subwoofer plate amplifier with jack connected

Subwoofer Plate Amplifier: The Ultimate Guide

Whether you are planning a movie night with friends or setting up a karaoke bar for the weekend, you’ll need good bass and this is where a subwoofer plate amplifier comes in. To help you zero in on one easily, we’ve laid out a comprehensive guide all about sub amps and then reviewed the top 5 available.

What is a Subwoofer Plate Amplifier?

A subwoofer plate amplifier is a specialized speaker that takes line-level signals, increases their power at a limited frequency to reproduce bass and improves clarity of the stereo which creates a theater-like experience.

Generally, subwoofer plate amplifiers are engineered with a wide range of wattages where the lowest is 100 and the highest is 1100. Which capacity works for you depends upon the type of situation the sub amp is needed in.

Speaking of situations, a subwoofer plate amplifier has a lot of applications. It may be used in:

  • Cars
  • High-fi home entertainment systems
  • Theaters

Is a Subwoofer the Same as an Amplifier?

No, a subwoofer is not the same as an amplifier but they complement each other to create harmony in sound. Put simply, a subwoofer creates sound waves also known as the load which is measured in ohms whereas an amplifier increases the level of sound based on the load it recognizes which is measured in watts.

To match a subwoofer’s impedance to an amplifier’s power, it is important to know what type of audio system is set up. When the amp complements the sub, the bass is leveled up creating an immersive experience. Without the match, the sounds won’t correspond.

Can I Connect a Subwoofer to a Normal Amplifier?

Technically, yes a subwoofer can be connected to a normal amplifier but before the cables are matched, it is important to know whether the sub is powered or non-powered. Powered or active subwoofers have amps built-in so an external added connection may not amplify the bass as required whereas a passive subwoofer does need an external amp connection to create clarity in the stereo’s sound.

However, as an audio system is generally built on a variety of speakers, receivers, amps, and subs, one can use an external amp connection on a powered sub to pass information between the sound system and the passive speakers.

In this case, it is crucial to the safety of the amplifier and the powered subwoofer that the wattage capacity of the amp matches with the impedance or ohm specification of the sub. Remember, the external amplifier won’t amplify the bass, it’ll only power the built-in amp.

A subwoofer can also be connected to an old amplifier but it does require a technical know-how. Also, one amp can power two subwoofers after attempting a series of steps which will result in a serious amount of bass. If there is power in the amplifier but there is no sound to sub, there are ways to troubleshoot and get back the bass.

How Does a Subwoofer Amplifier Work?

The overall functioning of a subwoofer amplifier is actually simple. The connected or built-in amp on the subwoofer filters out the high frequency signals and amplifies the audio of low frequency signals, also known as the bass, which is then improved by the subwoofer by minimizing noise.

If you’re making a sub amp from home, here’s what you’ll need:

  • Amplifiers to filter the low frequency signals
  • Voltage amplifier to amplify the low frequency signals
  • Transistor to convert the amplifier’s output into power signals
  • A load resistor to balance the power signals
  • Batteries to power the system
  • Power supply voltage to keep the system running
  • Capacitors to store electricity for the amplifier

As a general rule of thumb, the frequency of the subwoofer amplifier should be kept no less than 20 Hz and no more than 200 Hz.

Do I Need a Subwoofer Amplifier?

If you want a sound system that has minimal noise, a good bass, and produces high quality audio then yes, a sub amp is essential. Today, it is widely used in a number of places such as:

  • Dance clubs or DJ sets to amplify the bass
  • Home theater systems to create an immersive atmosphere
  • Public conferences to reach a large audience
  • Cars for long distance travel
  • Churches for better sound
  • Cinemas for the surprise element

Sub amps have been integrated as a norm and can be used anywhere. As it minimizes noise, the loud bass does not irritate the audience.

5 Best Subwoofer Amplifiers Reviewed

1. Dayton Audio SPA250 250W Subwoofer Plate Amplifier

Dayton Audio SPA250 250W Subwoofer Plate AmplifierDefined as an all-rounder by sound experts, the Dayton Audio SPA250 comes with multiple modes of function and it can be powered manually, automatically, or triggered on/off making it exceptionally suitable for home theater systems.

The ease of usage is enhanced by its performance. The sub amp’s 35 Hz bass boost delivers crystal clear audio and improves the overall punch. 

Also, the sub amp is highly flexible and can work with a multitude of automated systems, even powered subs with failed amps! This is due to the variable gain and switchable phase controls that flawlessly optimize room integration.

Speaking of the room, the Dayton SPA250 is designed in an all-black front with red buttons which blend into the background seamlessly.

It also comes with a high-level and low-level input which connects the Dayton SPA250 to any system and allows even beginners that are new to the speaker building world to create a flawless system.

The system covers all its bases by providing labels to every function and making matters easy on the user. 


  • Variable Gain
  • 35 Hz Bass Boost
  • Low-level and High-level Input
  • Multiple modes of function
  • Switchable Phase Controls


  • Seamless design
  • Powerful amplifier
  • Crystal clear sound


  • The power cable may seem sloppy


2. Dayton Audio SA100 100W Subwoofer Plate Amplifier

Dayton Audio SA100 100W Subwoofer Plate AmplifierConsidered one of the most reliable sub amps on the market, the Dayton SA100 is a small-sized sub amp offering a wide range of features that make the installation easy on the user.

It comes with the traditional banana plug connectors on the left and right side that provide high and low level input/output.

The low pass crossover is adjustable and the system comes with an automatic on/off button thàt, unlike most amplifiers, comes on when the volume is just 30%.

Also, the Dayton SA100 works with a variety of receivers which allows sound system hobbyists to set it up at home easily and without worry. 

Speaking of setting up, the system comes in a small size which allows it to work as a replacement for many sub amps and does not pose a risk to the sound system.

The sound quality of the sub amp is also unmatched, the bass is punchy, and no matter how high the volume is, the quality isn’t compromised.


  • Low distortion audiophile sound
  • Adjustable low pass crossover
  • Phase reversal switch
  • 75W RMS @ 8 OHMS, 100W RMS @ 4 OHMS
  • High-level and low-level input and output
  • Automatic on/off


  • Small size
  • Ideal for long-term usage
  • High-quality sound


  • May need a few modifications when used as a replacement


3. Dayton Audio SA70 70W Subwoofer Plate Amplifier

Dayton Audio SA70 70W Subwoofer Plate AmplifierThe Dayton SA70 is affordable but packs a punch in a compact design. 

In its small structure, it includes low and speaker level inputs which allow it to be compatible with many, if not every, system. This is especially helpful for users looking to replace their sub amp without breaking the bank.

For those that are building their own sound systems, the Dayton SA70 comes with a variable 2nd order low pass crossover from 40Hz to 180Hz, providing decent power to the overall system.

A notable feature of the high-quality SA70 is its auto-on button which removes the need for manual labor and adds the perfect amount of bass to a sound system, at the right time.

Also, the small structure allows it to be best as a replacement sub amp and makes handling easy on the user. Though the sound quality could be better, the Dayton SA70 is still considered as one of the best systems available under $100.


  • Line-level and speaker-level inputs for system compatibility
  • Auto-on circuit
  • Variable 2nd order low-pass crossover from 40Hz to 180Hz
  • Compact Design


  • Affordable but beefy circuit
  • Small size
  • Compatible with any system
  • Auto-on feature


  • The sound quality could be better


4. Dayton Audio SA25 25W Subwoofer Plate Amplifier

Dayton Audio SA25 25W Subwoofer Plate AmplifierFor less than $60, the Dayton SA25 provides a multitude of features that are better than any audio system available in this range.

It comes with line-level and speaker-level inputs which enhance the compatibility of the sub amp and allow users to connect it to any sound system without risking the functioning of the receivers or the speakers.

Speaking of speakers, the SA25 also features a speaker relay which prevents turn-off thumps and improves the sound quality.

The 25W RMS is true to its claim and is able to reach 100dB with many drivers easily. Also, the variable 2nd order low-pass crossover makes matters easy by minimizing noise and adding an extra oomph to the bass.

Best of all, since it measures only 6-5/16″ square, the ultra-compact size allows the Dayton SA25 to fit in the smallest enclosures and work efficiently. This also means it blends into the background seamlessly and does not feel obtrusive to the audience.


  • Line and Speaker-level inputs
  • Speaker relay
  • Variable 2nd order low-pass crossover from 60Hz to 180Hz
  • 25W RMS 


  • Ultra-compact structure
  • Affordable
  • 25W true-to-claim power


  • The audio quality could be better



Dayton Audio SA25 25W Subwoofer Plate Amplifier

Dayton Audio SA25 25W Subwoofer Plate AmplifierThe Bash 500W sub amp is one of the most powerful additions to any sound system. It is designed with characteristics that rival the best audio systems and leaves little to no room for improvement.

Its compact and lightweight design makes it easy to transport and

 does not add bulk to the storage. Also, it allows users to handle it carefully without damaging the other parts of the sound system.

The 500W power output is true to its claim and produces crystal clear audio powered at 0.5% THD into 4 ohm load. Speaking of audio, the limiting circuit prevents audible clipping, minimizing noise and improving the sound quality.

When setting up the system, the line and speaker level inputs come in handy and allow the sub amp to connect to any speaker seamlessly. The manual labor ends here as the auto on/off feature handles the rest by turning the sub amp on at the right time and off when the system is shut down.


  • Compact, lightweight design
  • High 500W power output
  • Line and speaker level inputs
  • Limiting circuit
  • Auto on/off


  • Lightweight design
  • Compatible with any system
  • Prevents audible clipping


  • Overheats fast


Frequently Asked Questions:

Can you amplify a powered subwoofer?

There is no need for an amplifier to be connected to a powered or active subwoofer as the amp is already built-in. However, when working with a passive set of speakers, you could connect the amplifier with the powered subwoofer using two RCA cables and a power source for data transmission.

What is the difference between a passive and active subwoofer?

An active subwoofer, also known as a powered sub, has an amplifier built-in while a passive subwoofer is one that needs an external connection to an amplifier to function. In the case of passive subs, it is important to match the amp’s power specs to the sub’s impedance specifications.

Final Thoughts

Now that you’ve stepped into the world of subwoofer plate amplifiers, you are just one step away from experiencing music, movies, and audio systems unlike any other right in the comfort of your home. Pick one from the five best sub amps above and create the best audio system for yourself.