Pioneer GM-A4704 4-Channel Bridgeable Amplifier Review

Pioneer GM-A4704 4-Channel Bridgeable Amplifier Review

Inexpensive in price, the Pioneer GM-A4704 caught our eye and we couldn’t help but make a write-up about it. Numerous features could serve those well, including:

  • 520 watts of max power
  • Automatic signal sensing and automatic turn-on
  • A variable high-pass filter
  • Speaker level inputs for maximum convenience
  • Compact design with large sound
  • No distortion in your sound quality

The Breakdown of the Features

Within this 4-channel bridgeable amplifier, you’ll be able to reap the benefits of a maximum power output of 80 watts at 4 ohms, with a total harmonic distortion of <0.05% (10W, 1HZ). Beyond this, the fuse rating is 30A, and you’ll be able to jump in and use this Class AB amplifier with ease. The maximum power output is 130W at 2 ohms, with a frequency response range of 10Hz – 70kHz. This bridgeable unit provides more than enough power for the intended purpose, and is quite inexpensive for the quality offered.

You also don’t have to worry about an incredible amount of distortion, as this works well automatically and reduces any distinct and unnecessary noises. Looking for punchy bass that will blow you away? Look no further, as the Pioneer will work splendidly. Maybe you have two OEM amps that you’re looking to spice up? If so, the Pioneer GM-A4704 would be a great addition to do that with! Beyond this, it also works great with an RCA setup that’s 4-channels, for optimal convenience!

You may also drive multiple subwoofers and speakers, while being bridgeable in order to power a single sub, as well. While the design may not be that robust, it allows you to have that large sound that you’ve always dreamed of – in a compact and non-bulky manner! There’s one-body heat sink, and even gain adjustment that allows you to go up to 6.5V – you can make your car sound as if you’re really at a concert!

The speaker terminals are the screw-type, and you won’t have to worry about this breaking easily. Screwed down and ready to be installed in your sound system, you can take your car and your audio on the drive of a lifetime. Before we discuss out our first impression of the GM-A4704, it’s worth noting that the high voltage input is 300 mV – 6.5V.

The First impression of the Product

When you purchase this bridgeable amplifier, you automatically receive the unit, an installed 30A ATO fuse, an input harness with eight 4-inch wires that’s speaker-level, owner manuals in English, Spanish, and French, as well as a warranty sheet to note what counts under warranty and what doesn’t. There’s also a 60-day money-back guarantee for those who purchased on a whim or had issues with the product before the two-month mark was hit. With all of this being said, we think it’s a great product that does present numerous features in which you can benefit from.

If you want to improve the sound quality of any vehicle you own, you may want to turn to the GM-A4704. Once installed, you’ll find that the quality of sound is enticing, and may urge you to dry more. Who knows – maybe you’ll end up taking the long way home for once! Not only does it power your front speakers, but it’s also capable of powering your back speakers and putting you in the midst of the music – or podcast (whatever you listen to, this bridgeable amplifier does it well!) Maybe you’re somewhat of a connoisseur when it comes to music and sound quality; if so, you’ll be able to hear more details in your audio with this installed than not.

Overall, this punchy little Pioneer was incredibly easy to install, even for a car noob. The clarity and sound within this unit on even the lowest settings sounds great, and you can even use it in older vehicles. It’s been said that Jeeps as old as 16-years can handle this with ease, and you don’t have to run out and buy another if you don’t have a modern vehicle. The stock sound of your car may sound pretty good, but it’ll sound even better when you give it that “umph” it was meant to be heard with.

The Advantages of the Product

  • Doesn’t require a remote control for usage
  • Automatically selects the proper signal for the input mode, whether speaker level or RCA
  • When the receiver is on, the Pioneer automatically turns on, as well
  • Protection control system equipped
  • Great price for the amount of performance received

The Disadvantages of the Product

  • Doesn’t come with a remote control for convenience
  • If you don’t have A/C, this unit may run a bit hot
  • May become warmer if you have the volume up higher

Is There Any Warranty?

Thankfully, there is a 1-year warranty, unless you don’t purchase from a verified retailer. When you purchase cheaper from a third-party seller, you run the risk of not being able to get your money’s worth it there are any issues found upon using. There’s also a 60-day money back guarantee for those that want to make sure they’re able to return if necessary.

The Final Verdict

This piece is fantastic and inexpensive, allowing you to get the punchy bass you’ve always wanted. While there are other products out there that may deliver you even better sound, you’ll most likely be spending a lot more. The Pioneer GM-A4704 is a great, low-budget option for those that want high-quality sound for a low price. Furthermore, the Pioneer GM-A4704 is great for those that are scared of taking the plunge, but want a security net just in case. With a 60-day money back guarantee, as well as a 1-year warranty, you’ll be able to try this out and find if it works for your car or your listening style.


Troy is a freelance sound engineer with over ten years’ experience in the music industry. His passion for music started when he was young. He would often be found dismantling old radios or television sets and fixing them. Troy is renowned for hosting some of the best live concerts in his hometown. When not working, Troy loves taking his thirsty Ford Mustang for a long drive in the wild. He has been married to Jane for the last 20 years, and together they have two lovely girls. His also known for his delicious, honey coated, barbecued pork chops; which he prepares in his backyard.