Philips Sonicare DiamondClean Smart 9750 Review: a premium brush that feels a bit too proud of itself

I’ve been using the Philips Sonicare DiamondClean Smart 9750 in rose gold for a few weeks, after years with a basic Sonicare model and a couple of Oral-B brushes. So I’m not new to electric toothbrushes, but this one clearly sits in the “fancy and expensive” category. Between the app, the pressure sensor, the smart brush head detection and all the modes, it feels more like a gadget than a simple toothbrush at first.

In practice though, it’s still just a tool you use half-asleep in the morning. My main goal was simple: does it clean better than a cheaper Sonicare, and is the extra money actually worth it day to day? I also paid attention to small annoying things: noise, vibrations in the hand, charging, how often I have to change heads, and if the app is something I keep using or just a toy for the first three days.

Right away, the brushing sensation is familiar if you’ve used Sonicare before: high-frequency vibration, not a rotating head like Oral-B. The first time I used it, my teeth did feel very smooth, maybe a bit more polished than with my older model, but it wasn’t some huge difference. The real change is more in the features wrapped around the brushing: light ring for pressure, app guidance, modes, intensities, etc.

If you’re expecting a magic jump in cleanliness compared to any other decent electric toothbrush, you’ll probably be a bit underwhelmed. If you’re coming from a manual brush though, yeah, the step up is clear. Overall, I’d say it’s a high-end brush that works well, but you pay a lot for things that are nice to have rather than strictly necessary.

This is where things get a bit tricky. The DiamondClean Smart 9750 is clearly positioned at the high end, and the price reflects that. You’re paying for the brand, the design, the extra brush heads, the app features, and the fancy charger. If you compare it to a basic Philips Sonicare or even a mid-range model with a timer and a couple of modes, the price gap is pretty big. The question is: do you actually get that much more in daily life?

From my experience, the pure cleaning result is only a bit better than cheaper Sonicare brushes, not dramatically better. The pressure sensor, multiple intensities, and the first-week guidance from the app are the real value adds. But after that, you mostly use it like any other electric brush: 2 minutes, twice a day, rinse, done. The smart stuff becomes background noise. So you’re basically paying a premium for features that are most useful during the first few weeks or if you’re very disciplined about tracking your routine.

Another thing to factor in is the cost of replacement brush heads. The A3 and C3 “premium” heads are not cheap, and since you’re buying into this ecosystem, you’ll keep paying more every few months. If you’re okay with that and you like the idea of always using top-tier heads, fine. But if you’re on a budget, that long-term cost adds up fast and might push the overall value down quite a bit.

Overall, I’d say the value is decent if you really want a high-end, feature-packed brush and you’re actually going to use the app and modes. If you just want clean teeth, a mid-range Sonicare without all the smart stuff will give you 80–90% of the same result for a lot less money. So for most people, this feels like a nice luxury rather than a rational purchase.

Design-wise, this thing clearly aims at the “premium bathroom” look. The rose gold finish looks good in person: not too flashy, more like a soft metallic tone. The handle is slim and feels solid in the hand, with a single main button and a few indicator lights. It definitely looks nicer than a lot of chunky plastic electric brushes, so if you care what sits on your sink, this one doesn’t scream “medical device”.

In practice though, looks don’t brush your teeth. The surface is smooth, almost a bit too smooth. When your hand is wet, it can feel slightly slippery compared to rubberized handles from cheaper models. It never flew out of my hand, but I did have to adjust my grip a couple of times, especially when switching sides. For a product that will constantly be used with water and toothpaste foam, some extra grip would make sense.

The light ring at the bottom is useful: it flashes when you press too hard, and also gives some feedback on modes and pairing. It’s clear and visible in the mirror. The mode selection is done via the same button, cycling through the 5 modes and 3 intensity levels. Once you’ve set it up the way you like it, you don’t really touch it much. During the first few days though, I did accidentally change modes when I just wanted to turn it off, which is a bit annoying but you get used to the timing.

Noise level is reasonable. It’s not silent, but the sound is more of a high-pitched buzz than the grinding rotation noise you get with some Oral-B models. If you share a small bathroom or brush at odd hours, it’s not going to wake up the whole house. Overall, the design looks good and feels premium, but I’d trade a bit of that sleek finish for a more secure, grippy handle.

Battery life is one area where this brush does well. With two 2-minute brushes per day (sometimes three when I remembered to do a quick noon brush), I got a bit over two weeks before the battery indicator started blinking low. That’s in line with what Philips claims and slightly better than my older Sonicare, which usually started complaining after about 10–12 days. So for normal use, you’re not charging it constantly.

The charging glass looks fancy on the counter. You just drop the handle into the glass, and it charges inductively. It’s visually nice, but in practice, it takes up more space than a simple stand. Also, you probably won’t use it as an actual glass for rinsing because it stays plugged in and has contacts at the bottom. So it’s basically a decorative charger. It works fine, I just don’t think the glass concept adds much beyond aesthetics.

For travel, relying only on the internal battery is realistic for trips up to two weeks, as long as you start with a full charge. The travel case in my version doesn’t charge the brush, which at this price point feels stingy. Some older DiamondClean versions had USB-charging travel cases, and that was genuinely useful. Here, if you go on longer trips, you’ll have to bring the charger and hope the hotel has a free outlet near the sink.

Overall, the battery performance is solid, no complaints there. It’s the charging options that feel a bit more style than substance. I’d actually prefer a smaller, simpler charging stand and a USB-powered travel case over the fancy glass. But in terms of pure autonomy, it gets the job done and you’re not constantly worried about it dying mid-brush.

In terms of comfort, the brush heads are on the soft side, which matches the product description. The bristles don’t feel harsh on the gums, even in the higher intensity levels. The first days, I used the medium intensity and the default cleaning mode, and it felt very manageable. If you have sensitive gums, I’d start on the lowest intensity and see how it goes, because the sonic vibration can feel a bit strong if you’ve only used manual brushes before.

The 2-minute timer with 30-second quadrant pauses is standard for Sonicare, and still useful. The brief pause to signal “change area” is clear enough without being jarring. Over time, you get used to the rhythm, and it actually helps not to rush the front teeth and skip the inside surfaces. I never felt like I needed more time; if anything, when I tried the longer or whitening-focused modes, I got a bit bored. For a normal daily routine, the basic clean mode is enough and comfortable.

One thing I noticed: if you push the head too hard against your teeth, the vibration in the handle becomes unpleasant and your arm gets a bit of that buzzing feeling. That’s where the pressure sensor is helpful. The light ring flashes and you instinctively ease off. Once I got used to that, my brushing actually felt more gentle but still effective. Compared to my older Sonicare without a pressure sensor, I did feel less gum irritation after a week or so, probably because I wasn’t grinding the head into my gums.

For daily use, the comfort is solid. It’s not a revelation, but it’s clearly more pleasant than stiff-bristled manual brushes and some cheaper electrics that feel like they’re rattling your skull. If you already like the Sonicare “buzzing” style, this is more of the same, with a bit more fine-tuning thanks to the intensity levels. If you hate that type of vibration, this brush won’t suddenly change your mind.

The “Smart” in the name mostly refers to the Bluetooth connection, brush head recognition, and pressure sensor. On paper, it sounds high-tech: the app tracks your brushing, shows a mouth map, warns you about missed zones, and suggests modes depending on the head you’re using. In reality, it’s helpful at the beginning and then becomes optional once your habits settle.

For the first week, I used the app almost every time. It pointed out that I tended to rush the inner surfaces of my lower teeth and overbrush the front. That feedback was actually useful, and I corrected that after a few days. But after that learning phase, keeping my phone in the bathroom, opening the app, waiting for sync, etc., felt like too much friction for a daily routine. Now I maybe use it once in a while, more out of curiosity than necessity.

The brush head detection works fine: when you snap on a different head, the handle switches to a related mode. For example, the plaque control head might default to a more intense clean. It’s convenient, but not essential. You can always override the mode manually. The pressure sensor, on the other hand, is the one feature that actually changes how you brush. The light ring flashing when you push too hard is very visible, and after a few days, I naturally started using a lighter touch. That’s probably the smartest and most useful part of the whole system.

In daily performance terms, the brush starts and stops reliably, the timer works, and the vibrations are consistent. There’s no weird lag or random disconnect issues that affect brushing itself. The “smart” extras are nice, but if you strip them away, you’re left with a good sonic toothbrush that does its job. Whether the connected stuff is worth the extra cost depends on how nerdy you are about tracking your habits. Personally, I’d say it’s a cool bonus, but not something I’d pay a huge premium for again.

Out of the box, the DiamondClean Smart 9750 feels like a full kit rather than just a handle and a brush head. You get the handle, a few different brush heads (including the A3 Premium All-in-One and the C3 Premium Plaque Control), a charging glass, and a travel case. Depending on the exact pack, the case may or may not charge the brush, so double-check that if it matters to you. Mine came with the glass charger and a USB travel case that doesn’t charge, which is a bit annoying for the price.

The brush heads are clearly positioned as “premium”. They’re slightly larger than some cheaper Sonicare heads and have different bristle patterns. Philips pushes the idea that each head is optimized for something: plaque, gum health, whitening, etc. The handle auto-detects which head is on and switches to a suggested mode, which is a nice touch but not life-changing. I mostly left it on the same mode after a few days because I don’t feel like thinking about it every time I brush.

Pairing with the app is straightforward: you download the Philips Sonicare app, connect via Bluetooth, and it walks you through a guided brushing session. The app shows you zones in your mouth and tries to track where you’re brushing, giving feedback if you miss areas or press too hard. It’s cool for the first week, especially if your dentist always complains you rush the back teeth, but I’ll be honest: after about ten days I started brushing without my phone most of the time. It’s just not realistic that I’ll open an app twice a day forever.

Overall, the package feels complete and “high-end”, but also a bit overdone. You’re paying for the extra heads, the smart features, and the fancy charger. If you just want a simple electric toothbrush, this is kind of overkill. If you like having all the toys and options, you’ll probably enjoy the full bundle, as long as you accept that some of it is more nice-to-have than essential.

Let’s talk about the main point: does it actually clean better? Subjectively, my teeth feel very smooth after brushing with the DiamondClean Smart 9750. When I run my tongue over the front and back surfaces, they feel polished, especially along the gum line. That’s pretty consistent with my experience with other Sonicare models, though. Compared to my old mid-range Sonicare, I’d say the difference is there but not massive. It’s more like a small upgrade than a complete step up.

Where it does help a bit more is around tricky spots. I have a couple of crowded teeth at the bottom, and plaque tends to build up there. After about 10 days with this brush, that area felt slightly cleaner between professional cleanings than with my previous brush. I think the combination of the A3 All-in-One head and the app nudging me to not skip areas did help. But if you don’t actually follow the guidance and just brush on autopilot, you’ll probably get about the same result as any other decent Sonicare.

The whitening claim (removing more stains) is hard to measure without lab tools. I drink coffee daily, and after two weeks my teeth didn’t suddenly look brighter, but surface stains seemed a bit less noticeable. That’s honestly the same result I’ve had with most decent electric brushes when I’m consistent. If you expect your teeth to look like you had professional whitening just from this brush, that’s not realistic.

Overall, in terms of pure effectiveness, I’d rate it as very solid, but not mind-blowing compared to cheaper Philips Sonicare models. If you’re coming from a manual brush, you’ll clearly feel the difference: smoother teeth, fewer spots missed, and probably nicer checkups at the dentist if you stick with it. If you already have a decent electric brush, the extra cleaning performance alone doesn’t fully justify the price; it’s more about the smart features and the comfort add-ons.