DIY 4ch audio mixer

1/7: High Quality DIY 4ch audio mixer

2/7: High Quality DIY 4ch audio mixer

3/7: High Quality DIY 4ch audio mixer

4/7: High Quality DIY 4ch audio mixer

5/7: High Quality DIY 4ch audio mixer

6/7: High Quality DIY 4ch audio mixer

7/7: High Quality DIY 4ch audio mixer