LF
Woofer
8"
81FHW
Code: DR-8-006-4R-B2-C0001
Woofer/8inch/Ferrite/Paper/100W/4ohm
Key Features
- Good low frequency response
- Lightweight surround, stiff paper cone
- Affordable woofer
Quick Specs
Impedance
4 Ω
Program Power
200 W
Sensitivity
85.94 dB
Fs
39.00 Hz
Magnet
Ferrite
Voice Coil
35.6 mm
Design Notes
The 81FHW woofer was designed with smaller hi-fi subwoofers in mind. The woofer works well in vented enclosures or combined with a passive radiator. Optimized magnetic structure delivers good level of performance and balancing well performance vs cost.
We have chosen lightweight foam surround in this design. Our extensive development and testing of this material yielded in custom formulation of the raw material we use for the surround and guaranties its long lasting performance.
We have chosen lightweight foam surround in this design. Our extensive development and testing of this material yielded in custom formulation of the raw material we use for the surround and guaranties its long lasting performance.
Specifications
General Specs
Nominal Diameter
8"
Rated Impedance
4 Ohm
Magnet
Ferrite
Basket Material
Steel
Power Handling
AES Power
100 W
Continuous Power
200 W
Peak Power
400 W
Voice Coil
Diameter
35.6 mm
Winding Wire
Copper
Former
Aluminum
Winding Height
18.2 mm
T/S Parameters
Resonant Frequency (Fs)
39.00 Hz
Re
3.60 \u2126
Qes
0.580
Qms
5.40
Qts
0.520
Vas
21.50 liters
Sd
201.10 cm\u00B2
Mms
44.00 grams
Rms
2.00
Cms
0.3800
Bl
8.25 T\u00B7m
Le
1.120 mH
Sensitivity
85.94 dB
Design Details
Surround Material
Foam
Cone/Dome Material
Paper GF
Spider
Nomex
T-Plate
6 mm
Xmax (peak)
6.1 mm
Xmech
12.1 mm
Overall Diameter
209.00 mm
Bolt Circle Diameter
197.00 mm
Baffle Cutout Dia.
180.00 mm
Mounting Holes
8
Depth (flange to rear)
95.00 mm
Net Weight
1.70 kg
Ordering Codes
Product Code
DR-8-006-4R-B2-C0001
Downloads
Frequency Response & Impedance
2D Drawing
Technical Summary
The 81FHWX4-289 is an 8-inch sub-woofer driver designed for compact hi-fi subwoofer systems, home audio, and cost-effective installation applications. It operates at 85.9 dB sensitivity (1W/1m) and features a compliant suspension design suited to moderate-volume vented or passive-radiator enclosures with extended low-frequency response.
The driver is intended for use with moderate amplification (approx. 100 W AES / 200 W continuous) and DSP control. A high-pass filter in the range of 25-37 Hz is recommended depending on enclosure tuning, along with appropriate limiting to manage excursion below tuning. Typical operating bandwidth is 31-100 Hz, suitable for integration with a mid-bass or full-range driver in a two-way system.
This design is well suited for single-driver compact bass reflex or passive-radiator enclosures in hi-fi, home theater, and cost-conscious installation applications, where a balance of low-frequency extension, compactness, and value are the primary priorities.
The driver is intended for use with moderate amplification (approx. 100 W AES / 200 W continuous) and DSP control. A high-pass filter in the range of 25-37 Hz is recommended depending on enclosure tuning, along with appropriate limiting to manage excursion below tuning. Typical operating bandwidth is 31-100 Hz, suitable for integration with a mid-bass or full-range driver in a two-way system.
This design is well suited for single-driver compact bass reflex or passive-radiator enclosures in hi-fi, home theater, and cost-conscious installation applications, where a balance of low-frequency extension, compactness, and value are the primary priorities.
Recommended enclosure volumes are simulated results. For best enclosure volumes and tuning, we recommend secondary simulation and careful evaluation. Several rounds of samples and fine-tuning may be required for optimal results.
Enclosure Recommendations
Recommended enclosure alignments (bass reflex): - 10 liters tuned to 45 Hz: high output, strong mid-bass, reduced excursion; -3 dB approx. 41 Hz, HP filter 37 Hz - 12 liters tuned to 41 Hz: balanced response, general-purpose (recommended); -3 dB approx. 38 Hz, HP filter 31 Hz - 16 liters tuned to 37 Hz: extended low-frequency, requires HP filter protection; -3 dB approx. 31 Hz, HP filter 25 Hz
Frequently Asked Questions
- - Good low frequency response
- - Lightweight surround, stiff paper cone
- - Affordable woofer
Recommended enclosure alignments (bass reflex): - 10 liters tuned to 45 Hz: high output, strong mid-bass, reduced excursion; -3 dB approx. 41 Hz, HP filter 37 Hz - 12 liters tuned to 41 Hz: balanced response, general-purpose (recommended); -3 dB approx. 38 Hz, HP filter 31 Hz - 16 liters tuned to 37 Hz: extended low-frequency, requires HP filter protection; -3 dB approx. 31 Hz, HP filter 25 Hz
Sealed or vented pa mid-woofer, 2-way compact top
AES Power: 100 W,
Continuous: 200 W,
Peak: 400 W.
Sensitivity: 85.94 dB (1W/1m).
