manual say this:

You record you video with sound on camera. At the same time record the sound separately on a recording device.

Then in PDR12, you syncs up the two sound tracts. Disable the sound from the video, so that only the imported sound from you sound recording device is on, and there you go.

I haven’t tried it mind you, but that is what the manual say.

Thanks, molan. I thought that may be the case. I was hoping the external audio track would lay down simultaneously and then you just delete the camcorder audio. That seems the most obvious solution to me. Looks I might wind up buying a legacy Panasonic DV camcorder with the external mic jack off ebay. I have a Tascam but the work-around seems like a hassle.
This seems such a common issue I'm surprised I can't find any info on it. Your's is the only answer I've received so far. Thanks again, amigo.

Good news is that PD12 lets you automatically sync multiple clips in the Multicam mode by doing audio analysis.
You can just record your audio separately as a WAV file, then import it and let the Multicam audio analysis do the synchronization with the video clip. It works great !

How your record the audio is another matter. You can use any digital recording device, including your computer. Most PCs have soundcards with recording inputs. Their quality greatly varies, though. Most built-in soundcards are fairly noisy on the recording side. You will use the soundcard as A/D converter and mic preamp.

If you decide to use the PC, it seems you can record audio using the Cyberlink Wave editor which comes with some editions of Powerdirector. I have not used that program. It seems fairly basic.

If you want to just record your voice in mono, you just need a single microphone. A single dynamic mic can be very cheap, maybe only $30. Make sure to get the right adapter cable for your soundcard.

For music, you will want at least 2 mics so you can do stereo. If you use condenser mics, you will also need a phantom power supply for each condenser mic. There are way too many choices to list, at all kinds of prices.

You can use something fully integrated with the A/D converter, preamp, and phantom power. Or you can use separate converter and preamp, which will cost more. Typically the the preamps have the phantom power option built-in.

For something fully integrated, a Focusrite Scarlett 2i2 USB audio interface costs about $150. That will get you two 96kHz stereo converters, 2 mic preamps, and phantom power. You can use pretty much any 2 mics with it.
Mics go from $20 to $10,000 and up so I won't go into that...

Personally, I use the Reaper program (http://www.reaper.fm) to record separate audio. It supports ASIO which allows recording more than 2 channels. I have an ECHO Audiofire 8a and another ECHO Audiofire 12 which let me record and play up to 28 channels (20 analog / 8 digital). I use Reaper to choose the best mic tracks and mix down to stereo.

Then I import the stereo WAV file into Powerdirector and sync with the video clip.
Until PD12 I was doing all the audio sync manually, aligning waveforms on the screen.
With PD12 multicam mode, it is much easier and automatic.
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