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Deal.ai › DS18 › Boat & Car Amplifiers
DS18
DS18 G8400.4D 4-Channel Class D Amplifier

DS18 G8400.4D 4-Channel Class D Amplifier

Best price now

$649.95at Best BuyChecked Nov 8

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Price facts

  • Last seen at $649.95 at Best Buy on Nov 8.

Our take on the DS18 G8400.4D 4-Channel Class D Amplifier

The DS18 G8400.4D is a four-channel Class D car amplifier from DS18's Gen-X line, rated at 400 watts RMS per channel at 4 ohms and stable down to 2 ohms per channel. Class D operation keeps it smaller and cooler-running than the brand's older Class AB amps, so it fits behind a seat or in a compact panel. It suits drivers powering four speakers or a pair of components plus a sub, and it competes with budget four-channel Class D amps on channel count and bridgeability rather than on premium processing. It is a car amp only, not a marine unit.

Best forPowering four door speakers or componentsRunning front components plus a bridged subBudget builds that want Class D efficiencyOwners already using DS18 speakers
Pros
  • Four channels at 400 watts RMS each at 4 ohms
  • Class D design runs cooler and draws less current
  • Stable at 2 ohms per channel for more output
  • Bridgeable to two channels for a subwoofer
  • Compact chassis fits tight install spots
Cons
  • Not rated for marine or boat use
  • No built-in DSP or detailed EQ
  • Power and ground terminals are small for heavy wire
  • Fan noise and heat reported by some owners at high volume

DS18 G8400.4D 4-Channel Class D Amplifier prices at every store

  • Best BuyNew

    In stock

    $649.95Free shippingChecked Nov 8
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Store links may earn us a commission. Price via Klarna.

DS18 G8400.4D 4-Channel Class D Amplifier price history

Lowest price we've seen: $649.95 on Nov 9 at Best Buy. Tracked across 1 store since Nov 9.

What reviewers say

Owner feedback is mixed. People like the output for the size and the low cost of entry, but several report fan noise, heat and short-lived units under hard use.

What people mention
  • OutputPraisedOwners say it delivers plenty of volume for door speakers and bridged subs.
  • Fan noiseCriticisedSeveral owners notice the cooling fan whirring, especially at idle.
  • HeatMixedClass D runs cooler than older amps, but some users report it still gets hot when pushed.
  • ReliabilityCriticisedA number of buyers report units failing or cutting into protection mode.
  • TerminalsCriticisedThe power and speaker connections are described as small and awkward for heavy gauge wire.

Specifications

Color
BlackSource
Suitable for Boats
NoSource
Power Output
RMSSource
Amplifier Class
DSource

Questions and answers

Is this amp stable at 2 ohms?
Yes. Each channel is rated down to 2 ohms, and bridged channels are rated at 4 ohms. Keep speaker impedance within those limits to avoid protection shutdowns.
Can I bridge it to run a subwoofer?
Yes. Bridging pairs of channels gives two higher-power channels for a sub. Check that your sub's impedance matches the bridged rating.
Can I use it on a boat?
No. DS18 lists it as not suitable for boats. Salt, spray and vibration call for a marine-rated amp.
Does it have a built-in crossover or DSP?
It has basic crossover and gain controls, not a full DSP. If you want per-channel tuning or time alignment, a DSP amp is the better fit.
What comes in the box?
The amp, mounting hardware and a basic owner's manual. Wiring and fuses are not included, so plan for an amp kit.
Where is the DS18 G8400.4D 4-Channel Class D Amplifier cheapest?
At Best Buy, for $649.95, as of our latest check.

Stores we've priced the DS18 G8400.4D 4-Channel Class D Amplifier at

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