Adding Sound Effects to existing MMD animations

A Feature Article by Reggie Dentmore on

Adding sound effects at just the right time is a challenge.  How do I time a new sound fx? How do I calculate the timing of a new sound effect?

Adding Sound Effects to existing MMD animations …

In my latest video, Bored, I created the animation for the lamp-switching scene before I got around to adding the sound effect for those actions.

I was expecting it to be a challenge … adding those sound effects at exactly the right moments without a lot of trial and error.

Simple mathematics …

It turned out that only a bit of simple math was required.

I opened my MMD animation and determined that the motion started at frame 2723.

Adding sound effects to an existing animation can be a challenge!

The math: we know that my animation runs at 30-frames per second. 2723 frames divided by 30 equals 90.7666 seconds.

90.7666 seconds divided by 60 seconds/minute equals 1.51277 minutes.

to find the number of seconds in .51277 of a minute, we multiply that number by 60 seconds.

.51277 x 60 = 30.766 seconds …

So … at 1 minute, 30.766 seconds, I want to paste my sound effect.

I opened my Audacity® software (get the link to the free Audacity audio software from the LearnMMD Downloads page) and imported my existing soundtrack WAV file. I Clicked to “add a new track”. I had previously recorded my “pull-chain” sound effect … so I opened it in a new Audacity window, selected the sound-segment that I wanted to use and clicked COPY to put that sound into memory.

Finally … find the exact moment you are looking for. I wanted to paste my sound effect at one-minute, 30.77 seconds. Click Audacity’s magnifying-glass tool to zero-in on your moment …

I needed to pin-point one-minute, 30.77 seconds.

… and when you see it … Click to place the cursor upon your moment and then click PASTE (Control-v) to set your sound effect into place.

I needed to use the “pull-chain” noise several times …. and so had to “do the math” several times … once for each pull of the switch.

I had to place the same sound effect several times.

To finish the project, SAVE the Project before you go to the next step. Saving, now, will leave the saved file with separate tracks so that you can make changes later, if needed.

Now, Control-A (Select All) and then, under the TRACK menu, choose “Mix and Render”, which combines the separate tracks into a single track. Now, under the FILE menu, choose EXPORT and choose the “WAV (Microsoft) 16 bit PCM” format … and you are done.

Close Audacity and DO NOT SAVE the final Audacity Project … you want to keep those separate tracks that you have already saved.

As usual … all of this took much longer to write about, and read about, than it takes to actually perform the operation. It will be easy once you learn how to do it.

— Enjoy!


Visit the Homepage! Plenty of Mikumikudance instruction and info!