Product · PHILIPS
Sonicare DiamondClean Smart 9400: brush head detection, app
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The DiamondClean Smart 9400 is a long-running Sonicare flagship that suits people who want app guidance and a choice of heads straight out of the box. Where many premium sets ship one general head, this bundle includes both an A3 Premium All-in-One and a G3 Premium Gum Care head. The title also mentions brush head detection, so the handle can recognise which head is fitted, though the bullets do not explain how that changes the clean.
- Gentle or sensitive setting
- 3 intensity levels
- Intensity levels
- 3
- Pressure feedback
- Light ring flashes
- Modes
- 4
In its favour
- Four brushing modes and three intensity levels, with a light ring on the handle that flashes if you press too hard.
- The box includes two heads (A3 Premium All-in-One and G3 Premium Gum Care), a charging glass and a USB charging travel case.
- Brush head detection is listed in the title, and the handle connects to the Philips Sonicare app for brushing guidance.
Good to know
- The listing does not give a battery figure in days, so you cannot plan trip length from the page alone.
- There is no SenseIQ automatic intensity reduction here; that feature is reserved for the Prestige models in this range.
Our take
Modes and intensity
Philips lists 4 brushing modes and 3 intensity levels. The three steps of intensity are the main comfort control here, so a sensitive mouth can drop to the lowest level in any mode.
The listing repeats Philips' claims of up to 20 times more effective cleaning with the same brushing and up to 15 times healthier gums, both footnoted as manufacturer figures.
Pressure light and app guidance
A light ring at the end of the handle flashes when you use too much pressure. There is no automatic intensity reduction described, so this model relies on you noticing the light and easing off.
Connecting to the Philips Sonicare app gives personalised brushing guidance. The listing does not mention a display on the handle, so detailed feedback lives in the app rather than on the brush.
Box contents and charging
The set includes the handle, the A3 and G3 heads, a charging glass and a USB charging travel case. Philips notes a UK two-pin bathroom plug and a two year manufacturer warranty.
The charging glass is a feature some owners love for the look on a shelf, while the USB case lets you top up from a laptop or a hotel USB port. Battery life is not stated.
How it compares
The Sonicare DiamondClean 9000 offers the same 4 modes and 3 intensities, a quoted 14 days of battery and a USB travel case, but ships with one C3 head and a charging stand instead of the glass. The Sonicare 7900 swaps the premium heads for four W2 Optimal White heads and uses a pulsing handle as its pressure alert.
Verdict
The 9400 is a good match if you want both an all-round head and a gum care head included, app guidance, a charging glass and a USB travel case. If a stated battery figure matters, the DiamondClean 9000 is better documented, and if you mostly want whitening heads in bulk, the Sonicare 7900 is the alternative.
Compared with alternatives in: Best electric toothbrushes with gentle modes and pressure sensors, Best electric toothbrushes with a charging travel case, Best electric toothbrushes under £300, Best electric toothbrushes in the UK: premium models compared, Best smart toothbrushes with an app, Best sonic electric toothbrushes, Philips Sonicare models compared: DiamondClean 9000, Smart and Prestige
Amazon listing title: Philips Sonicare DiamondClean Smart 9400 Electric Toothbrush, Sonic Toothbrush with App, Pressure Sensor, Brush Head Detection, 4 Brushing Modes and 3 Intensity Levels, Black, Model HX9917/89