Philips Wake Up Light Review (HF3520)

If you’ve ever heard of wake up lights and are thinking of possibly getting one, congratulations you’ve arrived at the right place! Here I will share my personal experience of using the Philips HF3520 model over the course of a few months.

As for a bit of context about me, I’ve always dreaded mornings and they are by far my least favourite part of the day.
There’s something about being forced out of your peaceful slumber that simply never quite sat right with me.

This said, this also makes me the ideal audience for using a wake-up light since they are supposed to make this procedure easier. But how much of an impact did it actually have?

Before we discuss that, we should first dive a bit deeper into the intended purpose of wake up lights so we know what we should expect from them.


What Wake Up Lights Do

The intended purpose of wake up lights is really quite simple, they are supposed to gently wake you up by creating an artificial light that closely resembles the sun.

The reason for it to resemble the sun is that we are biologically programmed to feel tired or awake depending on the state of the sun. With that said we are able to replicate the effects of our biological responses by artificially simulating the sun in our rooms.

Over the course of a day, the sun goes from a warm yellow/red colour at dawn to a strong blue/white towards the middle of the day and then back to a yellow/red again by dusk.

These “colours“ of light are measured with Kelvin (K). This is the same Kelvin you might stumble across when purchasing light bulbs, where some common values are 2700K or 4000K.

This cycle the sun goes through happens the same way every day and controls the hormones inside of us that control our levels of tired and awake feelings.

This is what the wake-up lights take advantage of and make use of. They will artificially create light that replicates the morning part of the suns cycle to wake us up and set us up for the rest of the day.

The Positives

Now that we know how these lights are supposed to work, I will go through what I found to be the biggest positives about the product. The following points are in no particular order.

The Wake Up Impact

The first thing I’d like to cover is the impact it had on my mornings, which actually impressed me quite a bit. I knew beforehand how these lights function and how theoretically they should cause me to wake up really easily, but I will admit that I was a bit sceptical going into it.

I usually find it difficult to fall asleep, but when I do I sleep so heavy to the point where literal thunderstorms won’t wake me up, so I found the idea of a bit of artificial light in my room waking me up gently a bit far-fetched. That said, it actually surpassed my expectations by quite a bit.

Over the course of using the wake-up light, it actually managed to wake me up in a pretty non-intrusive way most of the time.

Since starts out at a warm red and gradually transforms into a brighter white light (like the sun) it doesn’t feel as intrusive as a regular alarm or somebody else waking you up.

However, this could also be due to the settings I set mine to. I tested out a few different brightnesses and found that a few on the stronger end were simply way too much for me in the morning, but after lowering it to a milder brightness it became bearable and quite pleasant to wake up to.

Intuitive Interface

Another thing I quite enjoyed about this wake-up light is that I found the interface of it to be quite intuitive.

The first time I tried using it, I was admittedly confused since there aren’t any buttons that directly signify left or right, but once I understood that the plus and minus signs acted out that function, it became easy to navigate it.

That said though, they aren’t actually buttons in the traditional sense. They are actually just touch-sensitive areas on the face of the lamp.

Using these “buttons“ you can change the settings of a few different things, such as the time of the clock, the time of the alarms and the brightness of the display.

While the front of the light has no buttons there are actually buttons placed across the edge on the top of the lamp.

These buttons are also very intuitive as they are grouped up sensibly and have icons that are easy to understand.

There are about 10 buttons on the outside. These buttons can change the brightness of the light and the volume of the sound coming out of the back.

These buttons make it very easy to change settings as you please since pressing the buttons will cause the function to activate as well as enabling you to edit the specific function.

For example, when you press the light button it will simply light up to the last used strength.
From this moment you can press the plus or minus button to change the strength and subsequently the colour of the light.

On a side note, this function in particular also enables you to use this light as a reading light if you so wish since the light doesn’t actually shut off unless you press the button again.

Reading books isn’t exactly my cup of tea but if you’re someone who reads a lot this can definitively be a strong point of consideration.

Two Different Programmable Alarms

Something else I found pretty handy with this light is that it has two separate alarms, which you can individually program for light strengths and time.

I liked this because it allowed me to have two separate alarm times, one for weekdays and one for weekends, since I tend to not want to wake up as early on the weekends They are easy to switch between since they are selected using the physical buttons on the edge of the light.

This also means that you theoretically can use both alarms at once if you felt like it, not that I personally see any particular use of that ability.

Nonetheless, this was a nice feature that I wanted to address.

Bird Chirping Noises

The last thing I’d like to mention is the soothing bird chirping noises it makes as your alarm is going off. It does this in order to emphasize the morning feeling you’re supposed to get through the light.

I found this to be very effective. It made me feel totally immersed in a summer morning feeling where the light shines bright on you and you hear the birds chirping in the background.

It was in fact so effective that I didn’t even realize it came from the light at first. I live in a pretty wooded area where there are naturally a lot of birds around, so I’m pretty used to the sound of birds in the mornings. Because of this, I didn’t actually suspect that the noise came from the light since the sound is so natural to me already.

Personally, I find that detail quite funny, but it also speaks for how well integrated those sounds are into the light.

The Negatives

Now that we’ve gone over most of the positives we should address some of the negatives of it in order to have a full picture of how good this light in particular is.

The Button Placements

For me personally, the placement of the buttons are a bit inconvenient.

They are easy to navigate since they are labelled, however, unless you’re actually looking straight down to the buttons and see the markings it is awfully difficult to navigate them unless you memorized where each button is and what its corresponding function is.

This becomes extra problematic when you factor in that most of the time you’ll be changing settings the night before using it, which means that it is most likely dark. This makes it quite difficult to navigate the buttons, which is something I personally experienced and did not particularly appreciate.

Non-Replaceable LED Light

Another part of it that is not quite ideal is that the LED light inside of it is not actually replaceable. This is quite unsustainable for regular household usage, since when it breaks you have to buy a new one due to the light being irreplaceable in the same light fixture.

That said, it is also only warranted to last for a few years, which means that you might have to replace it quite often if you’re unlucky. I’m lucky enough to have had mine last for the entire time of my use, but I’ve read several product reviews where it’s been documented to fail or break prematurely.

Despite this though it is possible to have it last for a long time as well. I personally think that the lifespan of it boils down to how well the product was handled before it came into your possession and how well you take care of it, but it can break due to failures unrelated to both.

Awkward Shape

I don’t know if this will be a problem for most people, but for me, the general shape of the light just feels kind of awkward. The design itself is nice and it looks good, however, to me it is just kind of bulky and takes up a lot of space on the nightstand.

This can of course depend on the size of your nightstand. My current one isn’t that big, which is why I bring this up as an issue. This said, if you have a big nightstand I wouldn’t worry about this, but if your space is limited like mine I would at least bring this into consideration.

Sub-Par Radio

Something I read on plenty of product reviews of the wake-up light is that the radio function of it isn’t exactly up to par in comparison to your regular radios, so I decided to try it out myself.

As most reviews claim this is sort of true, while the radio sound is a bit off to regular radios I’d still say it’s pretty okay. It’s neither great nor terrible in my opinion.

This said, I personally believe that you’re doing the light quite the disservice by using the radio function instead of the bird noises. The birds just make your mornings feel more alive and I can’t see why you’d choose radio over them, but that is of course your choice to make.


So, after going through all the main positives and negatives of the product, would I recommend it? I would say that I probably would. It has been pretty solid over the course of using it.

If you want to check it out directly on the Philips website I will link it to you here. This said I want to go over some of Philips other available options. (It is also worth noting that at the time of writing this the product is unavailable on the website.)

Since we’ve concluded that there are a few flaws with this model in particular I want to see if any of their other models improve on these factors and I believe to have found their best wake-up light based on these parameters.

Here I’d like to introduce the HF3650 model. When looking at it and reading its reviews it seems to me like this model of wake up light improves on the qualities that the HF3520 lack.

According to the reviews on the website, it appears that the radio quality seems to have improved quite a bit and that it has a lot more customizable options available. It is also worth noting that this model has an aux input on it, meaning that you could hook your phone up to it and use it as a speaker.

While it is still not super sleek, it is also not as bulky as the HF3520 is either, which is a huge plus in my opinion.

Also, while functionality is of course more important than the looks, I need to say that this model simply looks a lot cooler than the HF3520 does.

The main issue that users seem to have with it is that the display and buttons aren’t as user friendly as the HF3520. That said, it does come with a manual that explains how to operate it in more detail, but I suppose that the absence of physical buttons will cause some confusion in programming and setup.

That seems to be it though as for the common negatives about the product. So, if you feel confident in your ability to understand the interface and setting it up I would definitely recommend that you check out the HF3650 on the Philips website.

Technical Specifications Of HF3520

NOTE: This information was collected directly from the Philips website.

General Specifications

  • Anti-slip rubber feet: Yes

  • Snooze type: Smart snooze

  • Display brightness control: Self-adjusting

  • Instore demo function: Yes

  • Number of alarm times: 2 alarms

  • Tap snooze for sound: 9 minutes

  • Charges iPhone/ iPod Touch: No

  • Controlled by iPhone/ iPod App: No


  • UV-free: Yes


  • FM radio: Yes

  • Number of Wake-up Sounds: 5

  • Music from smartphone / iPod: No

Well-being by light

  • Increase alertness: Yes

  • Drift to sleep naturally: Yes

  • Wake up naturally: Yes

  • Wake-up gradually: Yes

Natural light

  • Brightness settings: 20

  • Coloured sunrise simulation: Yes. Red, to orange to yellow.

  • Light intensity: 300 Lux

  • Sunrise simulating process: adjustable 20-40 minutes

  • Sunset simulation: Yes

Technical specifications

  • Cord length: 150 cm

  • Frequency: 50/60 Hz

  • Insulation: Class III

  • Insulation Power plug: Class II (double isolation)

  • Power: 16.5 W

  • Power Output Adapter: 12W

  • Type of lamps: Lumiled Luxeon Rebel

  • Voltage: 100/240 V

  • Time backup: 4 to 8 hours

Weight and dimensions

  • Country of origin: China

  • Power Plug weight: 99 gram

  • Product dimensions: 19.2 (height) x 19.9 (diameter) x14.6 (depth) cm

  • Product weight: 730 grams