Casio Celviano AP-S450 and AP-550 Digital Pianos: Redefining Tradition and Innovation

Fresh from Casio are two digital pianos with several similarities along with some distinct differences. Both also have some unique features that we haven't seen before. Let's take a closer look at the AP-S450 and AP-550.

First, the basics: Both models are designed with the piano experience in mind, so you'll find a total of 26 tones centered around acoustic pianos, electric pianos, organs, and strings. This is mated to a really nice weighted hammer action keyboard, powerful speakers, and the typical dual headphone jacks you'll want for silent practice and recording. They also have the ability to connect wirelessly to your iPad or tablet for learning, adjusting parameters on your piano, viewing sheet music, and more. Pretty standard on this class of digital piano.

Modern and handsome

We set up the AP-S450 first, and upon viewing the finished product, it was pretty obvious that "S" was for "slim." Comparing the AP-S450 to other models in its class, the S450 stands out as being the most compact, slimline premium piano available. Truly, it is designed to fit into the smallest of spaces. You can't do much about the width of a piano, of course, as 88 keys take up the space of, well, 88 keys! But height and depth are two things a builder can work with, and Casio has found some remarkable ways to make this piano compact and still provide a premium hybrid wood keyboard action.

AP-550 - White and AP-S450 - Rosewood in a home setting Closeup of AP-550 lid in open position

They also found a way to house the powerful speaker system in the cabinet with both front firing speakers and two speakers mounted below in two clever vented housings that allow the speakers to sound in all directions. The sound is pretty impressive for such a compact piano.

You can choose from three colors for your AP-S450: classic matte black, a matte white, or a really attractive rosewood that seems a bit brighter and richer than other rosewood pianos we've seen.

The AP-550 takes the cabinet to another level, and looks much closer to other pianos in its class. You'll notice that the legs are more traditional, along with a modesty panel at the rear of the piano to add to the finished appearance. The speaker system is integrated into the cabinet, and Casio is the only piano we know in this price range that has an opening top lid that is not only aesthetically interesting, but it also allows for sound to find its way into the room.

The AP-550 also comes in three color variations (the matte black, matte white, and rosewood).

Both pianos have a nice soft sliding key cover.

Using the piano

When you sit down to play, start by pressing the button mounted on the right side of the piano to power it on. The piano comes to life as the touch display on the left side of the instrument begins to light up. This touch display is where you'll start to do things like change tones, turn the metronome on, or record your performance. A rotary volume control is on the right side. Headphone jacks are conveniently located under the piano, forward, on the left side.

Front view of AP-550 - Black in a home setting Closeup of AP-S450 left-side control panel

Casio opted to streamline the number of buttons on the piano, which means that to change tones, for instance, you will need to touch the Grand Piano button (on the left) and press a corresponding key to change to the tone of your choosing. Often when we see features like this, the builder expects you to memorize what those corresponding keys are. Casio got smart and put a reference label just behind the keys so that you can easily recognize the key you need to press to get your desired result.

Of course, as you would expect with a piano of this caliber, Casio offers a super useful free app called "Casio Music Space" for your iPad (or iPhone) or Android device. This gives you a wonderful visual of all of the settings in the instrument, and you can easily make these changes or hop around to different tones or room settings within the app. As is the case with most instruments, you don't need to have the tablet in order to work the piano, but it just makes it easier.

Dive into the sound

At Kraft Music, one thing you hear us say a lot is something like "dive into the sound and the parameters" of your instrument. Most pianos, when they first turn on, are programmed to sound like a very typical piano tone. But we all have a preference as to how that piano tone should sound. I, for one, like a brighter, rich tone with a lot of reverb on it. We were surprised how much ability Casio included in these instruments to allow you to craft the tone to your liking. Again, this is not an unusual feature for pianos in this class, but we were impressed with the results as we tweaked things like "Hall" (to emulate the sound of playing a piano in a New York Club or Berlin Hall), Surround Type, Brilliance, String Resonance, and Damper Noise. Before long, we had a tone that was vastly different than the stock tone, and one that inspired us to want to continue playing. Again, you can do all this on the piano or you can break out the iPad to get a better visual of the changes you are making. Save the changes within the app, and you can reload your perfectly crafted piano tone each time you play.

Unique feature: Visual Information Bar

We haven't seen this before, and we like it! As you physically approach the piano, you'll notice what looks almost like a mirror – the piano keys reflect on it, giving a nice appearance. But that's not all... when you begin playing, there is a visual bar that appears, mimicking how hard or soft you're playing. Or when you start the metronome, it will pulse and give you a visual of what tempo you have set. I like it, but if you don't, you can easily turn the visual bar off.

Closeup of illuminated AP-S450 Visual Information Bar AP-S450 - Rosewood in a home setting

Unique Feature: Instant RePlayer recording

Also along the lines of things we haven't seen before is Casio's "Instant RePlayer" feature. How often have you played something that sort of comes out of nowhere, and you would like to listen back to what you just amazed yourself with? In comes the RePlayer.

To engage this feature, either activate it from the Casio Music Space app or touch the Function button and the corresponding key on the piano. RePlayer is now engaged, and it will essentially record you as you play. While it is constantly recording, it has memory for just shy of 5 minutes of instant replay. The idea being that you practice and play, and if you want to hear what you just played, you can stop and listen back. How is this different than the standard song record feature found in nearly every piano? Well, in those cases, you are required to press a record button every time you intend to record. Press a button to record; play your song or phrase; press stop; press play and listen back. Don't like what you heard? Repeat the process. With RePlayer, it's always recording so you can play away without bothering to listen back to your mistakes or something uninspiring, but as soon as you've played something that you want to hear, stop and play it back. It's a much more "freeing" way of playing and recording.

Final Impressions

We're very impressed with these pianos! The action is very nice. In fact, at the time of this writing, the AP-S450 is one of the most affordable pianos on the market with a hybrid wood-constructed key action. Our Adam Berzowski commented, "This piano responds very well even when you're playing on the back of the key... not all pianos respond that well regardless of where you are on the key." Going further with the action, Casio says this is one of the quietest actions on the market; we agree. While this might not really affect you, the player, it might be noticeable to others in the home with you as you bang away with your headphones.

As mentioned above, we found the tone to be rewarding and after some relatively quick tweaks, the piano sounded even better than it did out of the box. The Visual Information Bar is a nice modern touch, and RePlayer can be a savior for song writers. Finally, Casio backs up each Celviano piano with a robust 5 year warranty, so you can count on this investment.


  • Smart Hybrid Hammer Action Keys (Celviano Edition) with Spruce construction
  • 26 Tones featuring a new Hamburg grand piano plus a New York variant
  • String & damper resonance, key-off simulation, mechanical sounds
  • Elegant, compact design with sliding soft-close key cover and three fixed pedals
  • Illuminated touch sensor controls that disappear while playing
  • Visual Information Bar displaying metronome beats, key/pedal velocity and more
  • Layer, Split, and Duet Mode capability
  • Four Hall Simulations plus chorus, brilliance, and preset DSP effects
  • Instant RePlayer continuous recorder
  • MIDI & Audio Recorder with USB storage
  • 60-song Music Library with easy learning via the free Casio Music Space app
  • 40-watt, 4-speaker amplification system
  • Dual headphone outputs
  • Class-compliant USB-MIDI plus included WU-BT10 Bluetooth MIDI & Audio Adapter


Above features plus...

  • Elegant cabinetry with sliding soft-close key cover and moveable top lid
  • Included height-adjustable padded piano bench
  • Lid Simulator edit feature in the Casio Music Space