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Throughout my year’s detecting, the Garrett ACE 400 was one of the two most popular choices by beginner friends and family. So when sitting down to review the Garrett ACE 400 Metal Detector, I was already keenly aware of its capabilities firsthand.

This detector is designed with both beginner users in mind and it’s depth of features balance well with its relatively modest price.

Is the Garrett ACE 400 metal detector worth your money? It offers a variety of features and settings that make it perfect for beginner and experienced detectorists on a modest budget. So, what exactly makes this detector work well for beginners? Let’s take a closer look.

Initial thoughts on the Garrett ACE 400

The successor of the Garrett ACE 350, the ACE 400 refines the ACE series to its climax. It all boils down to iron audio, a large coil, and an additional 2 kHz putting the ACE 400 at a 10kHz adjustable frequency.

These additions up the performance and improves the device’s quality of life with iron audio for better target ID to reduce holes dug. Pushing what is one of the most popular entry-level models to the brink while still maintaining an affordable price of $421.12 on at the time of writing. I’ve even seen several specials pushing the 400 to $350, a mear $40 more than the Garrett ACE 300.

All things considered, the improvements aren’t a major step up from the ACE 300 but iron audio is another good feature for beginners. The added audible cue will help you better learn what signals to dig if you often find yourself in iron-rich areas.

Pros of the Garrett ACE 400 Metal Detector

  • Iron Audio
  • Simple Controls
  • Node Discrimination Controls
  • Built-in pinpointer
  • The ability to save a Custom discrimination mode
  • Lightweight
  • Largest stock coil of the Garrett ACE series
  • Storable headphones included with the detector

Cons of the Garrett ACE 400 Metal Detector

  • Fixed Ground Balance
  • The control box isn’t waterproof

Features of the Garrett ACE 400 Metal Detector

The ACE series rounds out with a well-rounded device that brings iron audio to its toolset. While it’s not the biggest upgrade over the already capable ACE 300, it adds the cherry on top for what I consider one of the top entry-level metal detectors on the market.

Iron Audio

As every detectorist quickly learns, you’ll be digging a lot of iron. In areas where iron and trash are common, the majority of the day will be spent digging, and properly fixing trash holes.

Any possible way to reduce the number of holes dug with increased confidence is a good one. With the added audible cues that help you quickly interpret the target as a likely iron object, you can move on to better-sounding opportunities without worrying that you left something good behind.

This isn’t a must-have feature but I think it brings good value to new detectorists that are still learning. With iron audio, Digital target ID, and node discrimination, you will be able to rely on your device and better learn what targets are worth digging by a combination of those signals.

Digital Target ID

The digital target ID feature on the Garrett ACE 400 Metal detector is one of its most valuable features. For beginners, the added feedback improves your ability to learn and recognize your detector’s audible cues.

To generate the ID, the metal detector sends out a signal that is reflected back by the targets in the ground. By analyzing the strength and frequency of the reflected signal, the detector is able to determine the type of metal that is present.

This information is then displayed on the LCD screen in large numbers, and on an ID cursor that’s on the top of the screen. This information combined with the other cues your detector provides allows you to make an informed decision about whether or not to dig.

In addition to its ability to identify different types of metals, the digital target ID feature also helps to eliminate false positives.

Iron check (better iron resolution)

If you’re just familiarizing yourself with metal detectors, you’ll want to consider the machine’s Iron Resolution. This is important because it tells you how well the metal detector can discriminate between targets and iron-based trash.

Both the ACE 400 and ACE 300 stand out in the series over the ACE 200 model because of their improved iron discrimination levels. Currently, both the 400 and 300 models have 4 iron discrimination channels while the 200 only has 1.

If you’re in an iron-rich area, whether it’s mineralization or trash, you have to have a higher level of iron discrimination.

Adjustable Notch Discrimination

Adjustable notch discrimination allows you to target certain types of metal. By controlling and customizing these settings, you can better isolate lost coins, jewelry, and other metal objects.

For example, you could use it to exclude aluminum cans from your search. Or, if you’re looking for gold, you could set it to discriminate against silver and lead. Adjustable notch discrimination is a great way to customize your metal detecting experience and find exactly what you’re looking for.

There are several pre-programmed search modes that will adjust your the detector’s node discrimination based on some general target types. As you learn to better control the targeting, there is even a custom search mode slot that lets you save your preferred controls.

Node discrimination helps to make the Garrett ACE 400 perform regardless of the setting. You can take it to a busy beach, use it on a farm field, or search the back woods and filter out the common junk for your area.

Unfortunately, all Garrett ACE series detectors lack adaptable ground balance abilities which would take location flexibility even further. That feature is typically reserved for more expensive devices though, and the ACE 400 finds itself better compared to the top options for modest budgets and beginners.

Coin Depth Indicator

The depth detector displays how deep a target is in increments of two inches with a maximum depth of eight inches. While a depth indicator isn’t a necessity, having one can help reduce ground disturbance while digging and make the process a little quicker.

Preset search modes

The ACE 400 comes with 4 preset discrimination patterns and one custom pattern that allows you to save a personal setting. There is also a pre-programmed pinpointing mode that lets you better determine the target’s location, helping to minimize hole size and speed up the process

The available search modes are:

  • Zero (no discrimination)
  • Jewelry
  • Custom
  • Relics
  • Coins
  • pinpoint

Frequently Asked Questions

Is the Garrett ACE 400 waterproof?

The Garrett ACE 400 isn’t fully waterproof. The display and control box is vulnerable to moisture but the search coil is waterproof. This makes the 400 a good option in shallow water and suitable for rainy days with a good cover on your controls.

Is the Garret ACE 400 good for beaches?

The ACE 400 can be used on a beach but the control box isn’t waterproof so be careful around and in the water.

The lack of ground balancing capabilities does hold the ACE 400 back in saltwater and on wet saltwater beaches. For those conditions, you should be looking for a multi-frequency VLF  or a Pulse Induction metal detector for better coverage and discrimination.

How much does the Garrett ACE 400 Weigh?

This detector comes in at a listed 2.9 LBS according to Garrett’s product page. The .1 Lbs increase is caused by the slightly larger coil.

Does the Garrett ACE 300 come with a warranty?

Yes, the ACE 300 is covered under a 2-year limited part and labor warranty provided by Garrett from the date your purchase the metal detector.
Register for your Garrett warranty here >

Videos covering the Garret ACE 400


I always like to check out the manufacturer’s youtube and video resources and Garrett doesn’t disappoint. Just like I noted in my review of the Garrett ACE 300, the team has created an instructional video for the detector giving you a good rundown on the machine. This time the video is in two parts (the second part is below!)

The second part of Garrett’s ACE 400 instructional video series rounds out the two-part series. This video provides details on the 400’s discrimination settings, sensitivity, pinpointing techniques, and some bench testing. Both of these videos provide a brief look at the device in use but are better resources for settings and feature details than anything else.


hreeThe Hoover Boys cover the ACE 400 in a detailed review from a first-person perspective. If you haven’t had the chance to enjoy a Hoover Boy’s video, do yourself a favor and check out their profile for some solid entertainment. These are experienced detectorists and if you’re looking for more opinions on the device, theirs will be worth your time.

Garrett ACE 400 Owner’s Manual Links

If you really like to dive deep with your due diligence before making a purchase, Garret makes it easy to access the user manuals for their devices online. Below is a direct link to see the full details straight from the manufacturer.

Garrett ACE 400 Owner’s Manual Link

Garrett ACE 400 Owner’s Manual Link – Spanish

Final thoughts on the Garrett Ace 400

The Garrett ACE 400 stands out as the metal detector the ACE series was meant to be. While it lacks some high-end features it has everything a beginner needs.

After getting my hands on this device in the field, I could quickly tell why so many of my friends have gravitated toward it. Beating out the ACE 300 with iron audio, a little more power, and a bigger search coil it made sense how it got its reputation.

I recommend the ACE 400 to all beginners searching for their first detector over the Garrett ACE 300 for two reasons:

  • The added feedback on iron targets is a nice quality-of-life addition to a hobby with few cues to help ID finds before digging.
  • The 10 kHz frequency and stock Double-D search coil will help you pick up more targets at a deeper depth.

These two additions help give the 400 a longer lifespan as your initial primary metal detector and will help you have a better overall experience.