Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier

Brand:| Model: SPA250
Product Video
Engineered to provide flexibility, ample power, and reliability, the Dayton Audio SPA250 delivers high fidelity subwoofer amplification and is tailored for home audio and home theater audio systems.
A restocked/refurbished, or Open Box unit of the product is available -- see it now
  • Switchable 6 dB @ 35 Hz bass boost
  • Mono Class AB output stage for solid, well defined output
  • Low-level and high-level inputs connect to any system
  • Manual, auto, or triggered on/off modes for compatibility with any automated system
  • Variable gain, crossover point and switchable phase controls optimize room integration
  • Switchable 120/240V input voltage
  • Energy efficient—draws less than 1 watt in stand-by mode
Part # 
Weight: 13.4 lbs.  
Regular Price$124.80
Sale Price
Part # 300-803
Qty:  EA
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Product Details

Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier

The Dayton Audio SPA250 subwoofer amplifier produces 250 watts of clean power output, and combines with a host of flexible user options to make it an unbeatable choice. A user-configurable bass boost circuit creates a 6 dB peak at 35 Hz, which allows sealed subwoofer designs and certain ported enclosures to achieve their optimum bass extension and maximum "flat" output.

The SPA250 features RCA line level and banana jack speaker level inputs and outputs, automatic power-on that is triggered by any audio input signal, and a phase reverse switch to match the subwoofer to your room and your other speakers. A single amp can accept a stereo input signal and combine it into mono, which is preferred for sub bass reproduction. A preamp or receiver's LFE output may be connected to the SPA250's Left (mono) input. The internal low pass crossover is fully adjustable between 40 and 180 Hz, and of course the amp has built-in protection against internal and external faults.

• Variable low-pass filter at 24 dB/octave attenuation from 40 Hz ~ 180 Hz
• Switchable phase 0° (NOR) or 180° (REV)
• Variable gain MIN/MAX input voltage dependent
• Speaker level high-pass outputs 6 dB/octave at approximately 180 Hz @ 4 ohms, 90 Hz @ 8 ohms (i.e. 220 uF electrolytic capacitor)
• Line-level full bandwidth (10 Hz- 20 kHz) outputs/throughputs for adding or "daisy chaining" additional amplifiers
• Subsonic filter 12 dB/octave high-pass filter centered at 20 Hz
• Damping factor at rated power: 114 @ 100 Hz

Specifications: • Measured power output: 156 watts RMS into 8 ohms @ 0.1% THD, 252 watts RMS into 4 ohms @ < 1.0% THD • Signal to noise ratio: 90 dB A-weighted • Input impedance: 10.4K ohms • Bass boost: Switchable, 6 dB @ 35 Hz • Low pass adjustment: 40 Hz to 180 Hz • Phase adjustment: 0º (normal) 180º (reverse) • Power requirements: Switchable, 115/230 VAC, 50/60 Hz • Dimensions: 9-13/16" W x 9-13/16" H x 5" D • Cutout dimensions: 8-1/2" W x 8-1/2" H.

Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier
  • BrandDayton Audio
  • ModelSPA250
  • Part Number300-803
  • UPC844632094897
  • Product CategorySubwoofer Plate Amplifiers
  • Unit of MeasureEA
  • Product Rating
    (129 Reviews)
  • Weight13.4 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 SPA250 250 Watt Subwoofer Plate Amplifier
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Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier
Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier is rated 4.5504 out of 5 by 129.
Rated 5 out of 5 by from What a difference this amplifier makesMy pasive DBX subwoofer has come back alive after 25 years.This subwoofer was build like a rock and worked for years being driven by the main amp, but adding this subwoofer amp has turned the 15" double spool woofer in a woofer that shakes the room when turning up the volume.Highly recommended.
Date published: 2014-12-14
Rated 5 out of 5 by from Amp for Velodyne 3750My Velodyne amp died and this was the perfect choice! This plate amp is well made with a real quality feel to the control knobs, etc. I installed this in my Velodyne 3750r and it fit like a glove!! All 12 mounting holes lined up for an easy installation. Listened to it for an hour last night and I'm very pleased, this amp has more power than the original! Can't wait to listen to the next Blu Ray movie in DTS 7.1!! Awesome product!
Date published: 2014-12-02
Rated 5 out of 5 by from Replacement Amp for Velodyne 3750RInstalled this amp last night and I'm amazed with this product. From shipping, packing to installation. All the mounting holes lined up exactly, you would have thought it was made for the Velodyne 3750. All the controls have a quality feel to them. This Amp drives my sub better than the original amp and I can't wait to watch a blu ray with the kiddo's and shake the living room again!! Great Product!!! 5 Stars!
Date published: 2014-12-02
Rated 1 out of 5 by from NoisyBought this and tried as a replacement for my outlaw LF1. Sounded muddy compared to original. After about a day unit started making random thumps even when uuplugged from the receiver. Hooked up a second sub to check if it was the incoming power and no issue with that sub. contacted tech support and returned. Great return policy from Parts Express! just disappointed in the Dayton product.
Date published: 2014-11-21
Rated 5 out of 5 by from More Than SatisfiedI can't give this amp enough compliments. I bought this because I have wanted a new sub for years and I figured it is dumb to pay $400 for a big name sub when I can make a better one for less than half the price. After I read the reviews I knew this would be the one for me. I even got it with a $10 discount with a code I found online. I used birch plywood, a JBL 12" 275w RMS sub I found for $29 (regularly priced at $79), and for $174 I have sick lows that pound the floor. It hits so hard that on the test run it had my brother's HK sub moving across the floor on every bass beat. It has options for hookup a nice beefy heatsink and solid design. The worst thing I can say about this amp is if the volume on your receiver is very low the auto on feature may not work properly. I just leave the switch in the "on" position and turn it off if the receiver isn't being used. No need at all for the bass boost feature; this amp is more than ample without it. I would definitely buy one of these again.
Date published: 2014-11-20
Rated 4 out of 5 by from Dayton SPA250 Plate AmpI did quite a bit of research and decided on the Dayton SPA250 for my home-built subwoofer enclosure. After 23 years of using a DBX 150 Mono-Block subwoofer amplifier and one repair bill it didn't owe me a thing. It was time to either have it repaired again or replace it. I've had it connected for a few days and played it twice so far and I'm liking it. I've read about people having issues and replacing certain resistors but for the cost of this unit and the fact that I don't play it that often, I'm hoping it will last for several years. Now that I have a working amp again, it will be most likely be played more often. The bass boost circuit is in an inappropriate location because once mounted in the enclosure that's all you get. If it was top mounted, it could be an easier access. The original cardboard shipping carton was of poor construction and when shipped by you, it was only put in a larger box with hardly no packing material. The Dayton owner's manual isa two page document with no hook up diagram but wasn't an issue due to it being a replacement.
Date published: 2014-11-12

Product Q&A

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who own this product or have experience with it.
If your question requires design or troubleshooting information,
please email tech@parts-expresss.com  for a prompt reply.
Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier

Do I have to use the "plastic box that comes with this amp, or can I use the exisiting one that is still part of the KLH S200ETH? I am having trouble finding another amp that will fit the opening and plasticbox that already exists?

Asked by: jackce57
Removing the case on the back side of the amp is not recommended since this seals the plate from air leaks. as long as the amplifier is sealed to the cabinet you can use either case, just be careful removing the one that is on the amp.
Answered by: MattP
Date published: 2014-12-17

Hello I was wondering if you could help me I have a Infinity BU-80 100 watt and the amp went out and did not know if you would recommend this plate or another to fit it properly and to make sure it would not be to much power to the subwoofer.

Asked by: fatboy33

I finally put together my Dayton SA100 amp with my Clarksynthesis TST209 transducer in my couch. My issue is when I turn my music up (not as loud as I usually listen to it) the transducer will work for a few minutes then cut out or turn off. HELP

Asked by: Radiojunkee
Please contact our tech support for more help with this question, tech@parts-express.com or 800-338-0531 x1.
Answered by: MattP
Date published: 2014-12-11

MattP, Thanks for your answer. Would it be preferable to go with this plate amp or should i consider the Dayton Audio SA230? Please forgive the simple questions, i am very new to all of this. RC Driver

Asked by: RC Driver
Either amp will give you very similar performance so the choice is up to aesthetics. The SA230 would probably fit in better if it was included with the rest of your equipment, although it is up to you as to whether that will justify the price difference.
Answered by: MattP
Date published: 2014-12-05

Is it possible to mount a plate amplifier near my other components and run the speaker wire to my in-wall subwoofer? The run is 35 feet thru walls and ceiling. Thanks.

Asked by: RC Driver
Yes, this is a very common thing to do. As long as you provide some breathing room for the heat sink, you can mount this amplifier basically anywhere (indoors).
Answered by: MattP
Date published: 2014-12-05

I have a Sony SA-WX700 that has two 10" 6ohm woofers. Will this amp work for this application? I'm guessing it's not recommended to wire in parallel as that would put my ohms at 3 but wiring in series would result it 12ohms correct?

Asked by: Neilybob88
Yes this amp will work, but you are correct. I would only recommend wiring the woofer to 12 ohms to provide a safe load on the amplifier.
Answered by: MattP
Date published: 2014-12-05


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