Bose 301 Series III Service Manual - Page 2

Browse online or download pdf Service Manual for Speakers Bose 301 Series III. Bose 301 Series III 13 pages. Direct/reflecting
Also for Bose 301 Series III: Owner's Manual (10 pages)

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BOSE

301 ™ SERIES III TECHNICAL DESCRIPTION

The BOSE 301 Series III System is an economical way to enjoy the legendary spatial

realism of a Direct/Reflecting

system. This system creates a natural balance of reflected

and direct sound that conventional speaker designs can't match. The result is lifelike

spaciousness that approaches the realism of a live performance. Even sound distribution

also enables the listener to sit or stand anywhere and still hear the same volume and blend

of musical instruments.

This achievement is also aided by three high performance drivers in each cabinet: one 8"

woofer and two 3" tweeters. The tweeters are arranged in a three-dimensional Free Space

Array which is mounted slightly away from the cabinet face. One tweeter is aimed inward

toward the center of the listening area. The second tweeter is aimed outward so that its

output is reflected off the side wall. This arrangement provides the excellent spatial

characteristics of a Direct/Reflecting

system.

The 301 system employs the BOSE Dual Frequency ™ crossover network. The crossover

provides a smooth transition from low to high frequencies by sending sound to all the

drivers over nearly a full octave. The result is a clear definition of each instrument and

voice.

Additionally, the system incorporates slot-port technology which reduces port noise and

produces cleaner, more natural bass. The sum of all these unique features makes the 301

Series III speaker capable of reproducing the wide dynamic range demanded by today's

advanced recordings without strain or loss of clarity.

TEST PROCEDURES

NOTE: Before performing any tests,remove the grille assembly. Refer to the Grille

Assembly Removal procedure.

1. Woofer Rub and Tick Test

A. Connect a sine wave oscillator to a power amplifier. Adjust the frequency of the oscillator

to 10 Hz and the amplifier output to 8 Vrms. Connect the amplifier output to the input

terminals of the 301-III speaker (see Figure 1). No extraneous noises such as rubbing,

scraping or ticking should be heard.