Yamamoto Sound Craft Large Wood Horn FA280A 1 unit

The FA280A has external dimensions of 806W x 330H x 513D, making it a large horn made of machined wood. Most conventional horns have a narrow aperture relative to the cutoff frequency, and most of them have a reduced frequency response below 1 KHz.

The conventional horns often use the exponential horn constant for horn spread, but this method tended to lower the frequency response near the cutoff. The FA280A can be used from 400 Hz, which is 1.5 times the cutoff frequency, by reviewing the normal frequency of the horn spread. The FA280A can be used from 400 Hz, which is 1.5 times the cutoff frequency.

F280A+TAD4001

f280a+jbl2445j

FA280AThe upper and lower boards of the FA280A and FA280J are carved from an extremely large block of laminated asada cherry wood measuring 810 x 470 x 142 mm. Each board weighs approximately 40 kg. The side panels are also cut from 62 mm thick laminated wood, requiring a total of nearly 100 kg of laminated wood per unit. Since laminated wood is manufactured by laminating raw wood into a board-like material, each horn requires nearly 250 kg of material from the original raw wood. This is the maximum amount of material that can be used for a horn machined from wood, and because it is machined, there is almost no horn squeal, and a clear reproduction sound is obtained, free from the horn squeal that accompanies large horns.

In the F280A, laminated wood boards are used vertically, facing forward and backward for superior sound transmission speed. As a result, the sound has a clear and speedy sound with good sound spread and release. The internal separator fins are located in the sound path and are thin and weak in terms of strength, so squeaking is a concern. The separator fins are made of very hard and strong African ebony wood, and are assembled in a way that the separator fins are sandwiched between the top and bottom boards with slots cut in them, thus ensuring sufficient strength despite the thin and sharp separator fins.

In order to further improve the vertical directivity of the horn, the vertical opening is designed to start closer to the throat and gradually open from near the throat. This allows vertical directivity to be controlled down to lower frequencies, resulting in a flatter and smoother frequency response with improved frequency response in the mid and low frequencies.

A horn is a device that determines the direction of sound by gradually increasing the volume of sound waves emitted from the driver unit in the sound path. Therefore, if there is an obstacle or a narrow area inside the sound path, sound reflections will occur there, causing the sound to be disturbed. Since this unit is not dimensionally calibrated at any position inside the horn, there is no disturbance of the characteristics due to reflections, and the characteristics of the sound are as smooth as possible. The directivity of this unit is 90 degrees in the horizontal direction × 40 degrees in the vertical direction, which is a reasonably wide directivity. If the directivity of the horn is too wide, it will be easily affected by room reflections. If it is too narrow, the direct sound from the horn tends to be strong and harsh. The directionality of this unit has a moderate directivity characteristic that is easy to hear in an ordinary listening room.

The FA280A uses a sufficiently strong throat adapter made of gunmetal. The internal construction stops at just converting from a 49 mm diameter round to a 50 mm x 60 mm square with a length of 60 mm. Inside the throat adapter, the sound wave spread is naturally guided to the horn, and the joint between the driver and the horn is firmly supported. Gunmetal, an alloy of tin and copper, is extremely strong and heavy, and is famous for its low squeal and beautiful resonance. The throat section alone weighs approximately 4 kg. This model is supported at three points for stability when setting up the horn by placing a pillar on the throat adapter made of gunmetal and a setting base on both sides of the horn. The sound of a horn can vary greatly depending on how it is set up. The three-point support reduces the effect of vibration from the woofer unit on the sound and improves the sound quality.