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Dayton Audio SPA500 500W Subwoofer Plate Amplifier

Brand:|Model: SPA500|Part # 300-807
The Dayton Audio SPA500 Subwoofer Amplifier delivers the efficiency of a Class-D design, without compromising audio quality and reliability.
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Regular Price$285.50
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Part # 300-807
  • High power Class-AB output stage for clean, controlled output
  • Patented tracking downconverter power supply for high efficiency
  • Toroidal power supply transformer
  • Low frequency parametric EQ allows you to boost or cut to custom-tailor sound
  • Advanced soft clip circuitry improves headroom and protects woofers
  • OTC™ (Optimized Thermal Circuit) protects amplifier from potential heat damage
  • Hercules heat sinks dissipate and control heat for extreme reliability

Product Details

Dayton Audio SPA500 500W Subwoofer Plate Amplifier

One of the most technologically advanced subwoofer amplifiers on the market today! The Dayton Audio SPA500 subwoofer amplifier is based on a state-of-the-art Class-G circuit topology that combines the proven high power, high fidelity characteristics of a Class-AB amplifier with a patented tracking down converter power supply to achieve an operating efficiency up to 86%. You get the efficiency of a Class-D amplifier without compromising audio quality and reliability. The Class-AB output stage provides the clean and low-distortion sound that audiophiles demand, without any of the instability problems that plague other high-efficiency amplifier designs.

This American-designed and engineered amplifier uses patented circuitry that continuously tracks the input signal to modulate or control the voltage available to the output stage. This "tracking" capability delivers the exact amount of power based on demand instead of constantly keeping it in reserve, so the output stage only draws the amount of power that is required at any given time. Less energy is wasted as heat, and more power is available for the subwoofer driver. With its enhanced thermal management, the SPA500 is an upgrade over previous models—making it a nearly bulletproof amplifier choice for today's demanding HT audio and music playback applications.

Specifications: • Rated power output: 273 watts into 8 ohms, 540 watts into 4 ohms with 0.92% THD (based on one-third power duty cycle) • S/N ratio: 98 dB (A-weighted) • Low-pass crossover: 30 - 200 Hz, 24 dB/octave • Input voltage: User switchable 115/230V (Euro cord available) • Dimensions: 11-15/16" W x 11-15/16" H x 5-1/4" D; Cutout dimensions: 10" W x 10" H.

Dayton Audio SPA500 500W Subwoofer Plate Amplifier
  • BrandDayton Audio
  • ModelSPA500
  • Part Number300-807
  • UPC844632015922
  • Product CategorySubwoofer Plate Amplifiers
  • Unit of MeasureEA
  • Product Rating
    (40 Reviews)
  • Weight20 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.


Dayton Audio SPA500 500W Subwoofer Plate Amplifier
Dayton Audio SPA500 500W Subwoofer Plate Amplifier is rated 4.175 out of 5 by 40.
Date published: 2015-10-11
Rated 5 out of 5 by from Produces an exceptional bass soundThe sound this Amp produces with the speaker it drives and box it's installed is of the highest quality. A truly "SWEET" ultra-tight undistorted bass, which even with over 3/4s gain does NOT make the windows or any other object vibrate in the room. Yet it is producing massive amounts of 30-minus Hertz signal, which if played through most other types of Subwoofer drivers would shake the foundations of the room.This amp coupled with the 13inch Scan-speak Revelator produces real TEXT BOOK quality clear TIGHT bass. I have never heard anything like it before.Amazing stuff.
Date published: 2015-06-29
Rated 5 out of 5 by from Amp mated to an Ultimax 10" in a ported boxI needed to add mechanical resistance with too much poly fill because it was clipping during a test fit. Now it provides enough power to extend down to 20Hz. The software heard it to 17Hz, after calibration. I have not used the EQ on the amp because I do it at the preamp. If I did not know how to wrangle it's power it would seem like a bad amp, it is just wild and needs control
Date published: 2015-05-15
Rated 1 out of 5 by from Exaggerated SpecsThis amplifier isn't what it seems. At first glance, the power to price ratio seems reasonable until you read the fine print about the amplifier producing its rated output at 1/3 duty cycle. At four ohms, this amplifier produces nearly half of its rated output at acceptable distortion levels, continuously. In addition, the auto on circuit is poorly designed as it requires around .5 volts of input signal to activate. This amplifier also produces excessive turn on thump when the auto on threshold is reached. The manufacturer could have added a second relay that decouples the output stage, but they didn't spend the extra time or money in the design process.
Date published: 2015-04-08
Rated 3 out of 5 by from Bogus Companybought sp 500 and cant get it fixed. company said its cost prohibited. and they wont send schematic even if I pay.
Date published: 2014-12-12
Rated 3 out of 5 by from 8 months of great bassAs the title states, bought this amp to replace the trouble plagued plate amp in the MFW-15. I was very happy with the upgrade I made with 500 watts from 300. Sadly, she popped at a moderate volume level while watching The Legos Movie.
Date published: 2014-08-03
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Product Q&A

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Dayton Audio SPA500 500W Subwoofer Plate Amplifier

Can I get a copy of the schematic for the input and output, I have a few bad resistors and can not make the color codes to find the tolerance or values. I have a SPA500 500watt amp same as above just a little older the version is rev:1.

Asked by: Shiftygt
I am sorry, we do not have schematics available for Dayton amplifiers.
Answered by: Chrisf
Date published: 2016-04-15

I have a single 12 inch Kenwood Subwoofer with a peak of 1000w that I have been trying to use to the fullest of its capabilities with no success thus far. Will this plate amp be enough power to get the most from my sub?

Asked by: Zachary13
This amp should be an excellent choice for that type of driver.
Answered by: Chrisf
Date published: 2016-03-11

I recently built a pr. of subs each using a SPA500 amp. Preamp has two sub outs. Intention is to have one sub play the right and the other play the left channel. Question - should I use the Left and Right inputs on the amp with a splitter, or the LFE?

Asked by: Craig A
Chances are the outputs on the receiver are mono anyway, not left and right. I would use the LFE regardless and use the crossover on the receiver.
Answered by: MattP
Date published: 2016-03-02

I have an older MTX SW 115 sub w/remote, I think the amp is blown, would you have a replacement amp for this older sub?

Asked by: BigMack
We do not have a direct drop in replacement for this, but if the amp's mounting dimensions are the same, then this will certainly drive it.
Answered by: Chrisf
Date published: 2016-03-16

I made 2 of the DIY 3.0 cubic foot boxes each with the Dayton 15" HF 4ohm and each with this plate amp mounted.  With the gain set at 1/4 of the way the house feels like it is going to explode. Too much amp? It also goes to red quickly on serious bass.

Asked by: Disease
The level will really depend on the amount of signal coming in. It sounds like you have a very strong LFE signal. It may help to lower the subwoofer level coming from the processor in this case.
Answered by: Chrisf
Date published: 2016-02-02

can the spa500 run 2 eminence lab 12'' pro subwoofer or is the yung sd500-6 better or do i need more power?

Asked by: cakes
More power is generally going to be better when driving subs. THe main thing you would want to consider when driving two is the impedance load, If you are using the 6 ohm version of the LAB sub then you can only get a 12 ohm or 3 ohm load. 3 ohms would be too low for this amp to drive safely.
Answered by: Chrisf
Date published: 2016-01-27
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