A plate amplifier is a compact lightweight amp. It comprises of a metal sheet with all the connectors and controls attached to it. It is screwed to the back of a stereo speaker or subwoofer, functioning as the device’s built-in amp. In this article, we are going to talk about some of the best subwoofer plate amplifiers currently available for sale. We analyzed their features and functions, and made a list of the amps with the highest quality and performance.
What is a Plate Amplifier ? – [ Video Explanation ]
Some more detailed explanation can be found at the end of the article.
Best Subwoofer Plate Amplifier – Comparison Table
Let’s get started.
Dayton Audio SPA250 Subwoofer Plate Amplifier
One of the best subwoofer plate amplifiers you can get your hands on is the Dayton Audio SPA250. It puts out 250 watts of clean unhindered power. It has a switchable low-pass filter, sub sonic filter, phase switch, bass boost, variable gain and other useful functions. It is ideal for car subwoofers and home theatre systems. The SPA250 is a Class AB mono amp. It is energy-efficient and draws less than 1 watt at stand-by mode. It has a switchable bass boost with a peak of 6 dB @ 35 Hz. It has RCA line-level (low-level) and banana jack speaker-level (high-level) inputs and outputs for connecting with various factory and after-market source units and speakers. The amp has automatic power on. It has an adjustable low-pass filter @ 24 dB/octave 40 Hz to 180 Hz. It has a 0ᵒ to 180ᵒ phase switch and variable gain. The device has speaker-level high pass outputs 6 dB/octave @ 90 Hz at 8 ohms and 180 Hz at 4 ohms. It also has full bandwidth line-level outputs 10 Hz to 20 kHz for daisy chaining additional amplifiers. There is a 12 db/octave sub sonic filter centered at 20 Hz for keeping out ultra-low frequencies. Damping factor of the amp at rated power is 114 @ 100 Hz. The Dayton Audio SPA250 can produce 156 watts RMS power into an 8 ohm load @ 0.1% total harmonic distortion (THD) and 252 watts RMS power into a 4 ohm load @ < 1.0% THD. Input impedance is 10.4K ohms and signal-to-noise ratio is 90 dB A-weighted. The gadget has manual, auto and triggered on/off modes for adapting with different audio systems. Dimensions of the SPA250 subwoofer plate amplifier are: width = 9-13/16 inches, height = 9-13/16 inches and depth = 5 inches. Cut-out dimensions are: width = 8 ½ inches x 8 ½ inches.
Key Features :
- Class AB mono subwoofer plate amplifier.
- RCA line-level and banana jack speaker-level inputs.
- Switchable bass boost, low-pass filter, sub sonic filter, phase switch, variable gain.
- Speaker-level high-pass outputs, line-level outputs.
- Power rating:
- 156 watts RMS @ 8 ohms at 0.1% THD.
- 252 watts RMS @ 4 ohms at < 1.0% THD.
Dayton Audio SA70 Subwoofer Plate Amplifier
Our next top-rated subwoofer plate amplifier is again by Dayton Audio. It is the SA70 plate amp with a power capacity of 70 watts. It has low-level and high-level inputs, a low-pass crossover, bass boost and other useful features. It is best suited for compact subwoofers like a car subwoofer. The SA70 is a powerful amp with a Class AB circuitry. It has a sealed rear cabinet which makes it ideal for upgraded computer subwoofers and individual tactile transducers. It has low-level (line-level) inputs for accepting signals from a preamp level source. The inputs take in stereo signals and convert them into mono signals. The amp has high-level (speaker-level) inputs which let you connect the speaker-level output of a full-range amp to the input of the subwoofer amp using a speaker wire. The gadget also has high-level pass-through with spring clip type jacks. The device is fully protected against thermal failure and short circuits. It has an auto turn-on functionality which conserves power when the system is not in use. It has a variable frequency 2nd order low-pass filter (60 Hz to 180 Hz) for screening frequencies entering the main speakers. The SA70 subwoofer plate amplifier has a measured power output of 45 watts RMS @ 8 ohms @ 0.1% THD and 70 watts RMS @ 4 ohms @ 0.2% THD. Signal-to-noise ratio of the device is 90 dB A-weighted and frequency response is 40 Hz to 180 Hz. Input impedance is 10.4K ohms. It has a TDA7294 IC-based Class AB topology for greater efficiency and power. It has variable gain control. It has a rear-mounted output lead for connecting it to the subwoofer driver. Dimensions of the amp are: 7 ½ inches width x 8 11/16 inches height x 3 ½ inches depth. It weighs 5.8 lbs. Its cut-out dimensions are: 6 5/8 inches width x 7 ¾ inches height.
Key Features :
- Class AB subwoofer plate amplifier.
- High-level and low-level inputs, high-level outputs, variable frequency 2nd order low-pass filter.
- Variable gain, auto turn-on, frequency response 40 Hz to 180 Hz.
- Power rating:
- RMS 45 watts @ 8 ohms @ 0.1% THD.
- RMS 70 watts @ 4 ohms @ 0.2% THD.
Yung SD300 Class D Subwoofer Plate Amplifier
The Yung SD300 is a great choice for a plate amplifier. It has a Class D circuitry with switching power supply for greater efficiency. It is ideal for home theatre subwoofers and car subwoofers. The Yung SD300 is fortified against extreme high temperatures, current overload and short circuits. It is capable of putting out high amounts of power for sustained periods without heating up or shutting down due to thermal failure. It has a built-in limiter circuitry protection that prevents peak overloads. The gadget has low-level, high-level and LFE inputs for connecting with different aftermarket and factory-installed source units and speakers. The multiple inputs offer a lot of flexibility in terms of connectivity. The amp has both manual and automatic turn on/off functions to adapt to different systems. It has a low-pass adjustment of 40 Hz to 200 Hz and a 0 to -180 degree phase switch. It generates 300 watts of continuous RMS power. It has a 6 dB bass boost centered at 30 Hz which makes it an ideal amplifier for sealed box subs and even some vented box variants. It has variable gain and switchable 115/230 V input voltage. The Yung SD300 is extremely compact and lightweight. It lets you optimize your space and experiment with different mounting options. It doesn’t heat up too fast and maintains an even temperature. Power rating of the amp is: 300 watts RMS into a 4 ohm load @ < 1.0% THD. Signal-to-noise ratio is > 90 dB at rated power. Dimensions of the amp are: width = 10 inches, height = 7 3/8 inches, depth = 2 ½ inches. Cut-out dimensions are: width = 9 ¼ inches and height = 6 5/8 inches.
Key Features :
- Class D subwoofer plate amplifier with switching power supply.
- Low-level and high-level inputs, bass boost, variable gain, low-pass filter, phase switch.
- Manual and automatic turn on/off, built-in limiter circuitry protection.
- Power rating 300 watts RMS @ 4 ohms @ < 1.0% THD.
Dayton Audio SPA1000 Subwoofer Plate Amplifier
Dayton Audio is a world-renowned audio equipment maker. It makes top-quality products that stand the test of time. The SPA1000 subwoofer plate amplifier is one such gadget. It is a state-of-the-art monoblock amplifier that combines the best of Class G, Class D and Class AB amps. It has a Class G circuit topology and the high-fidelity operation of a Class AB amp with a patented tracking down converter power supply to boost efficiency to 86%. The result is unbeatable Class D-like efficiency without any reliability or sound quality issues. The Class AB output stage makes sure you get distortion-free sound minus the problem of instability that most high-efficiency amps have to deal with. The tracking feature of the amp pumps out just the right amount of power needed for your subwoofer based on demand. Unlike other amps, it does not keep it in reverse. The output stage only pulls in the power it requires at any given point in time. The benefit of this type of circuitry is that less power is wasted as heat and more power is available for the subwoofer driver. The smart thermal management of the SPA1000 gives it a clear edge over its peers, and makes it a favorite among audiophiles. The gadget has a Toroidal power supply transformer. It has a low-frequency parametric EQ for personalizing the output. The advanced soft clip circuitry safeguards your subwoofer and offers more headroom. The amp has an Optimized Thermal Circuit which protects it against thermal damage during sustained playing periods. The Hercules heat-sink further helps in dissipating heat and keeping inside temperatures low. Power output of the amp is: 497 watts x 1 @ 8 ohms and 950 watts x 1 @4 ohms. It has a 30 Hz to 200 Hz low-pass filter, adjustable phase and RCA input connectors. Dimensions of the amp are: height 11 15/16 inches, width 11 15/16 inches, depth 5 ¼ inches.
Key Features :
- Class AB mono-channel subwoofer plate amplifier.
- Patented tracking down converter power supply, Toroidal power supply transformer.
- Low-frequency parametric EQ, Optimized Thermal Circuit, Hercules heat-sink.
- Low-pass filter, adjustable phase and RCA input connectors.
- Power rating: 497 watts x @ 8 ohms, 950 watts @4 ohms.
Yung SD100-6 Class D Subwoofer Plate Amplifier
The Yung SD100-6 is a top-selling subwoofer plate amplifier for custom designs and replacement duties. It is a 100-watt Class D single-channel amp with a compact frame. It has a switching power supply for greater efficiency. It has a durable heat-sink that keeps temperatures moderate during continuous max-power operation. It prevents shutdowns due to overheating and keeps the system going for hours. It has an internal peak limiting circuit that prevents overload. It is also protected against sudden fluctuations in voltage and internal and external faults. The Yung SD100-6 has low-level and LFE inputs. It has a bass boost of up to 6 dB centered at 45 Hz which ideal for sealed box installations and some vented box designs. It has a variable low-pass filter (40 Hz to 200 Hz) Hz toHz and phase control (0 to -180 degrees). It has auto turn on/off and LED power indicators. The amp has low-level inputs and outputs. It has an IEC power socket. Low-level input sensitivity is 210 mV/ 50 Hz. Power output of the device is 100 watts RMS x 1 @ 4 ohms. It has a signal-to-noise ratio of > 90 dB at rated power and total harmonic distortion of < 1%. Dimensions of the subwoofer plate amplifier are: 8 inches width x 7 inches height x 2 ¼ inches depth. Cut-out dimensions are: 7 ¼ inches width x 6 ¼ inches height.
Key Features :
- Class D 100-watt subwoofer plate amplifier.
- Switching power supply, internal peak limiting circuit, low-level and LFE inputs.
- Bass boost, variable low-pass crossover, phase control, auto turn on /off.
- Power rating: 100 watts RMS x 1 @ 4 ohms.
Yung SD500 Class D Subwoofer Plate Amplifier
The Yung SD500 is another high-performance subwoofer plate amplifier. It is a 500-watt Class D amp with an advanced switching power supply system for more efficient power delivery. It is designed for high-power applications that require a continuous supply of power. The amplifier puts out an RMS power of 500 watts @ 4 ohms. It can function for sustained periods at max capacity without thermal failure. It features a limiter circuit protection that safeguards against overloads and over-currents. It has manual and automatic turn on/off functions for more flexibility. The Yung SD500 has low-level (RCA-level), high-level (speaker-level) and LFE inputs for connecting with various factory and after-market devices. It has phase control, variable gain and adjustable crossovers for optimizing the subwoofer output. Low-pass filter range is 40 Hz to 200 Hz and phase adjustment is from 0ᵒ to 180ᵒ (reverse). The device has switchable 115/ 230 V input voltage. It is compact and lightweight and makes for flexible mounting. Input signal is received through a pair of RCA-type jacks, including the means to accept the output of an A/V receiver’s LFE output. Dual RCA jacks are also available for line-level loop-through. Apart from this, the amplifier accepts high-level input signals through binding post terminals. Power rating of the amp is: 500 watts RMS x 1 @ 4 ohms @ < 1.0% THD. It has a signal-to-noise ratio of > 90 dB. Low-level input sensitivity is 210 mV/ 50 Hz and high-level input sensitivity is 3.0V/ 50 Hz. The amp measures 9-7/8 inches (W) x 10-5/8 inches (H) x 3 inches (D). Its cut-out measurements are: 8-7/8 inches (W) x 9 ¾ inches (H).
Key Features :
- 500-watt subwoofer plate amplifier with Class D circuit topography.
- Low-level, high-level and LFE inputs, low-pass crossover, phase control.
- Switching power supply, limiter circuit protection, manual and automatic turn on/off.
- Power rating 500 watts RMS @ 4 ohms @ < 1.0% THD.
Dayton Audio SPA250DSP Subwoofer Plate Amplifier
The Dayton Audio SPA250DSP is a reliable plate amplifier. It features DSP functions like 7 PEQ bands, low-pass filter, high-pass filter, sub sonic filter, phase control, limiter, and mains delay. It has a Class D circuit for high-impact low-frequency performance. The SPA250DSP has balanced and unbalanced low-level inputs and outputs for versatile connections. It has a fast and intelligent PC-based GUI software that allows better access to the DSP functions. It has USB control for PPC-GUI communication with special PC software included in the amp. It has a single-knob control panel for ease of use. It also has a high-contrast easy-to-read LCD screen and LED indicators to show the status of the system. If the indicator is red, it means the system is in power-saving stand-by mode. If it is green, it means it is operating normally. The SPA250DSP plate amp has both low-pass and high-pass crossovers. The low-pass filter ensures high and midrange frequencies stay out of the subwoofer for a neat bass output. The high-pass filter ensures low-end frequencies do not enter the main speakers which can damage them due to excessive excursion. The amp has adjustable phase. It has an auto mode which puts it on stand-by if no input signal is received for more than 20 minutes. Power rating of the amp is 250 watts RMS @ 4 ohms @ <0.1% THD+N. Signal-to-noise ratio is 97.9 dB A-weighted. The gadget is 10.25 inches high, 7.25 inches wide and 2.125 inches deep. Its cut-out height is 9.25 inches and width is 6.25 inches.
Key Features :
- Class D plate amp with DSP functions.
- Balanced and unbalanced low-level inputs and outputs.
- High-pass filter, low-pass filter, sub sonic filter, phase control, limiter, mains delay.
- PC-based GUI software, single-knob control panel, LCD screen, LED status indicators.
- Power rating: 250 watts RMS into a 4 ohm load @ <0.1% THD+N.
Factory Buyouts B-52 ACTPRO-18F HD Professional Subwoofer Plate Amp
The final plate amp on our list is the B-52 ACTPRO-18F HD by Factory Buyouts. It is a sophisticated subwoofer plate amplifier with Class G circuit topography. It pumps out 1000 watts of pure clean power for high-output bass reproduction. The amp has an integrated BBE Sonic Maximizer that adds low-end punch and top-end clarity to the sound. It has HF process and LF contour control. It has an onboard compressor/ limiter and a sub sonic filter (32 Hz, 12 dB/ octave) to remove distortion. The B-52 ACTPRO-18F HD is fully protected against thermal shutdowns and short circuits. It can function at it maximum power level for hours on end without thermal set-backs. The device has a low-pass filter (100 Hz, 18 dB/ octave Butterworth) and a satellite high-pass filter (100 Hz, 18 dB/ octave Butterworth). It has a 0 to 180 degree (reverse) phase switch and a ground lift switch. It has balanced XLR input, balanced XLR full-range output, and left and right balanced XLR high-pass outputs. The subwoofer plate amplifier has a large heat-sink with convection cooling. It has a large Toroidal transformer. It has LED indicators for power, protect, limit and signal. Power handling of the amp is 1000 watts. Frequency response is 30 Hz to 150 Hz and impedance is 4 ohms. The device is 10.25 inches wide, 19.75 inches high and 4 inches deep. Its cut-out measurements are 18 inches by 8.625 inches.
Key Features :
- Subwoofer plate amplifier with Class G circuitry.
- Power rating 1000 watts @ 4 ohms, BBE Sonic Maximizer, HF process and LF contour control.
- Thermal and short protection, low-pass and high-pass filter, phase switch, ground lift switch.
- Oversized heat-sink with convection cooling, Toroidal transformer, 30 Hz to 150 Hz frequency response.
What is a plate amplifier?
A plate amplifier is a shallow-frame amplifier that is mounted to the rear panel of a speaker or subwoofer. It is a power amplifier built on a flat board or metal sheet for installation behind a speaker. Its works like a regular amplifier i.e. it takes in a line-level signal (weak signal) and boosts it to drive a loudspeaker. The only difference is that it has limited frequency response which makes it ideal for powering subwoofers.
A plate amplifier is designed to be mounted inside the enclosure of a subwoofer, be it vented or sealed. Most ready-made subwoofers come with built-in amps. But if you wish to build a subwoofer from scratch, you might need one of these. The best way to mount a plate amp to a sub is to cut a hole in the rear wall of the sub and screw the amp to it.
A plate amp has a face plate that contains all the inputs, outputs, controls and power connections. The other side of the plate has the exposed elements of these components. When you attach the amp to the back panel of a sub, the control panel faces outward while the exposed side stays inside.
In other words, you have all the inputs and outputs on the outside and all the wiring on the inside, tucked away safely and hidden from view. The only connections on the inner side of the board are a pair of speaker terminals which link the amp’s main output to the subwoofer driver.
A plate amp is mostly square or rectangular in shape with a shallow depth so that it doesn’t take up too much space inside a subwoofer enclosure. The plate is commonly made of steel or aluminum. A plate amp can be used to build powered speakers and subwoofers, although it is more suitable for subwoofers due to its narrow frequency response.
The main difference between a regular amplifier and a plate amplifier is that a regular amp has a chassis covering on all sides, but a plate amp does not. A regular amp has a housing that contains the amplifier circuitry and all the components that make up the amp.
A plate amp, on the other hand, is just a metal sheet with the amp circuit board and other parts secured to it. It lacks a chassis or enclosure around it. It is just a flat piece of metal with all the inputs, outputs and controls built upon it.
A plate amp is cheaper than a regular amp because it does not have the additional cost of an enclosure. It also occupies less space inside a speaker box. Because a plate amp lacks a chassis, the sub box becomes the amp’s chassis once the amp is fully installed. Also, as mentioned already, a typical amplifier has a wider frequency response than a plate amp. Therefore, it is capable of driving a wide range of speakers whereas a plate amp is more restricted to subwoofers. In fact, most store-bought powered subwoofers today use plate amps because of their compact size and mounting flexibility.
Read our article on how does an amplifier work ?
Read our article on how does an amplifier work ?