ND91-8 3-1/2" Aluminum Cone Full-Range Driver 8 Ohm

Quick Overview

The Dayton Audio ND91-8 3-1/2" Neo-Balanced driver balances low distortion, extended range, and surprising bass impact. Its sophisticated motor design provides the underhung 1" voice coil with extended linear travel within the magnetic field.

Product Highlights

  • Low distortion, full-range 65 Hz to 17 kHz performance
  • Rubber-edged black anodized aluminum alloy cone
  • Large excursion capability — 4.6 mm Xmax, 25 mm peak
  • Self-shielded Neo-Balanced motor structure with copper alloy shorting ring
  • 1" 4-layer underhung voice coil with polyimide former
  • 30 watts RMS power handling
  • Great for line arrays and micro monitors

Product Manuals / Spec Sheets / Downloads

Dayton Audio ND91-8 Specification Sheet
Dayton Audio ND91-8 Klippel Test Results
Dayton Audio ND91-8 Data Files

Buying Options

Dayton Audios ND91 aluminum cone full-range drivers are the latest addition to the acclaimed ND Series high output/low distortion neodymium transducers. By increasing the original ND90s voice coil diameter from 3/4" to 1" and adding a copper alloy shorting ring, the ND91-8 features even lower distortion and delivers better bass impact and dynamic range—with peak Xmax up to 25 mm!

This high-BL version further exploits the low distortion characteristics of the Neo-Balanced motors optimized magnetic field, making the ND91 drivers an excellent choice for full-range point-source speaker enclosures, as well as extremely accurate, high resolution line arrays.


Sealed Volume 0.02 ft.³
Sealed F3 139 Hz
Vented Volume 0.04 ft.³
Vented F3 75 Hz
* Enclosure volume/F3s based on BassBox "optimum" calculations

Speaker Series ND Series
Model Number ND91-8
Color Black
Unit of Measure Each
UPC 844632090455
Warranty - Parts 5 Years
Warranty - Labor 5 Years
Product Shipping Weight (lbs.) 0.7
Speaker Type Full-Range
Nominal Diameter 3.50"
Power Handling (RMS) 30 watts
Power Handling (max) 60 watts
Continuous Program Power --
Impedance 8 ohms
Sensitivity 82.1 dB @ 2.83V/1m
Frequency Response 70 - 17,000 Hz
Voice Coil Diameter 25 mm
Magnet Weight --
DC Resistance (Re) 7.8 ohms
Voice Coil Inductance (Le) 1.24 mH @ 1 kHz
Resonant Frequency (Fs) 70.7 Hz
Mechanical Q (Qms) 4.29
Electromagnetic Q (Qes) 0.53
Total Q (Qts) 0.47
Diaphragm Mass Inc. Airload (Mms) 4.8g
Moving Mass Of Diaphragm (Mmd) --
Mechanical Compliance of Suspension (Cms) 1.05 mm/N
Surface Area Of Cone (Sd) 30.4 cm²
Volume of Displacement (Vd) 12.2 cm³
BL Product (BL) 5.63 Tm
Compliance Equivalent Volume (Vas) 1.53 liters
Maximum Linear Excursion (Xmax) 5.1 mm
Drivers Mechanical Losses (Rms) --
Cone / Diaphragm Material Aluminum Cone
Entry / Exit Diameter --
Surround Material Rubber
Voice Coil Wire Material Aluminum
Voice Coil Former Kapton® / Polyimide
Basket/Frame Material Steel
Magnet Material Ferrite
Overall Outside Diameter 103.5 mm
Overall Depth 56.4 mm
Baffle Cutout Diameter 85 mm
# Mounting Holes 4
Mounting Hole Diameter --
Bolt Circle Diameter --
Product Weight --