ravic, your dimensions are not correct. It seems that you used a very thick MDF.

The top box external dimensions should be 27x28x11cm
If we deducted the MDF thickness (1cm average) it should be 26x27x10cm = 7.02 litres

The bottom box external should be 28x24x6cm
Internal 27x23x5cm = 3.11 litres

Total is 10.2 litres approx

Pioneer says minimum 9.9 - recommended 12.7 - maximum 19.8

So we are within the range.

The sub would not fit from the face if it is 25.2x24.4cm as u mentioned. The outer diameter of the sub is 27.8cm

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