Page 1
Congratulations ! You are now the proud owner of a Pioneer R-series speaker system, To make full use of its astounding potentials and to avoid errors in its placement, connection and operation, please study the following instructions carefully.
ABOUT THE PIONEER R.SERIES
With the new R-series, Pioneer introduces a new
concept in speaker system design: the individualistic
speaker. Even at the first glance, these speakers look different, with their two-part front grilles and powerful-looking, massive enclosures. But connect a pair of Pioneer R-series speakers to a good stereo
amplifier, play a pro$am of rock, jazz or folk music, and you'll realize that these speakers are different. We've designed them with the emphasis on impact and richness rather than on laboratory data. That's what makes Pioneer R-series speakers so ideally suited for modern music while also lending a new feel to the classical repertoire.
THE SOUND OF ..LIGHT POWER"
Compared with conventional designs, Pioneer R-
series speakers sound somewhat brighter and at the same time richer. This effect was achieved by a care- fully selected and tested combination of numerous factors: selection of special material for the woofer cone, balancing of the different speaker units, selec- tion of crossover network constants, adoption of the bass reflex principle in the enclosure - without, however, causing that notorious "boominess" of bass reflex constructions.
CAREFULLY BALANCED BASS REFLEX
DESIGN
In a bass reflex system (in which the sound waves from the rear side of the woofer are reflected, re- versed in phase and radiated to the front through a special port), careful selection and balancing of the speaker units and of numerous other design para- meters is extraordinarily important. In the Pioneer R-series, a partition of sound absorbing material is provided in the enclosure, preventing mutual inter- ference of the speaker units and avoiding "standing waves." This and the careful dimensioning of the port lends these speaker systems their crisp bass re- sponse. What seemed to be impossible has been realized: speaker sound that is momentous without being boomy, modern without being untrue to the original.
Page 2
FEATURES
25 cm Cone-type Woofer
Use of newly developed FB cone paper improves frequency
response and gives the woofer its excellent transient charac- teristics. The cone surface is especially coated over to avoid partial vibrations, thereby resulting in vastly improving
transient characteristics and tonal qualify.
The woofer edge is made of soft polyurethane foam which prevents distortions due to edge resonances and improves stability under various temperature and humidity condi- t ion s.
To permit high power input and to avoid distortions caused
by transient bass impulses, a long-throw voice coil and an aluminu m sheet bobbin are used.
A large 12cm ferrite magnet with a pure copper cap on its
center pole suppresses harmonic distortions, however little, in the middle range.
'12 cm Cone-type Mid-range Speaker
The mid-range speaker, too, employs a cone made of special FB paper with its extra strong magnet, its newly adopted center cap combined with rigid duralumin and damper, and its hermetically sealed back chamber. Therefore, this speak- er lends itself to superb reproduction of the all-important
mid sound range with excellent response and freedom from
d istortions.
Horn Tweeter
The diaphragm is made of a special polyester-type synthetic resin with excellent stability against changes in temperature and humidity, and is vapor-coated with aluminum. Togeth- er with the aluminum diecast horn, this construction ex- plains the very flat frequency response up to an ultra-high
range and the wide sound dispersion angle. The high and very high sound range has impact and presence from any listening position.
Network
Design provides for optimum speaker system frequency response. Stringent component selection and use of a com- pensating circuit designed to limit woofer and mid range
impedances guarantee ideal transmission characteristics a- round the crossover point, as well as good transient charac- teristics. (Refer to Figs. 1 and 2.)
i----l fI IMPEDANCECOMPENSATINGCIRCUIT
O-(^
@
@lmpedance curve for speaker alone. @lmpedance curve with copper cap at magnetic path Pole. @lmpedance curve with compensating circuit added. Fig. 1 Fi9.2
UIoz
or!0_
SPEAKER
2
