Garrett ACE series
Garrett ACE 300 Settings by Site Type: Park, Field, Beach and Old House
Quick answer
There is no single correct setup for a Garrett ACE 300. Run sensitivity as high as the ground will hold without chatter, discriminate only the iron you are certain you will not want, use the adjustable frequency to move off interference, and expect wet salt sand to force sensitivity down further than any other site type.
Settings advice is worth almost nothing without the site attached to it, which is why this page is organised by ground rather than by menu item. The ACE 300 is a single-frequency machine with a numeric 0 to 99 target ID, iron resolution, electronic pinpointing through a non-motion all-metal mode, and an adjustable frequency for interference, which is the full list of levers Garrett publishes for it.
The discipline that separates people who find things from people who swing is simple: change one setting at a time, and give the change a full session before you judge it. What follows is a starting point per site type, and a starting point is all anybody can honestly give you, because your soil is not the soil the next reader is standing on.
Top pick
Garrett ACE 300
Adjustable frequency and iron resolution are the two settings that actually earn their keep on crowded park ground, and the 300 is the cheapest Garrett with both.
Price was accurate when this page was compiled and changes often.
On this page
What should you change first when you arrive at a new site?
Ground noise first, discrimination last. Switch on, hold the coil still at working height, and raise sensitivity until the machine starts chattering with the coil stationary. Back off two steps. That is your ceiling for the day, and it will be lower in wet mineralised ground than in dry sand. Only then do you decide what to reject.
Discrimination is the setting people abuse. Every notch you reject is a decision made before you have heard the target, and on an old site the rejected band is where the best finds hide. Reject small iron if you must. Leave the mid range alone, accept the pull tabs, and dig. If the trash volume makes that impossible, the answer is a smaller coil and a tighter grid, not more rejection. The coil size selector is the honest way to make that call.
What settings suit each site type on an ACE 300?
Treat the sensitivity column as a proportion of the ceiling you established above, not as an absolute number, because the ceiling is a property of the ground.
Wet salt sand is the one site type that forces sensitivity down to roughly half of what dry inland ground will carry, and it is the site type an ACE is least suited to.
| Site type | Sensitivity | Discrimination | Frequency and mode | Coil and sweep |
|---|---|---|---|---|
| Mown town park | High, two steps below chatter | Reject small iron only | Shift frequency if street lighting or another detector is nearby | Stock coil, slow sweep, heavy overlap |
| Sports field, open pasture | Maximum the ground holds | Minimal, accept the tabs | Leave as set unless a fence line interferes | Stock coil, full sweep width, long lanes |
| Old house site, iron heavy | Moderate, iron chatter forces it down | Reject small iron, nothing else | All-metal pinpoint used constantly to size targets | Slowest sweep you can manage, half-width overlap |
| Dry beach, above the tide line | High | Reject small iron | Standard setup, watch for salt chatter at the wet line | Stock coil, grid the towel line |
| Wet salt sand | Low, often near half of inland | Reject small iron | An ACE is a single-frequency machine and salt is its weak ground | Short sweeps, expect false signals |
| Freshwater bank and stream | High | Reject small iron | Coil may be submerged, control box may not | Keep the box high and dry at all times |
| Ploughed field, permission | High | Minimal | Shift frequency away from overhead lines | Work the furrows, not across them |
Every figure here is a starting point expressed relative to your own noise ceiling, not a manufacturer setting. Garrett's manual is the authority on what each control does on your firmware revision.
Why does the ACE 300 struggle on wet salt sand?
Salt water is conductive, so a single-frequency machine reads the ground itself as a target and the operator is forced to give away sensitivity to quieten it. That is a design boundary, not a fault. It is also the reason Garrett's own answer for the beach is elsewhere in the range: the ACE Apex carries a Multi-Salt mode alongside its multi-frequency setting, and the Apex settings page covers how that changes the job. If most of your hunting is surf and wet sand, an ACE 300 is the wrong tool and no setting fixes it.
Inland, the 300 is a different proposition. On dry pasture and park ground a single frequency with a clean target ID is perfectly competitive, and the money you did not spend goes into a pinpointer, a digger and permission-quality boots.
What does electronic pinpointing actually do on this machine?
Garrett lists a non-motion all-metal mode for electronic pinpointing on the ACE 300. Non-motion means the machine will hold a signal without the coil moving, which is what lets you cross the target twice and find the centre. It also sizes targets: a signal that stays loud across a long arc is a big object or several objects, and on an old site that usually means iron you do not want.
Used properly it cuts hole size, which is the part of this hobby that costs people their permissions. Small neat plug, replaced turf, and the farmer lets you back. The ACE 400 settings page covers the same ground for the machine that adds Iron Audio on top.
What supports the machine on a long session?
The ACE 300 runs on AA cells, and a machine with tired batteries changes behaviour before it stops working.
Garrett ACE 300
$269.99Iron resolution and adjustable frequency, at $269.99.
Best for: inland coin and jewellery hunting
Check price on Amazon
Rechargeable AA NiMH Batteries, 8 pack
$10.49Eight NiMH cells at 2,000 mAh, rechargeable up to a thousand times, which is the cheapest running cost fix on an AA machine.
Best for: any AA-powered detector
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Spare AA Battery Holder for Garrett Detectors
$12.99A second loaded holder turns a battery change into a two-second job instead of a kneel in the mud.
Best for: Garrett ACE and AT owners
Check price on AmazonHow we chose
We did not test these machines in person and we publish no find claims. Picks are researched from manufacturer specifications and owner manuals, published listing features, waterproof ratings and warranty terms, and the recurring themes in verified owner reviews. We favour the established detector brands because coils, shafts and control boxes have to stay available years after a model is discontinued, and we place every pick in the tier where its price and capability honestly belong.
Sources
- Garrett ACE 300 owner's manual
- Garrett ACE 300 published feature listing, including adjustable frequency and iron resolution
- Garrett ACE 200 published listing, for the waterproof coil and non-waterproof control box statement
Frequently asked questions
What sensitivity should I run on a Garrett ACE 300?
As high as the ground will carry without the machine chattering when the coil is held still. That ceiling is a property of your soil, not of the detector, so it changes between sites and changes again after rain. Find it at the start of every session, drop two steps, and leave it. Running maximum sensitivity in mineralised ground produces noise that masks the faint deep signals you are there for.
Should I use discrimination on an old house site?
As little as you can bear. Iron-heavy sites are exactly where discrimination throws away good targets, because a non-ferrous object lying next to a nail is often reported as ferrous. Reject small iron if the noise is unworkable, then slow the sweep right down and accept that you will dig more rubbish. A smaller coil helps more than more rejection ever will.
Can I take an ACE 300 into the water?
The searchcoil only. Garrett states the ACE searchcoil is waterproof and can be submerged in shallow water, streams or damp shoreline sand, and states in the same listing that the control box is not waterproof. That is a genuinely different promise from the AT line, which Garrett lists as fully submersible to ten feet. Keep the box high, and do not wade deep with an ACE.
Does changing the frequency help in a crowded park?
That is what Garrett says the control is for: minimising interference from electrical sources or from other detectors in crowded areas. If the machine is chattering with the coil in the air and away from the ground, the problem is electrical rather than mineral, and shifting frequency is the right first move. Reducing sensitivity to cure electrical noise costs you depth you did not need to give away.
How long does a set of AA batteries last in an ACE 300?
Garrett publishes a runtime figure in the ACE owner's manual, and that manual is the number to trust for your machine and firmware. What matters in the field is that alkaline cells fade gradually, and a fading machine loses depth and stability before it shuts off. Carry a second loaded holder and swap on a schedule rather than waiting for symptoms.
Researched, not professional advice. This page is compiled from published specifications, manuals and owner-review consensus, not hands-on testing. Target ID numbers, depth figures and settings vary with soil chemistry, moisture, target size, depth, orientation and firmware version, so treat every figure here as a starting point and verify it against your own machine's manual and your own ground. As an Amazon Associate we earn from qualifying purchases.