Garrett ACE 400 Review

by Chad Eicher

Garrett ACE 400 review

This is the definitive Garrett ACE 400 review.

These days, the metal detecting market is filled with options to cover all price ranges.

Unfortunately, finding the balance between affordability and capability is easier said than done.

The Garrett ACE 400 helps to fill that much-needed market gap. It’s a feature-rich detector that’s affordable and simple enough for beginners to use.

The Best Metal Detector?

We’re on a mission to find the best metal detector.

Although the ACE 400 didn’t make the top of our list, is still a solid choice, especially for a beginner…

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With this review, our goal is to highlight everything this detector has to offer so that you can make a purchasing decision you won’t regret.

Whether you’re new to the world of metal detecting or not, there’s a good chance you’ve heard of Garrett.

This US-based brand has been around since 1964 and continues to be a leading innovator in the industry.

The company is highly respected in the field, thanks to its impressive build quality and quality control. Every device, including the ACE 400, is manufactured in Texas. Not only that, but Garrett is an ISO 9001-certified company, which ensures top-notch quality all around.

Garrett ACE 400

The ACE 400 is part of Garrett’s most popular line of products (we have compared the best Garrett metal detectors in this article). While the brand does offer heavy-duty detectors for professional applications and serious hobbyists, the ACE line focuses on affordability and accessibility.

It caters to those who want a reliable metal detector without breaking the bank. The 400 happens to be the premium option in the ACE line, giving you a lot more features to work with.

Here are some of the most notable features of the ACE 400.

Garrett ACE 400 Design and Build

When you take a look at the ACE 400, you’ll notice that there’s a noticeable difference in build quality compared to some cheaper models out there. This detector is solid and well-made. The profile is simple, consisting of a base pole, a small control box, and a sizable coil.

However, Garrett has engineered the detector to be comfortable and easy to balance in your hand. On one end, you have an arm cuff that’s made out of molded plastic. An adjustable strap on top allows you to make finer adjustments to get the perfect fit.

The cuff sits on the bottom of your arm. Thanks to the weight of the search coil, the cuff applies some light pressure to create a lever effect. There’s also thick padding to create a comfortable grip for better leverage. Overall the detector is very lightweight, tipping the scales at just under 3 pounds.

1. Waterproof DD Coil

You’re not getting a standard circular search coil with the ACE 400. Instead, it’s equipped with a DD search coil that measures about 8.5 inches wide and 11 inches long. Dubbed the “PROformance Coil,” this unique component enhanced performance tenfold.

When compared to a traditional coil, DD coils tend to offer far better performance. It’s more stable and has better sensitivity to small items or metals with a lower conductivity level. That’s because the distinct shape creates a different electromagnetic field pattern when you’re searching. Instead of the conical search pattern you get with traditional units, you’re getting a wider search path that’s heavily concentrated. Thus, it’s able to penetrate deeper into the soil.

Did we mention that it’s waterproof, too? You can search several inches below the surface of the water to find even more treasures. Keep in mind that the unit itself is not protected from water. You can’t dunk the entire device in the water.

2. User-Friendly Controls

ACE 400 control-panel

One of the things we like most about the Garrett ACE 400 is the control box. It offers tons of flexibility to give you the performance you’re after. However, it’s not complicated to use. The large LCD screen provides all the information you need, and the simple push buttons let you make adjustments on the fly. There are no complicated knobs or analog meters to worry about. As a result, the machine is easy to get the hang of regardless of your skill level.

3. Weather-Ready Extras

This particular model comes with a few handy extras that can make all the difference as you prospect. With the detector, you’re getting a search coil cover and a control box cover. The latter accessory slips onto your control box to protect it from light drizzles. The clear plastic window ensures that you can still take advantage of all the functionality the device has to offer. On top of those two protective extras, the machine also comes with a carrying case and Garrett’s EasySound headphones.

Garrett ACE 400 Best Features

The Garrett ACE 400 is a feature-rich detector. There’s a lot to discover about this model. Here are some of the most noteworthy features that might affect the way you search for metals.

1. Innovative Iron Audio System

The Iron Audio system is a cool little feature that will make it easy to distinguish between valuable metals and junk metals before you start digging. Within the control box are some complicated mechanics that can separate metals based on conductivity levels.

The detector uses that information and works alongside the built-in discrimination system to identify iron in an instant. You’ll hear subtle nuances in the audio alert tone, which may make it easy to ignore items you don’t want. Think of it as feeling the object with sound.

2. Target Identification and Analysis

The Garrett ACE 400 doesn’t just provide audible feedback about the metal composition of an item. You can also see what an item is directly on the screen.

Using several identification methods, this machine is capable of telling you where the item falls within the conductivity spectrum. The Digital Target ID system provides that information as a number between 0 and 99.

There’s a graphical analysis system as well. This feature can let you know the size, shape, and material through simple symbols on the control box.

3. Depth Indicator

As if the system’s impressive identification features weren’t enough, the Garrett ACE 400 can also give you some basic depth information. This feature isn’t as complex as those found on premium detectors, but it certainly gets the job done.

The LCD screen has a simple bar chart to let you know if the item is 2, 4, 6, or 8 inches below the surface of the soil.

Garrett ACE 400 Detection Features

ace 400 features (comparison with ace 300 and ace200
Ace 400 compared to Ace 300 and Ace 200

Despite its affordable price tag, the ACE 400 does very well across the board in terms of performance. It has some unique features that are typically reserved for more expensive models.

1. Adjustable Operating Frequency

This device is a VLF or Very-Low Frequency detector. Without getting too much into the technical weeds, VLF technology pumps out a constant electromagnetic wave that interacts with metal objects in the soil.

The cool thing about the ACE 400 is that the frequency of the electromagnetic wave is fully adjustable! You can fine-tune the settings to have full control over the performance. It’s adjustable up to 10 kHz.

2. Iron Discrimination and Notch Discrimination

If you’re interested in searching for specific types of metals, the ACE 400 has you covered. It’s equipped with iron and notch discrimination. The iron discrimination feature works alongside the Iron Audio system to help you identify junk metals. You can choose to ignore those metals altogether so that you can focus on other items.

The same goes for notch discrimination. This is a filter that forces the detector to ignore certain frequencies. You can easily set new notches as you search, making the detector a highly efficient tool for finding specific lost items.

3. Multiple Sensitivity Levels

In total, the ACE 400 has 8 different sensitivity levels to choose from. With a push of a button, you can adjust those levels as you work. This might be useful if you’re trying to find smaller items or objects with low conductivity levels. Upping the sensitivity can help you uncover treasures that are buried deeper into the ground.

The ACE 400 was included in our list of the best metal detectors for coins. Go check it out if you want to know what model took the first place.

Garrett ACE 400 Pros and Cons

  • Easy to use design
  • Adjustable frequency up to 10 kHz
  • 8 sensitivity levels
  • 5 search modes
  • Digital Target ID and graphical display
  • Electronic pinpointing system
  • Iron discrimination with Iron Audio
  • Flexible Notch discrimination
  • Waterproof search coil
  • Comes with environmental cover, case, and headphones
  • Adjustable length and arm cuff
  • Can’t be fully submerged
  • No ground balance system

Garrett ACE 400 Frequently Asked Questions

1. Is the Garrett ACE 400 waterproof?

The Garrett ACE 400 has a waterproof search coil. However, it’s not fully waterproof. You can’t submerge the entire device. If you’re interested in learning more about waterproof metal detectors, check out the page here:

2. Can the Garrett ACE 400 detect gold?

While it’s not made for gold hunting, it is capable of finding gold jewelry in good conditions. Thanks to the higher operating frequency and sensitivity adjustments, it’s better at finding gold than many affordable options on the market.
If you are in search for a detector specificaly design for gold hunting I’d recommend reading our guide about gold detectors.

3. How deep can the Garrett ACE 400 detect?

Thanks to the adjustable sensitivity levels, the ACE 400 is capable of searching pretty deep into the soil. It can detect at least 8 inches deep with standard settings. However, you can go further with the right adjustments.

4. Is the Garrett ACE 400 good for saltwater?

Unfortunately, the ACE 400 is not made for saltwater use. It’s not protected from oxidation caused by saltwater. Plus, there is no ground balance feature to overcome mineralization issues.
Read this article with the list of the best metal detectors for saltwater and beachcombing.


Metal prospecting isn’t the most affordable hobby to get into. Top-of-the-line devices can set you back thousands of dollars. To make matters worse, a lot of cheaper options are devoid of important features that you need to find anything substantial in your search.

The Garrett ACE 400 addresses that market imbalance. It’s a relatively affordable detector that has some features that you usually don’t within this price range.

This includes adjustable frequency levels, notch discrimination, multiple sensitivity settings, and more. All of those settings are important if you’re serious about metal prospecting. Being able to get them without breaking the bank is a huge plus.

Furthermore, the ACE 400 is designed with simplicity in mind. It’s easy to use, making the hobby even more accessible to the masses.

All in all, the Garrett ACE 400 is a worthy investment. It strikes a good balance between affordability and performance. Want to see how the ACE 400 can change your prospecting game?

Garrett ACE 400 Alternatives

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Disclosure: Some of the links in this post are ‘affiliate links.’ This means if you click on the link and purchase the item, might receive an affiliate commission at no additional cost to you

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Article by

Chad Eicher

Detectorist Chad is passionate about metal detecting since he got his first metal detector as a gift when he was 12 years old. He created Metal Pursuits to share his knowledge and create the ultimate metal detecting resource on the web.


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