The Blackline F215 is a two-way passive, trapezoidal enclosure with dual 15" (380mm) / 3" (75mm) coil low frequency drivers. Whilst both these drivers have the same low frequency characteristics and operate together up to 250Hz, they have been engineered to have different characteristics in the midband. Above 250Hz, only the upper driver - a specially designed, low distortion bass-mid device – is used up to the 1.3kHz crossover point. This technique avoids the uneven response which would occur if both drivers were allowed to operate together over the mid-band and maintains clarity and articulation at extreme output levels.

High frequencies are reproduced by a 1.4" (35mm) exit titanium diaphragm compression driver, loaded by a propriety rotatable 80° x 50° constant directivity horn.