Dayton Audio ST305-8 12" Series II Woofer

Brand:|Model: ST305-8
The new generation of Dayton Audio Heavy Duty woofers features natural sounding paper cones that are chemically treated for extra durability and long life. The ST305-8 12" Series II woofer is suitable for pro or home audio subwoofer use.
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List Price$129.99
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Part # 295-120
  • Natural sounding paper cones that are chemically treated for extra durability and long life
  • Consists of a rubber surround and large flat spider for superior damping
  • Feature a large magnet structure
  • Made in USA

Product Details

Dayton Audio ST305-8 12" Series II Woofer

The Dayton Audio ST305-8 Series II heavy duty 12" woofers feature a large magnet structure, vented pole piece, bumped backplate, and large voice coil. This combination provides excellent power handling capability, high efficiency, and very low distortion. The ST305-8 speaker's suspension system consists of a rubber surround and large flat spider for superior damping characteristics and outstanding transient response. Made in the USA.

Product Specifications
  • Nominal Diameter12"
  • Power Handling (RMS)275 Watts
  • Power Handling (max)550 Watts
  • Impedance8 ohms
  • Frequency Response25 to 2,000 Hz
  • Sensitivity92.2 dB 2.83V/1m
  • Voice Coil Diameter2.51"
  • Magnet Weight56 oz.
Thiele-Small Parameters
  • Resonant Frequency (Fs)26.2 Hz
  • DC Resistance (Re)6.2 ohms
  • Voice Coil Inductance (Le)3.62 mH
  • Mechanical Q (Qms)7.50
  • Electromagnetic Q (Qes)0.35
  • Total Q (Qts)0.34
  • Compliance Equivalent Volume (Vas)5.79 ft.³
  • Mechanical Compliance of Suspension (Cms)0.42 mm/N
  • BL Product (BL)15.9 Tm
  • Diaphragm Mass Inc. Airload (Mms)87.2g
  • Maximum Linear Excursion (Xmax)8 mm
  • Surface Area of Cone (Sd)506.7 cm²
Materials of Construction
  • Cone MaterialCoated Paper
  • Surround MaterialRubber
  • Voice Coil Wire MaterialCopper
  • Voice Coil FormerKapton® / Polyimide
  • Basket / Frame MaterialSteel
  • Magnet MaterialFerrite
Mounting Information
  • Overall Outside Diameter12.03"
  • Baffle Cutout Diameter10.95"
  • Depth6.25"
  • Bolt Circle Diameter11.59"
  • # Mounting Holes8
Optimum Cabinet Size (determined using BassBox 6 Pro High Fidelity suggestion)
  • Sealed Volume1 ft.³
  • Sealed F368 Hz
  • Vented Volume2.52 ft.³
  • Vented F341 Hz
Dayton Audio ST305-8 12" Series II Woofer
  • BrandDayton Audio
  • ModelST305-8
  • Part Number295-120
  • UPC844632000041
  • Product CategoryWoofers
  • Unit of MeasureEA
  • Product Rating
    (44 Reviews)
  • Weight15.33 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.

View similar products to the Dayton Audio ST305-8 12" Series II Woofer
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Dayton Audio ST305-8 12" Series II Woofer
Dayton Audio ST305-8 12" Series II Woofer is rated 4.4318 out of 5 by 44.
Rated 5 out of 5 by from Great woofers.I replaced the old Infinity RS 2.5 woofers with these speakers, and I have to say they sound as good or better than the originals did.Parts Express is THE place to shop for replacement parts, or parts for your builds.
Date published: 2015-10-02
Rated 5 out of 5 by from VERY DEEP BASS!!!!I gutted an old pair of Electro-Voice "Encore 77's" and replaced everything with parts I got from Parts Express. Here's a picture of my "Franken-Speaker". I'm using an Eminence crossover, a Dayton AMT mini, a Dayton 2" dome mid and the ST305-8 woofer. The sound I'm getting through these speakers is stellar. I chose components that could handle lots of power as I'm using a Carver M1.5t to drive them to concert volume levels. And yet when playing "Vangelis", the strings and piano are sweet as audible honey. I would easily compare them to speakers in the 2,000$ range. Parts Express sells the best components for DIY'ers like me, and the results are awesome.
Date published: 2015-05-17
Rated 5 out of 5 by from Very Impressed!I've replaced 2 blown woofers in my satellite speakers,when I first powered these they sounded excellent I thought and was so happy,that was almost 5 yrs ago being powered bya a crown xls 802 and still sound as good as they did the day I bought them,Thanks parts my order came fast packing was excellent except for 1 woofer was bad,parts express no question asked replaced the bad one,kudo's parts express and have bought a 80hz low pass filter from them also,my 18 inch sub sounds tight!..Thanks...
Date published: 2015-02-08
Rated 5 out of 5 by from Great sounding speakerPlays awesome, would recommend this to my friends, great to play outdoors on my deck.
Date published: 2014-07-01
Rated 4 out of 5 by from Decent woofer for the money.I bought these woofers to replace the ones in my home built 3-way speakers built in the 90s. One of the original Nippon 12" woofers was bad (voice coil scuffing). So I used these Dayton ST305-8 as replacements. They have plenty of bass and handle plenty of power as I am powering them with my vintage Adcom GFA-1amplifier. They do have a slightly different response than my old Nippons (a little peaky) but overall I am satisfied.
Date published: 2014-05-08
Rated 5 out of 5 by from So Helpful!When a woofer in my very expensive Genelec 1037a speakers failed because the form surrounding it didn't like the humidity here in Hawaii I wasn't sure where to turn. The Genelec factory had no replacement parts and no suggestions. Parts Express discussed the specs with me and these woofers have done a terrific job getting my Gelelec's back into my recording studio. Thanks!
Date published: 2014-04-09
  • 2015-11-27T06:21CST
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Product Q&A

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Dayton Audio ST305-8 12" Series II Woofer

would this be a good upgrade for my paradigm pdr12 subwoofer?

Asked by: Buddyroe1
We do not have a cross reference available for this type of thing. Please contact our tech support for more help with this question, or 800-338-0531 x1.
Answered by: MattP
Date published: 2015-11-24

hi, what is the volume of the driver , i mean how much space does the driver fill in the cabinet ? i would need that to calculate box volume .

Asked by: mdrb
The displacement of this woofer is 0.11 cubic feet.
Answered by: MattP
Date published: 2015-04-29

can I replace a set of klipsh heresy k-22 woofers with the st305-8 12" I can't find info on crossover freq. or woofer impedance of k-22's

Asked by: jaguar jak
Please contact our tech support for more help with this question, or 800-338-0531 x1.
Answered by: MattP
Date published: 2015-04-14

These drivers are the perfect match for a project I am drafting. However the gasket looking material on the frame doesn't suit me. Is this material relatively easy to remove? 

Asked by: jparmeley91
The gasket on this woofer is a laminated cardboard/paper type and can be relatively easy to remove if this is something you would like to do. Be careful not to cut the surround.
Answered by: MattP
Date published: 2015-03-02

Can these speakers run off a 4 ohm load in an 8 load cabinet powered from drown xls 802 amp ?

Asked by: Frankie 8
Please contact our tech support for more help with this question, or 800-338-0531 x1.
Answered by: MattP
Date published: 2015-02-11

Is one cu.ft. really the best sealed cabinet size for one of these? How would sound be affected by increasing cabinet size by 50% to one and a half cu.ft. This would be for music and h/t use. Music being most important. How can I contact mainland?  

Asked by: BW28
Increasing the volume to 1.5 cubic feet will drop the Qtc to .585 and slightly lower F3 to 69 Hz. These will really work best in a ported design if you want decent bass from them. A sealed box will only have useable output down to about 40-45 Hz.
Answered by: MattP
Date published: 2015-01-05
  • 2015-11-27T06:49CST
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