Dayton Audio ND91-4 3-1/2" Aluminum Cone Full-Range Driver 4 Ohm

Brand:| Model: ND91-4
Product Video
The low distortion and high excursion capabilities of the Dayton Audio ND91-4 3-1/2" full-range driver make it an ideal candidate for miniature point-source monitors, surround speakers, and line arrays.
  • 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
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Weight: 0.7 lbs.  
List Price$37.99
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Part # 290-224
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Product Details

Dayton Audio ND91-4 3-1/2" Aluminum Cone Full-Range Driver 4 Ohm

Dayton Audio's 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 ND90's voice coil diameter from 3/4" to 1" and adding a copper alloy shorting ring, the ND91-4 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 motor's 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.

Product Specifications
  • Nominal Diameter3-1/2"
  • Power Handling (RMS)30 Watts
  • Power Handling (max)60 Watts
  • Impedance4 ohms
  • Frequency Response65 TO 17,000 Hz
  • Sensitivity81.3 dB 1W/1m
  • Voice Coil Diameter1"
Thiele-Small Parameters
  • Resonant Frequency (Fs)63.4 Hz
  • DC Resistance (Re)4.1 ohms
  • Voice Coil Inductance (Le)0.74 mH
  • Mechanical Q (Qms)3.06
  • Electromagnetic Q (Qes)0.44
  • Total Q (Qts)0.38
  • Compliance Equivalent Volume (Vas)0.05 ft.³
  • Mechanical Compliance of Suspension (Cms)1.13 mm/N
  • BL Product (BL)4.6 Tm
  • Diaphragm Mass Inc. Airload (Mms)5.6g
  • Maximum Linear Excursion (Xmax)4.6 mm
  • Surface Area of Cone (Sd)30.4 cm²
Materials of Construction
  • Cone MaterialAluminum
  • Surround MaterialRubber
  • Voice Coil Wire MaterialAluminum
  • Voice Coil FormerKapton® / Polyimide
  • Basket / Frame MaterialSteel
  • Magnet MaterialFerrite
Mounting Information
  • Overall Outside Diameter3.35"
  • Baffle Cutout Diameter3.01"
  • Depth2.22"
  • # Mounting Holes4
Optimum Cabinet Size *
  • Sealed Volume0.01 ft.³
  • Sealed F3132 Hz
  • Vented Volume0.03 ft.³
  • Vented F373 Hz
  • * Enclosure volume/F3s based on BassBox "optimum" calculations-
Dayton Audio ND91-4 3-1/2" Aluminum Cone Full-Range Driver 4 Ohm
  • BrandDayton Audio
  • ModelND91-4
  • Part Number290-224
  • UPC844632090448
  • Product CategoryWoofers
  • Unit of MeasureEA
  • Product Rating
    (4 Reviews)
  • Weight0.7 lbs.
  • California Prop 65

    Warning: California residents only. Please note per Proposition 65 that this product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

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Dayton Audio ND91-4 3-1/2" Aluminum Cone Full-Range Driver 4 Ohm
Dayton Audio ND91-4 3-1/2" Aluminum Cone Full-Range Driver 4 Ohm is rated 4.25 out of 5 by 4.
Rated 4 out of 5 by from Competent DriverBought these to use as full range drivers for a tailgate box, crossed @ 125hz. Running 12 watts from a head unit, they put out surprising bass, obviously not ground pounding, but you hear bass that would be missed from a lot of other drivers this size. With the same 12 watts they're loud enough for most listening (except that one intoxicated cousin). According to my ears, they're lacking on the highs (expected from freq. response) and a bit bright, but all and all I'm satisfied with the purchase.
Date published: 2014-04-04
Rated 5 out of 5 by from Better than I had expectedI used this along with an 8w/ch amplifier board and the micro knockdown box to create a miniature bluetooth boombox. I'm only using one running off the left channel with my phone converting it to a mono signal, but wow. Even with just one of these little guys, like the other reviews have said, it's not 15" subwoofer shattering bass, but I can't get this amount of deep bass out of my 5 1/4" Polk bookshelf speakers.I've got the box tuned to ~45hz with lots of polyfill in it, and it will easily produce a solid 35hz tone using the tone generator. For the ports, I used two 6" sections of 3/8" ID tubing; I think it's meant for supplying water to freezers/fridges, but it was $.57 and works perfect. There is a bit of port noise when realllly pushing it, but I am genuinely impressed.The treble is a bit dull at first. Not bad, but not especially bright either. After about 10hrs break in, both the treble and bass have gotten stronger with a noticible increase in overall clarity. Using the tone generator, I was able to verify this does easily hit 15khz.When EQing, I boosted at 15hz, 62hz, 4khz, and 16khz; and dropped a dB or so at 1khz. I wish I had better EQ options but these work great. I'm ALMOST fooled that there is no tweeter (I'm a sucker for shimmering highs), the speaker handles a good amount of volume, and when corner loaded, you really would not be able to tell that there is no subwoofer. If you push the speaker too hard either when EQing or with sheer volume/power, you will hear it start to break up and muddy itself, it'll become pretty obvious that all the sound is coming from one over worked driver. At moderate to pretty loud (all things considered being a 3.5" full range) volumes, it sounds beautiful and unless you are sitting and really analyzing it, you won't miss the other 1 or 2 drivers that should be there.The speaker sounds great without an EQ, and amazing with an EQ. All things considered, even though I didn't expect this to perform like a dedicated sub, midrange, and tweeter, it does a surprisingly good job, even moreso considering the price.
Date published: 2014-03-29
Rated 4 out of 5 by from A repair for my Logitech Squeezebox BoomI replaced a pair of failed drivers with the ND91-4s. This was based on an idea discussed in the Squeezebox Wiki. Quite a job to modify the new drivers and the enclosure to get the fit just right. But wow... was it worth it. The sound quality of the Squeezebox was restored as good as new. Thanks Wiki... thanks Dayton Audio... thanks Parts Express!
Date published: 2014-03-29
Rated 4 out of 5 by from Big sound from a small driverA pair of these are mounted in a small transmission line enclosure boombox. Paired with a wee Lepai amp, they put out plenty of volume and with surprising bass capabilities. Since they are Klippel optimized, there is no need for any filtering/crossover components, and bit of EQing with the bass/treble knobs on the amp makes for a nice, full-range sound. Don't expect to shake any walls, but these lil' suckers will surprise you. One caveat, since the connection tabs are adjacent to the mounting corner, be careful with your cutout. Also, a healthy chamfer is a necessity on the back of your baffle.
Date published: 2013-09-26

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Dayton Audio ND91-4 3-1/2" Aluminum Cone Full-Range Driver 4 Ohm

Power requirement

Would a DTA 2 be powerful enough for this?
Asked by: SeeJ333
The DTA-2 would be a perfect match for this driver.
Answered by: MattP
Date published: 2012-12-26

What would be a good box volume and port size/length for 2 of these drivers in the same enclosure?

Asked by: benfong31
I would recommend .26 cubic feet with a 1.5" diameter, 4" long port for a tuning frequency of 55 Hz.
Answered by: MattP
Date published: 2014-03-12

2 of these in series per channel high pass at 125 Hz.  Since I'm not going to use these for sub frequencies, what would be a good enclosure? sealed/ported? size?  They'll be in a boombox (2.1 plate amp).  25 watts RMS per set of ND91-4 3 1/2s.  Thanks!

Asked by: benfong31
With that kind of power the box volume wont make much difference. Sealed will easily get you to 125 on the bottom end and you won't have any excursion problems.
Answered by: MattP
Date published: 2014-03-13

ND91-8 3 1/2 Response: " would recommend 0.128 cubic feet with heavy fill and use a port that is 1" in diameter and 4" long. This will tune the enclosure to 55 Hz and with room gain will provide a nice flat response." Same for the ND91-4 3 1/2?

Asked by: benfong31
Yes this will also work with the 4 ohm model.
Answered by: MattP
Date published: 2014-03-13

Does Dayton (or anyone else) make a hight quality 2 1/2" speaker rather than 3 1/2"? I'm looking for a speaker for a cigar box guitar amp.

Asked by: Peter P
Such things do exist, indeed. Please see the items I've linked below for your convenience, and this category in general:http://www.parts-express.com/wizards/searchResults.cfm?srchExt=CAT&srchCat=576Browse through the selection we have, I'm sure you can find something suitable for your application.
Answered by: RussR
Date published: 2012-01-16

are these suitable for tl enclosure? if so could you give me a idea of length

Asked by: lusty smalls
I am by no means a T-line guru, but I have a pair mounted in a long enclosure used as a boombox. The line length is just over 4 feet (~1.4m) with an 8:1 taper with the terminus area a little less than Sd. I have not measured any frequency response, but there is solid bass at least to 60Hz. Take all of these tidbits as pure subjective impressions, though.
Answered by: LoveMachine
Date published: 2014-03-29


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