JBL 4348 owner manual Maintenance, Specifications

Studio Monitor Model 4348

7: Maintenance

•When doing any maintenance, wipe the surface of the cabinet with a dry cloth to remove dust. Damp cloth or cleaning paper may dull the finish on the cabinet surface. Do not use volatile liquids such as benzene, paint thinner, alcohol, etc, and do not spray insecticide near it.

•If dust gets into the grill netting, use a vacuum cleaner to remove it. In doing so, adjust the suction power of the vacuum cleaner so that it does not suction too strongly. Furthermore, do not wash the grill in water. The grill may sag or its color may become uneven.

•If the surface of the speaker unit becomes dusty, use a soft, dry calligraphy brush or a paint brush to carefully sweep the dust away. Never use a damp cloth.

•The speaker system is a durable consumer good. In particular, the edges of the woofer, which support rapid movement of the paper cone, undergo a great level of stress, and there is a limit to the number of years of its practical use. Also, the speakers' lifespan may be shortened by the effects of temperature, humidity or ultra-violet radiation. Please avoid exposing the speaker to strong lighting such as from lighting equipment or direct sunlight and avoid placing the speakers in high temperatures such as near the air conditioner exhaust pipe or a heat radiator.

<Bias Battery>

In this system, JBL's unique charge coupling method is used, in which a direct bias is constantly applied to the condensers in the network circuit to activate the elements, removing zero crossover distortion.

This battery has a life of about two years. Even if the battery voltage drops, there is no impediment to the network function. However, in order to maintain superior sound quality, we recommend that you change the battery periodically. Like the network mode switch, unscrew the screws for the subhatch at the top on the rear-panel and remove the hatch to change the battery.

When doing so, check the positive and negative sides of the battery (9V, rectangular 006P type battery) and install it correctly.

The battery included in the shipped system is for testing purpose only. We recommend that you replace it as soon as possible.

8: Specifications

Type	4-way floor type
Units used	38 cm pure pulp cone woofer 1500FE
	25 cm fiber composite cone/mid-range transducer 2251J-1
	75 mm aluminum compression driver 435AI
	25 mm pure titanium compression driver 045Ti
Impedance	6 Ω
Allowable input	400 W (RMS)
Output sound pressure	95 dB (2.83 V/1m)
level
Frequency response	33 Hz – 40 KHz (-6 dB)
Crossover frequencies	300 Hz, 1 kHz, 10 kHz
Dimensions (W x H x D)	597 x 1080 x 400 mm (with grill 425 mm)
Weight	90.4 kg