This driver's parameters were carefully optimized to match the performance of the classic Bose® 901® loudspeaker systems. Individually or in multiples, replacing your legendary but aging speakers has never been easier—or achieved better results.
Highlights
- Drop-in replacement for Bose 901 drivers
- Each individual driver is hand checked and tested
- Fits Series III, IV, V and VI models, and more
- Optimized cone/coil/suspension for linearity and reliability
- 1 ohm nominal impedance
- Premium-quality motor structure maximizes performance
Product details
GRS RSB901-1 Replacement Speaker Driver for Bose 901 4-1/2" 1 Ohm
This driver's parameters were carefully optimized to match the performance of the classic Bose® 901® loudspeaker systems. Individually or in multiples, replacing your legendary but aging speakers has never been easier—or achieved better results. The top plate and T-yoke are Japanese-made cold forged low carbon steel. The flat back plate provides a uniform surface area to which the magnet is bonded, and the outside of the back plate is chamfered to maximize flux density in the gap. Critical attention has been paid to the pole piece and voice coil tolerances, thereby assuring high yield and immunity to mechanical issues. High-grade Y-35 strontium ferrite magnet material is utilized in the motor structure to ensure consistent motor force. The cone is made of long fiber New Zealand blue color pulp paper, an ideal material for cone applications and the foam surround of this driver make it almost identical to the original manufacturers appearance, design and performance. It's rigid and just "lossy" enough to produce full, accurate sound. A 2-layer low oxygen copper voice coil is wound on a high temperature resistant polyimide former. Every driver is hand checked and tested, based on a ±2 dB window.
NOTE:This driver has an impedance of 1 ohm, and should be used only to replace the 4-1/2" driver in the Bose 901 (Series III or later) and Bose 802™ loudspeakers. Compatibility with other Bose loudspeaker models or automotive audio systems has not been verified. This product is not manufactured or distributed by Bose Corporation™, the owner of the registered trademarks BOSE®, BOSE 802™ and BOSE 901®.
Article numberRSB901-1
EAN0844632085055
Woofer TypeMidwoofer
Nominal Diameter4-1/2"
Power Handling (RMS)30 Watts
Power Handling (max)60 Watts
Impedance (Z)1 Ohm
Sensitivity (SPL at 1m / 2.83V)91.5 dB
Frequency Response83 to 15,000 Hz
Voice Coil Diameter1"
DC Resistance (Re)0.76 ohms
Voice Coil Inductance (Le)0.11 mH
Resonant Frequency (Fs)83.4 Hz
Mechanical Q (Qms)2.4
Electromagnetic Q (Qes)0.43
Total Q (Qts)0.36
Diaphragm Mass Inc. Airload (Mms)3.38g
Mechanical Compliance of Suspension (Cms)1.08 mm/N
Surface Area of Cone (Sd)66.6 cm2
BL Product (BL)1.767 Tm
Compliance Equivalent Volume (Vas)0.24 ft.³
Cone / Diaphragm MaterialPaper
Surround MaterialFoam
Voice Coil Wire MaterialCopper
Voice Coil FormerKapton® / Polyimide
Basket / Frame MaterialPolymer
Magnet MaterialFerrite
Overall Outside Diameter5.2"
Overall Depth2.17"
Baffle Cutout Diameter4.02"
# Mounting Holes3
Sealed Volume0.06 ft.³
Sealed F3182 Hz
Vented Volume0.14 ft.³
Vented F3104 Hz