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Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier

Brand:| Model: SPA250
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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.
  • 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.  
List Price$199.99
You Save37%
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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 90 Hz @ 4 ohms, 180 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
    (103 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 4.5922 out of 5 by 103.
Rated 5 out of 5 by from Very good performance for the priceI just installed this in an old JBL powered sub as the original JBL amp died. I had to do a little woodworking to make it fit but it works great and seems like a very good price for the performance you obtain. Brought my old JBL back to life. Thanks Parts Express!
Date published: 2014-04-16
Rated 4 out of 5 by from Very Good ValueThis product is performing as advertise. Great bass sound and very easy to install.
Date published: 2014-04-14
Rated 5 out of 5 by from Better than original equipmentThis Amp rocks, replaces my Infinity Entra non working amp, I had to modify cabinet a little but it sounds better than new.
Date published: 2014-04-05
Rated 5 out of 5 by from Perfect Fit for Sound Bridge 12SBX1.5The amp in my Sound Bridge 12SBX1.5 died over a year ago, and I finally got around to looking for a replacement. The wattage, dimensions, and cut-out size perfectly matched this amp, and the sub sounds as good as it ever did.I did not enable the bass boost since the sub drops off around 40 Hz and there's considerable port noise when pushed.
Date published: 2014-04-01
Rated 2 out of 5 by from Thumping sounds - very laudIt started to make random loud thumping sounds after a year, that scares you big time since you were not expecting it. I don't mind turning it off when not in use but it also makes the same noise while music plays too, not good. It also defeats the purpose of auto on/off. This happens whether it is connected to the rest of system or not. Don't want to get another one since it maybe more waste of money, need to find another replacement plate amp. It was purchased on October 2012 and started to make the sounds late 2013.
Date published: 2014-03-31
Rated 4 out of 5 by from Great replacementI purchased this plate amp to replace a defective amp on a Legend Audio 12" subwoofer. The amp works great with so far with one week's usage and fit the factory opening. No hum or noise so far. I am a satisfied customer.
Date published: 2014-03-25

Product Q&A

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Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier

Dayton sa 250 poor volume

I recently purchased this unit, It has poor volume. I AM USING IT WITH A 12 INCH CAR SPEAKER DVC rated @ 6 ohms eachI am useing only one voice coil, can I paralell the voice coilsmakeing it three ohms, will it hurt the AMP.main problem is poor volume,What 12 inch speaker would be best from Parts ExpressThank You HERMAN43
Asked by: pipejoint
You should use a proper driver in the correct enclosure to get optimum performance from this exceptional amp. Car speakers, with some exceptions do not translate at all into home environments - they were created for small vacuous mobile spaces... in the search bar - search "subwoofer kits" and you can see some prepackaged options that work with your amp. You can buy the cabinets and drivers separately, or just the driver and make your own cabinet.
Answered by: MarkAJH
Date published: 2014-02-05

Can you Daisy chain the high level in/outs?

On the manual it states that you can daisy chain the low level in/out. Will it apply if you daisy chain the in/out put for the high levels?
Asked by: maxpowers
If you intend to speaker out from a source and then parallel the inputs of several plate amps, then yes you can.
Answered by: Nitnub
Date published: 2014-01-01

Low Level input: Connect (L) only, or (L+R)?

According to the manual:-------------------------------------------------------------------------"1.) Low-Level Inputs (Left/Right)RCA style jacks that will accept standard line level inputs froma pre-amp level source. They will accept a stereo signal andinternally combine it into mono. Both left and right input jacksmust be connected to the source in order to drive the amplifierto full output. Note: If using a LFE output from a preamp orreceiver connect it to the Left (mono) input."-------------------------------------------------------------------------So, if I am connecting from my Receiver's single LFE output, and connect to the low level (L/Mono) input only as per instructions, would I only get 1/2 power from the plate amp? Im confused because first it says connect BOTH to get full power, but then it says connect only 1 (L/Mono) if using LFE signal.
Asked by: Cris
Using L+R input is designed for people using an electronic crossover. Each input is designed to match that application. When you use an LFE output - that signal is larger, and plugging it into the Left/mono input will provide you with full output power.
Answered by: MarkAJH
Date published: 2014-03-31

Are the pictures correct?

Are the pictures correct? They seem to be the same as in SA240 and there's no LFE jack on picture. On Dayton's webpage there's no SPA250 on their catalog.
Asked by: marsellago
Yup. NO LFE hi or lo input contrary to the description...good catch.PE usually does a good job to ensure accuracy in their photos...PE?
Answered by: Fanden
Date published: 2014-01-01

Could you please suggest a good 12inch subwoofer to suit my spa250 plate amp thankyou

Asked by: Kfrahm
The Dayton RSS315HF, RSS315HO and TIT320 should work well with that amp, also the Eminence LAB 12 would be a good choice as well.
Answered by: mtg90
Date published: 2013-05-06

Issues with noises while not in use

I've actually purchases two of these. One for myself and one for a subwoofer for my father-in-law. Mine is having the issue that when not in use and powered for some time I start to hear a lot of static and low frequency humming. The longer left the more intense the noise. I've tried disconnecting the inputs, turning down the volume and turning the amp to off with no luck. The only thing that eliminates it is unplugging the amp. I haven't heard this first hand on my Father-in-laws unit, but he did call me once saying that it was making a lot of weird noises and I told him to just unplug it. I doubt that he's plugged it back in since he doesn't watch a lot of TV. Just wondering if anyone has experienced this, or if I have something wired up wrong.
Asked by: Djstevens
It would be odd if both units experienced the same problem. The most obvious things to start with are to plug the plate amp into a different electrical circuit in your house. There may be a motor, AC or some other source of noise on that circuit. The other is to replace the RCA cable from your pre-out/LFE out etc to the sub in. The longer the run - the more important the shielding is. And DON'T run it parallel to electric wires, extension cords etc - that acts like an antenna to pick up noise. If those things don't work - you may have internal problems with your amp. Typically - it's what I mentioned abovel
Answered by: MarkAJH
Date published: 2014-02-05


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