LF
Fullrange
4"
41FR
Code: DR-4-003-8R-B2-C0001
Variant of DR-4-003
Key Features
- Very good performance at affordable price
- Excellent HF extension
- Array applications, 2-way systems, can be used without HF unit
Quick Specs
Impedance
8 Ω
Program Power
40 W
Sensitivity
89.44 dB
Fs
134.00 Hz
Magnet
Ferrite
Voice Coil
25.4 mm
Design Notes
41FR is ferrite based mid-woofer, developed for applications where small size mid-woofer is required. This version was developed with extended HF response and in some cases could be used as full-range driver. Yet, this driver delivers very good performance low frequency range as well.
Our engineers have chosen lightweight, yet strong, paper cone with rubber surround. Cone optimized shape brings remarkable strength of the piston and greatly improves harmonic distortion artifacts.
Overall this model delivers very good performance and is well balanced between performance - cost.
Our engineers have chosen lightweight, yet strong, paper cone with rubber surround. Cone optimized shape brings remarkable strength of the piston and greatly improves harmonic distortion artifacts.
Overall this model delivers very good performance and is well balanced between performance - cost.
Specifications
General Specs
Nominal Diameter
4"
Rated Impedance
8 Ohm
Magnet
Ferrite
Basket Material
Steel
Power Handling
AES Power
20 W
Continuous Power
40 W
Peak Power
80 W
Voice Coil
Diameter
25.4 mm
Winding Wire
CCAW
Former
kapton
Winding Height
7.2 mm
T/S Parameters
Resonant Frequency (Fs)
134.00 Hz
Re
5.60 \u2126
Qes
0.810
Qms
10.60
Qts
0.750
Vas
1.30 liters
Sd
50.30 cm\u00B2
Mms
3.80 grams
Rms
0.30
Cms
0.3700
Bl
4.78 T\u00B7m
Le
0.090 mH
Sensitivity
89.44 dB
Design Details
Surround Material
NBR
Cone/Dome Material
Paper CF
Spider
Nomex
T-Plate
5 mm
Xmax (peak)
1.1 mm
Xmech
6.1 mm
Overall Diameter
105.50 mm
Bolt Circle Diameter
106.00 mm
Baffle Cutout Dia.
93.60 mm
Mounting Holes
4
Depth (flange to rear)
55.90 mm
Net Weight
0.78 kg
Ordering Codes
Product Code
DR-4-003-8R-B2-C0001
Frequency Response & Impedance
2D Drawing
Technical Summary
The 41FRX8-360B is a 4-inch full-range / mid-woofer driver featuring a ferrite magnet
motor, steel basket, carbon fiber reinforced paper cone with optimized geometry profile,
NBR rubber surround, Nomex spider, and a 25.4mm CCAW voice coil wound on a Kapton former.
The CCAW winding minimizes voice coil mass (Mms = 3.8 g) and inductance (Le = 0.09 mH -
the lowest in the full-range family), contributing directly to the driver's high sensitivity
and the inductance rolloff onset of 9,911 Hz - effectively placing the impedance rolloff
above the audible range. The driver is positioned for dual use: as a small mid-woofer in
2-way systems and as a standalone full-range driver in column arrays and desktop speakers.
The manufacturer explicitly notes it can be used without a high-frequency unit. The 8ohm
nominal impedance and ferrite motor construction provide a cost-effective, standard-load
solution for column array and 2-way enclosure designs.
Enclosure alignments:
- Free-air / open-back (primary - full-range and column array use):
f-3dB approx. 127 Hz; <0.1 dB resonance deviation (no EQ correction required)
High-pass filter at 90-110 Hz recommended in all installations
- Sealed (secondary - mid-woofer in 2-way system, crossed to tweeter):
0.55 L / Qtc = 0.85 / fc = 161 Hz / f-3dB = 138 Hz
0.24 L / Qtc = 1.00 / fc = 191 Hz / f-3dB = 150 Hz
0.10 L / Qtc = 1.20 / fc = 229 Hz / f-3dB = 169 Hz
In column array applications, the 105.5 mm driver OD limits coherent vertical directivity
to approximately 1.63 kHz - the lowest in the full-range family; a co-located tweeter is
mandatory. In standalone full-range installations without a tweeter, progressive HF
beaming above 2,737 Hz is characteristic of the 4-inch cone size; a 2-4 dB DSP HF shelf
may extend perceived HF coverage in near-field or close-proximity applications. A high-
pass filter at 90-110 Hz is recommended in all free-air installations to protect against
excursion over-excursion below the natural rolloff frequency.
The 41FRX8-360B is suited for column speaker arrays requiring a maximally-flat free-air
bass response from a 4-inch ferrite driver without DSP bass correction; 2-way desktop,
bookshelf, and column enclosures where the driver covers bass and midrange in a sealed
alignment (0.10-0.55 L) crossed to a tweeter at 2,000-3,000 Hz; standalone full-range
use in near-field and desktop applications where the extended HF response (f_Le = 9,911 Hz)
and low Le make a tweeter optional; and cost-sensitive installed sound systems where ferrite
motor construction, standard 8ohm impedance, and high sensitivity (101.0 dB max SPL) provide
a practical and affordable full-range solution.
motor, steel basket, carbon fiber reinforced paper cone with optimized geometry profile,
NBR rubber surround, Nomex spider, and a 25.4mm CCAW voice coil wound on a Kapton former.
The CCAW winding minimizes voice coil mass (Mms = 3.8 g) and inductance (Le = 0.09 mH -
the lowest in the full-range family), contributing directly to the driver's high sensitivity
and the inductance rolloff onset of 9,911 Hz - effectively placing the impedance rolloff
above the audible range. The driver is positioned for dual use: as a small mid-woofer in
2-way systems and as a standalone full-range driver in column arrays and desktop speakers.
The manufacturer explicitly notes it can be used without a high-frequency unit. The 8ohm
nominal impedance and ferrite motor construction provide a cost-effective, standard-load
solution for column array and 2-way enclosure designs.
Enclosure alignments:
- Free-air / open-back (primary - full-range and column array use):
f-3dB approx. 127 Hz; <0.1 dB resonance deviation (no EQ correction required)
High-pass filter at 90-110 Hz recommended in all installations
- Sealed (secondary - mid-woofer in 2-way system, crossed to tweeter):
0.55 L / Qtc = 0.85 / fc = 161 Hz / f-3dB = 138 Hz
0.24 L / Qtc = 1.00 / fc = 191 Hz / f-3dB = 150 Hz
0.10 L / Qtc = 1.20 / fc = 229 Hz / f-3dB = 169 Hz
In column array applications, the 105.5 mm driver OD limits coherent vertical directivity
to approximately 1.63 kHz - the lowest in the full-range family; a co-located tweeter is
mandatory. In standalone full-range installations without a tweeter, progressive HF
beaming above 2,737 Hz is characteristic of the 4-inch cone size; a 2-4 dB DSP HF shelf
may extend perceived HF coverage in near-field or close-proximity applications. A high-
pass filter at 90-110 Hz is recommended in all free-air installations to protect against
excursion over-excursion below the natural rolloff frequency.
The 41FRX8-360B is suited for column speaker arrays requiring a maximally-flat free-air
bass response from a 4-inch ferrite driver without DSP bass correction; 2-way desktop,
bookshelf, and column enclosures where the driver covers bass and midrange in a sealed
alignment (0.10-0.55 L) crossed to a tweeter at 2,000-3,000 Hz; standalone full-range
use in near-field and desktop applications where the extended HF response (f_Le = 9,911 Hz)
and low Le make a tweeter optional; and cost-sensitive installed sound systems where ferrite
motor construction, standard 8ohm impedance, and high sensitivity (101.0 dB max SPL) provide
a practical and affordable full-range solution.
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
The 41FRX8-360B is primarily suited to very compact sealed enclosures and near-field desktop applications (Fs = 134 Hz, Qts = 0.75, Vas = 1.3 liters). Practical sealed volumes are: - 0.10 liters (Qtc approx. 1.3): ultra-compact sealed for panel-mounted near-field systems; system resonance approx. 205 Hz; requires HP crossover at 2,000-3,000 Hz - 0.25 liters (Qtc approx. 1.1): compact desktop enclosure; system resonance approx. 178 Hz; best matched with tweeter crossover at 2.5 kHz - 0.55 liters (Qtc approx. 0.9): small sealed enclosure; system resonance approx. 162 Hz; usable as standalone full-range in near-field with no tweeter Free-air and open-back baffle installations are viable for extended HF coverage; the ferrite motor provides adequate mechanical control in unenclosed configurations.
Frequently Asked Questions
- - Very good performance at affordable price
- - Excellent HF extension
- - Array applications, 2-way systems, can be used without HF unit
The 41FRX8-360B is primarily suited to very compact sealed enclosures and near-field desktop applications (Fs = 134 Hz, Qts = 0.75, Vas = 1.3 liters). Practical sealed volumes are: - 0.10 liters (Qtc approx. 1.3): ultra-compact sealed for panel-mounted near-field systems; system resonance approx. 205 Hz; requires HP crossover at 2,000-3,000 Hz - 0.25 liters (Qtc approx. 1.1): compact desktop enclosure; system resonance approx. 178 Hz; best matched with tweeter crossover at 2.5 kHz - 0.55 liters (Qtc approx. 0.9): small sealed enclosure; system resonance approx. 162 Hz; usable as standalone full-range in near-field with no tweeter Free-air and open-back baffle installations are viable for extended HF coverage; the ferrite motor provides adequate mechanical control in unenclosed configurations.
Pa column midrange, small two-way monitors
AES Power: 20 W,
Continuous: 40 W,
Peak: 80 W.
Sensitivity: 89.44 dB (1W/1m).
