Unity Horn

Three-way entry horn with 3D-printed double compression throat adapter.

Over a stay in NYC, we had the chance to check out installations of well-known Unity horns. It sparked our interest in designing one to better understand its principles. The result is a 55° x 55° horn housing two 12" and six 4" speakers. A special throat adapter has been designed for mounting two compression drivers and effectively halve their output distortion.

Bookshelf Speaker

Small-scale speaker with three-cell wooden horn and 3D-printed throat adapter.

This bookshelf speaker comprises a three-cell horn providing an horizontal dispersion of 60° to a 1" compression driver. The horn entry point is physically aligned for a cross-over at 1 KHz. This insures a coherent dispersion throughout the spectrum. The woofer is a high quality 8" driver tuned to 48 Hz.

Side view of the subwoofer with access trap open

Front-Loaded Horn Subwoofer

Dual 18" subwoofer with stepped front loading.

This subwoofer is a good fit for both fixed and touring installations. It comprises two 18" RCF drivers front loaded with a stepped folded horn of 500+ liters in a 145 x 78 x 64 cm cabinet. Bracing ensures the proper rigidity of the cabinet. A single unit can accept 2400 Watts at 4 Ohm while reaching down to 45 Hz at -3dB. Stacking two units extend their reach to 42 Hz, while stacking four go as low as 38 Hz. The graph shows frequency reponses for these combinations at 1 Watt in half space radiation.