It's as important as your loudspeaker design...
If you have ever spent time auditioning speakers under controlled circumstances, you know that consecutively produced speakers of the same model sometimes can sound very different. The difference can be as great as that found between speakers of di verse price ranges-a situation that challenges the validity of listening to a demonstration speaker and then purchasing another unit of the same model.
This problem resides in the measurements rather than in the speaker construction. It can occur whether the speakers are individually handmade or whether they are run on an assembly line.
In a university research program started by Dr. Bose in 1956 and in continuing research at BOSE Corporation, it has been found that some of the most commonly made measurements on speakers are not adequately correlated to the perception of sound. Extensive research has been performed to develop a set of measurements that correlate sufficiently to perception to provide a means of precise control of production speakers.
The result was a set of measurements that was not practical to implement with existing instruments.
At this point (1970), the BOSE research department launched a program to design a special purpose computer, programmed to test for audible differences and to interpret these differences in a manner that would allow production engineering to detect and correct the assembly problems.
The SYNCOM II speaker testing computer is the long awaited result of this extensive research program.
The Mountain, Framingham, MA 01701 USA
It is now installed and it is controlling all production on the BOSE 901 and 501 speakers. The technical details of this computer are, of course, a closely guarded proprietary secret, as is any technology that enables one company to produce better products in a competitive market. While we cannot share this information with you, we are confident that you will share in the results of SYNCOM II's operation through the enjoyment of more natural music re production in your home.
The BOSE Direct/Reflecting speakers and the SYNCOM II Computer are but two examples of the research of BOSE Corporation, founded by scientists and dedicated to continued leadership in the research of better music systems.
For information on the BOSE 901, write Dept.S4.
* For a description of the research, see the article entitled, "Sound Recording and Reproduction," published in TECHNOLOGY REVIEW (MIT), Vol. 75, No. 7, June '73. Reprints are available from BOSE for fifty cents per copy.
How to audition the BOSE 501...
Except for owners, very few people have really heard the new BOSE 501 SERIES II Direct/ Reflecting speaker. That's because it is designed for the home and not for the audio showroom--and there's a big difference. The 501 is designed to be placed against a wall with 18 inches clearance on each side-a condition that is met easily in the home, but not achieved in audio showrooms containing dozens of closely spaced speakers.
When the 501 is placed properly, its two side speakers radiate a component of sound rear ward to the wall (see above) to produce a stage-like performance that cannot be achieved by conventional direct radiating speakers.
The only way to audition the BOSE 501 is in the environment for which it is de signed. Visit a friend who owns 501s or ask your dealer for a pair on appraisal. If possible, compare them--in your own home--to the most expensive of the conventional direct radiating speakers. After this comparison, you will appreciate why there are no direct radiating BOSE speakers.
For further information on the BOSE 501, circle your reader service card or write Dept. S5.
The design, development, and technology behind the BOSE Direct/Reflecting speakers is presented by Dr. Bose in the article, "Sound Recording and Reproduction," published in TECHNOLOGY REVIEW (MIT), Vol. 75, No. 7, June '73.
Reprints are available from BOSE for fifty cents.
THE MOUNTAIN, FRAMINGHAM, MA. 01701 USA.
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