LS5/12A Grade 1 Miniature Monitor Loudspeaker which BBC developed as a new reference of a
small speaker. Grade1 meant it as the monitor speaker of the highest grade used for the voice check in the stage before sending to a transmitter from studio, and LS5/8, LS5/9, LS5/12A, etc. were
Incidentally, let LS3/5A be grades 2 by the object for the check of a speech program.
15W7508BBC (product made from Dynaudio) which is a 11.5cm corn type Woofer is adopted as low-pass.
The reappearance capability stabilized using a 7.5cm large caliber aluminum voice coil has been acquired.
D-260BBC (product made from Dynaudio) which is a dome shape tweeter of a 2.8cm caliber is adopted as a high region.
this unit ferrofluid cooling is adopted and durability is improved by promoting thermal diffusion when a voice coil becomes a high fever by applying magnetic oil to a voice coil.
Moreover, low distortion has been obtained with Tran Gent excellent in molding and dumping a rear chain bar carefully.
The seal dead magnet which prevents a magnetic flux leak is used for a unit, and the use as a TV monitor is also attained.
By having made the characteristic of the unit smooth, the network part enables simple-ization and has eliminated the complicated characteristic compensation network. Moreover, the component of highest-class grades, such as an air core inductor, is used, and the substrate is also using usual not 1 oz but 5-oz copper.
Enclosure is designed based on CAD, is divided to a rear bass-reflex port for the purpose of gaining low-pass [ rich ] from small capacity, and is carrying out careful consideration. As compared with enclosure size, the big port caliber was adopted as this bass-reflex port at the exception, and the low-pass response is improved by optimizing form and structure.
Moreover, acoustic diffraction is prevented by performing round processing to a front baffle.
Finish is rosewood finish.
The thing of bi-wiring connection correspondence and banana plug specification is adopted as a speaker terminal.
The smooth characteristic and an allowable input were given to each unit, and also what cleared the standard of a permissible error of less than 0.25dB is adopted.
The final balance of a system gathers the pros of each field in the studio of BBC, is optimizing them by the intensive audition of comparing the sound of a speaker output and a live performance etc., and is polished up with emphasis on the reproducibility not only in the theoretical measured
value in an anechoic room but an actual operating condition.
|Rating of a mode|
2 way, 2 speaker bass-reflex system, and book shelf type
- Simple magnetic-shield type
For low-pass: 11.5cm corn type (15W7508BBC)
For high regions: 2.8cm dome shape (D-260BBC)
80Hz-20kHz±3dB (at the time of 2m and grill wearing)
|Pair matching||Less than 0.75dB|
|Output sound pressure level||81.5dB/W/m|
|The maximum input||50W-150W|
|Dimensions||Width 184x height 295x depth of 227mm|