JBL 4301B

 JBL 4301B   2-way Broadcast Monitor, this smallest monitor is designed primarily for the broadvast control room and edit booth, and has achieved wide acceptance in home studios, remote recording and quality controlareas. Smooth, wide range response and low distortion are obtained from 200 mm (8 ") low frequency and 36 mm (1,4") high frequency loudspeakers. A high frequency level control is provided on the front baffle. Available in oiled walnut with dark blue grille.

The 4301B shares its basic performance characteristics with all other JBL monitors - exceptional clarity, wide dynamic range, solid bass and open high frequency reproduction. The 4301B is efficient enough to produce a sound pressure level of 98 dB in a typical broadcast booth of 1,8 m x 3,0 m x 2,4 m with an amplifier delivering only 10 watts rms. The compact enclosure of the 4301B is designed to fit the smaller spaces typical of broadcast control booths, production studios or mobile recording , broadcast and film editing facilities.

Frequency Dividing Network

Smooth control of the component loudspeakers is achieved by a frequency dividing network engineered and tested to complement the electrical and acoustical character istics of the system. The dividing network is fitted with a continuosly variable control that permits adjusting the relative level of the high frequency direct radiator to suit listening preferences and room conditions. The control does not affect the crossover frequency, not does it limit the upper frequency response of the loudspeaker system. 

 High Frequency Direct Radiator

The open, crisp treble performance of the 4301B is the product of a 36 mm (1,4") direct radiator designed for clarity, smoothness of response and power handling capacity the 16 mm (5/8") copper voice coil is large in relation to cone size for efficiency and transient reproduction with definition and accuracy, yet the diameter of the cone and center dome has been kept small to obtain wide dispersion. The magnetic assembly weighs 0,74 kg and generates a flux density of 1,5 tesla.

The 4301B utilizes a low frequency loudspeaker specifically engineered for a compact enclosure without the compromises usually associated with smaller drivers. The 200 mm (8") loudspeaker exhibits unusually smooth frequency response, wide dynamic range, superior transient reproduction and low distortion for a unit of compact size. It features a precision die-cast aluminum frame for structural integity under the most severe operating conditions. The 50 mm (2:) diameter copper voice coil is suspended in a magnetic  field having a flux density of 0,85 tesla. The magnetic field is generated by a 1,28 kg (3 lb) low-loss magnetic assembly. Mass and compliance of the integrally stiffened cone have been carefully selected to optimize low frequency bandwidth and definition while reducing distortion. As with all JBL loudspeakers, this unit provides maximum power handling capacity and efficiency consistent with the bandwidth expected of the device.

 Enclosure

Size and configuration of the 4301B enclosure have been carefully matched to the acoustic characteristics of the component loudspeakers as well as the intended use of the complete system. To achieve maximum strength and resistance to vibration, all enclosure joints are hand fitted; all panels are constructed of 19 mm dense compressed stock. Acoustic damping material is applied to the interior surfaces of the side and back panels to attenuate standing waves within the enclosure. A ducted port extending through the baffle panel provides proper acoustical loading of the low frequency loudspeaker. All components mount directly to the baffle panel and are removable from the front of thr enclosure. The four side panels are veneered with solid American black walnut, hand rubbed to a rich, lustrous finish enhancing the natural beauty of individual grain structure and color.

Specifications

Frequency Response:  45 Hz - 15 kHz (±3 dB)

Power Capacity:  15 W (Continuous Sine Wave)

Nominal Impedance: 8 Ω

Power Output:  88 dB SPL (measured at 3 m in a room volume of 57 m³ with an average absorption of 18,6 m² at ½ rated power input , -3 dB)

Sensitivity (1 W at 1 m):  88 dB SPL

Distortion (½ Power, 87 dB SPL/3 m. single Frequency):  0,5% or less third harmonic generation from 100 to 15,000 Hz

Crossover Frequencies:  2,5 kHz

Polar Response:  no less than -6 dB at 90° horizontal and vertical to 10 kHz

Enclosure Volume:  30 litres

Dimensions (H x W x D):  483 x 292 x 306 mm (19" x 11½" x 12⅛")

Weight (net):  12,7 kg (28 lbs)