How to generate stereo sine wave using FFMPEG with different frequencies for each channel?

I'm trying to generate a stereo sine wave using FFMPEG (batch file), but have a different frequency for left and right. So far I have this:

ffmpeg -f lavfi -i "sine=frequency=1000:duration=60" -ac 2 "binaural.wav"

But it creates the same frequency for both left and right. Is this possible?

Solution

Use two sine filters and merge them.

ffmpeg -f lavfi -i "sine=frequency=1000:duration=60" -f lavfi -i "sine=frequency=600:duration=60" -filter_complex amerge  "binaural.wav"