Dayton Audio SPA250 250 Watt Subwoofer Amplifier
Dayton Audio SPA250 250 Watt Subwoofer Amplifier

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Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier

Brand:|Model: SPA250
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.
In Stock
Regular Price$139.80
Sale Price
Dayton Audio Baseball Cap
Qty: 1Part # 520-308
List Price:$19.99
Part # 300-803
  • 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

Product Details

Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier

Bass boost or flat…you choose and the SPA250 delivers!

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.

Connects to almost any home audio system, and does it with ease

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.

We haven't run out of great features to talk about

• 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
    (153 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 4.4641 out of 5 by 153.
Rated 5 out of 5 by from Sounds Great!I bought this amp several years ago. I have two small satellite spekers and use this to fill in the lows. Currently hooked up to a JL Audio 10" Sub in a sealed enclosure. It works great and has plenty of punch for the music we listen to.
Date published: 2015-08-18
Rated 5 out of 5 by from Pefect drop in replacment for KLH SubI purchased this from a parts express eBay listing to replace the burnt up amp in my old KLH subwoofer fit perfectly even the screw holes lined up. Its been years since I listened to the sub in new condition the sub sounded dull and shoddy for some time before it burnt out but I am certain it sounds better than when I bought it new, been using it for a couple of months now no issues.
Date published: 2015-07-15
Rated 4 out of 5 by from Nice Plate AmpI'll start off with the review stating that the first one I received was DOA. As soon as it was plugged in it started to hum threw the speaker outputs fairly loud even switched to the "Off" position. The humming would reduce once switched to "On". I tried playing music through it even with the humming and the bass was completely distorted. Note that this amp had no bass boost switch and didn't have the computer style plug in power cord. It was a cord that was wired to the unit. (The one pictured below, note that I don't have a picture of the one that wasn't DOA)Now the second unit I received was as expected. (I should note that PE's customer service is very good. Some of the best customer service I have had from a website.) No noise while no music was being played. The auto turn on works as expected. This one had the computer style power cord and the bass boost switch, which is rather comical where it is placed. If you have your cut out for the plate amp on the box fairly snug, the cap for the bass boost will get in the road. You'll have to pop it off before you insert the amp and then put it back on once the amp is mounted. It has great output. I should go and test to see its true wattage with my AMM.1. If I do I will comment onto this review. It does get a bit warm when I was playing music with heavy bass lines in it. But it stays luke warm when watching movies. In the end I am pleased with the unit now that I have one that is functional. It would receive 5 stars if I didn't get a defective one off the batt.
Date published: 2015-06-29
Rated 1 out of 5 by from Excessive mechanical and electrical hum.I bought this am to work with a SB Acoustics 12" subwoofer. I found the amp to have excessive transformer mechanical hum clearly audible across the room and the electrical hum and hiss that comes through the speaker is excessive as well. In addition the bass boost switch cracked off the pc board when I tried to slide it. Both the owners manual and the amp are unmarked as to which position is the boost position. I had to remove the switch and solder jumpers. The PC board is marked for position. Complete junk for any audiophile application.
Date published: 2015-06-08
Rated 5 out of 5 by from Replacement for SA70 amplifier in KLH SubwooferThe gain control on the amplifier in my ten-year-old KLH ASW10-100C subwoofer stopped working. Another reviewer recommended replacing the amplifier with an SPA250 (250 watt). Turns out the original amplifier in the KLH subwoofer was an SA70 (70 watt). I just had to enlarge the amplifier mounting hole in the subwoofer case. The SPA250 fit right in. Unfortunately, when firing it up to test it, I got a lot of "pops" and even a "falling bomb" sounds. Called Technical Support and the Technician diagnosed an improperly set Bass Boost Switch. He said the access hole plug when inserted sometimes moves the PC board switch "off" its correct position. This turned out to be the case, and the "fix" was very quick. The KLH with the SPA250 has worked flawlessly since. Just have to be careful with the gain control setting, as the new amplifier is several times more poweful than the original. Very happy with the purchase, and Parts Express Technical Support.
Date published: 2015-05-16
Rated 1 out of 5 by from Not so goodHad this amp for couple years of light duty driving 2 peerless 10 inch subs then, poof! never played it past half gain. disapointed.
Date published: 2015-03-28
  • 2015-09-02T07:02CST
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  • cp_1, bvpage1
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  • loc_en_US, sid_300-803, PRD, sort_mostRecent
  • clientName_PartsExpressInternational

Product Q&A

Get your questions answered from other customers
who own this product or have experience with it.
If your question requires design or troubleshooting information,
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Dayton Audio SPA250 250 Watt Subwoofer Plate Amplifier

Best replacement subwoofer plate amplifiers for a JBL PB10?

Asked by: JerryNJ
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: 2015-08-26

The sub i have has a dual 6.5 ohm coil. So if i run it parallel it ends up at 3.5 ohms, and if i run it in series it ends at 12.5 ohms. would it be safe to run it parallel? If not would it be safe to run at 12.5 ohms? (design acoustics ps sw subwoofer)

Asked by: aron304
Wiring those coils in parallel will not harm this amplifier. A DCR of 6.5 ohms is very common for an 8 ohm coil.
Answered by: MattP
Date published: 2015-08-31

150 watts 20 hz - 200 hz are the specs for an M & K MX 125 sub that I have. Will this plate work?

Asked by: harmony08
As long as the woofer is 4 ohm or higher and you can modify the cabinet cutout if necessary, this amplifier will work fine.
Answered by: MattP
Date published: 2015-08-17

Just bought a Dayton Sub1200 could i use this amp in the sub and is it play and play?

Asked by: zeno312
Please contact our tech support for more help with this question, or 800-338-0531
Answered by: MattW
Date published: 2015-08-10

Hi,I wondered if this amp would fit my subwoofer.Its a Jensen QX-90,which appears identical except that the gain and  frequency controls are on the front of the subwoofer.Could this be fitted and gain and frequency adjusted on the amp instead of the front

Asked by: pauly5360
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: 2015-07-07

Hi, dose this one fit my CLS-15S cerwin-vega or not? Thanks.

Asked by: Thavro
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: 2015-07-02
  • 2015-09-02T07:58CST
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