Casio PX-870 vs Kawai KDP120

Choosing between the Casio PX-870 and the Kawai KDP120 isn’t as simple as picking the shinier cabinet or the bigger speaker wattage. These two digital pianos land in the same general price range and both promise an authentic playing experience, but they take different roads to get there. The PX-870 leans on Casio’s reputation for feature-packed, tech-savvy instruments that fit seamlessly into modern lifestyles. The KDP120 carries Kawai’s legacy of building rich, expressive acoustic pianos and translating that nuance into digital form.

On paper, they’re both full-sized, furniture-style pianos with weighted keys, quality sound engines, and decent speakers. In practice, their personalities couldn’t be more distinct — one is a Swiss army knife, the other is a single, beautifully honed blade. In this review, we’ll break down every aspect — design, keyboard feel, sound, speakers, functions, connectivity, and value — to help you decide which better fits your music and your space.

Casio PX-870 vs Kawai KDP120 Comparison Chart

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Feature / Spec	Casio PX-870	Kawai KDP120
	Check the best price on Amazon	Check the best price on Amazon
Keyboard Action	Tri-Sensor Scaled Hammer Action II; simulated ebony/ivory key surfaces; 3 touch levels + fixed	Responsive Hammer Compact II; graded hammer weighting; matte keytops; 3 touch levels + fixed
Keys	88 fully weighted	88 fully weighted
Polyphony	256 notes	192 notes
Sound Engine	Multi-dimensional Morphing AiR, 19 tones	Harmonic Imaging (SK-EX samples), ~15 sounds
Effects & Resonance	Hall Simulator, chorus, brilliance, damper/string/key-off simulations, Volume Sync EQ	Reverb; Virtual Technician Lite; damper resonance
Speakers & Output Power	2 × 20 W (20 W + 20 W), total 4 speakers (12 cm × 2 + 4 cm × 2)	2 × 20 W stereo speakers; bass reflex system
Pedals	3 built-in: damper (half-damper), sostenuto, soft	“Grand Feel” pedal system: damper (half-pedal), sostenuto, soft
Lesson & Built-in Songs	60 built-in pieces + 10 user songs; Concert Play mode	Built-in etudes (Alfred, Burgmüller, Czerny, Beyer); 55 demo songs
Recorder	2-track MIDI; Audio (WAV) to USB flash drive (up to ~25 min/song)	3-song MIDI recorder (~10,000-note memory)
Connectivity	USB-A for memory, USB-B MIDI, Bluetooth Audio streaming, line outs, dual headphone jacks (¼″ & ⅛″)	USB-B MIDI, Bluetooth MIDI (BLE), dual headphone jacks, line outs, PianoRemote app support
Dimensions (W × D × H)	~1393 × 299 × 801 mm (~54.8″ × 11.8″ × 31.5″)	~1360 × 405 × 855 mm (~53.5″ × 16″ × 33.5″)
Weight	~34.3 kg (~76 lb)	~37 kg (~81.5 lb)
Included Accessories	Music stand, AC adapter, console stand, triple-pedal unit	Matching bench, music rest, AC adapter, triple-pedal unit
Warranty	Typically 1 year (region-dependent)	3-year manufacturer warranty (in some regions / retailers)
My individual reviews	Casio PX-870 review	Kawai KDP120 review

First Impressions & Design

If you’ve ever walked into a music store or browsed through glossy product shots online, you know that the first thing you notice about a piano — digital or acoustic — is how it looks and how it sits in a room. “First impressions” in the context of digital pianos aren’t just about vanity; the design speaks volumes about the manufacturer’s intentions. It hints at who they built it for, whether they wanted it to blend into a modern apartment, dominate a formal music room, or become a chameleon that works in both. The Casio PX-870 and the Kawai KDP120 are perfect examples of how two companies can approach this same “home piano” segment from very different design philosophies.

Casio PX-870 design language

The PX-870 belongs to Casio’s Privia line, which has built a reputation for sleek, modern, and space-conscious digital pianos. Right out of the box, the PX-870 gives off a “refined minimalism” vibe. The lines are straight and purposeful, the corners are slightly softened, and nothing feels bulky or ornamental. Its cabinet depth is relatively slim, which is great if you’re working with a smaller apartment or studio. The overall weight is lighter than many full-sized furniture-style digitals, and that translates to easier assembly and the possibility of moving it around without hiring three friends and bribing them with pizza.

Casio offers the PX-870 in finishes like black, white, and a rich walnut, each with a matte surface rather than a high-gloss sheen. That matte texture hides fingerprints and dust far better than a polished finish — a small but appreciated practical win. The design integrates the control panel under the left side of the keyboard, which means you can keep the aesthetic clean when you’re not tweaking settings. It’s the kind of layout that blends into a living room and doesn’t scream “I’m a digital instrument with fifty buttons.”

Another design highlight is the keyboard lid. Casio uses a sliding key cover that doubles as a music rest when flipped up. It feels solid, glides smoothly, and offers a layer of protection against dust or curious small fingers when not in use. The hinge mechanism is firm enough to feel premium but light enough to open with one hand.

The PX-870 sits on a matching base with a fixed three-pedal unit at the bottom. While the stand isn’t as substantial as something you’d find on a premium upright, it’s sturdy enough to avoid wobble under normal play. The pedal bar feels connected to the frame rather than an afterthought — no annoying sway or creak when you press down.

Overall, the PX-870’s design is forward-looking but restrained. It’s a digital piano that can pass as stylish furniture in a modern loft but won’t feel out of place in a traditional music room.

Kawai KDP120 design language

The KDP120 approaches design with a different philosophy: tradition first, digital second. If the Casio is a slim-fit suit, the Kawai is a tailored classic blazer — more material, more presence, more formality. It has a thicker cabinet profile, which instantly makes it feel more like a piece of traditional furniture than a gadget. This bulk isn’t purely aesthetic; it contributes to a more solid playing feel and can help with acoustic projection.

The finishes available — typically satin black, rosewood, and white — lean into the acoustic piano tradition. The surfaces are smooth and elegant, though slightly more prone to showing fingerprints compared to Casio’s matte. The cabinet sides are straight but wider, and the front panel has a cleaner face with fewer visible buttons. The control buttons are recessed and accompanied by a physical volume knob, which makes quick adjustments simple without cluttering the look.

The music rest is a separate, folding panel that sits on top of the cabinet rather than being part of a sliding key cover. This rest is generous in size and can easily hold larger sheet music books or tablets. The downside: the keys are always exposed unless you use a separate dust cover. Some players prefer this — it’s always ready to play, like an acoustic upright — while others might miss the sliding cover for dust and accident prevention.

The pedal unit on the KDP120 is integrated into a thicker, heavier base than the PX-870’s. It feels solid and planted, almost like it’s bolted to the floor. This sturdiness adds to the “real piano” illusion, especially for players who use pedals expressively and with a bit of force.

Because the KDP120 is heavier overall, it feels more stable during energetic playing. However, that weight also means you won’t be casually moving it around once it’s in place. This is a piano you set up in one spot and leave there.

Comparing form and function

Both pianos are clearly designed to fit into domestic spaces, but they lean toward different environments. The PX-870’s slim footprint makes it easier to fit into tight corners, bedrooms, or home studios without eating up too much floor space. Its finishes and sliding lid make it well-suited to multipurpose rooms where you might want to “hide” the instrument when not in use.

The KDP120’s traditional presence means it thrives in dedicated music rooms, formal living rooms, or anywhere you want the piano to be a focal point. It looks more like a “real” acoustic upright from a distance, which can be appealing if you want that visual impact. The trade-off is that it takes up more space and feels more like a permanent fixture.

In terms of durability, both cabinets are well-built for their price range, but the KDP120’s heavier structure may give it an edge in withstanding years of use without loosening joints or developing creaks. That said, Casio’s cabinet still feels sturdy, and its lighter weight can be a benefit in homes where you may eventually need to relocate it.

User interaction and ergonomics

Design isn’t just about how a piano looks — it’s also about how you interact with it. On the PX-870, the hidden control panel keeps things clean but can make it a bit trickier to operate without looking. You’ll eventually memorize button positions, but there’s a small learning curve. The KDP120’s more visible (though still minimal) controls and dedicated volume knob make on-the-fly adjustments easier.

The music rest design also affects ergonomics. Casio’s integrated rest feels stable and can be adjusted by flipping it up or down, but it’s limited in angle. Kawai’s separate folding rest has a slight backward lean that’s more comfortable for reading sheet music over long practice sessions.

Finally, pedal feel is a small but important detail. Both offer a three-pedal configuration, but Kawai’s heavier base and pedal resistance feel closer to an acoustic piano, while Casio’s slightly lighter action may suit beginners or those who prefer less pedal resistance.

Visual harmony in different settings

Imagine the PX-870 in a small city apartment: the slim depth keeps it from overwhelming the room, the matte finish blends with modern furniture, and the sliding cover hides the keys when the dining table is nearby. Now imagine the KDP120 in a suburban home’s formal living room: the heavier cabinet and rich finish stand proudly in a corner, looking every bit like a traditional upright ready for an evening recital.

Neither approach is “better” in a vacuum — it depends entirely on your space, style, and how much you want your piano to command attention versus blend in.

Keyboard & Action Feel

The feel of a digital piano’s keyboard is one of the most decisive factors for most buyers. While sound can be shaped with headphones, external speakers, or software, the physical touch of the keys is something you can’t really upgrade later. It influences how you play, how much control you have over dynamics, and even how long you can practice without fatigue. This is where the Casio PX-870 and the Kawai KDP120 part ways in their approach, each aiming to capture an acoustic piano’s experience in its own way.

Casio PX-870 key action

The PX-870 uses Casio’s Tri-Sensor Scaled Hammer Action II. The name sounds technical, but in plain terms it means the keyboard uses three sensors per key to capture nuances in how fast and how hard you press. This allows the instrument to detect repeated key strikes more precisely, even if the key hasn’t fully returned to the top position. That’s especially handy for fast passages, trills, and ornamentations where you need every note to register cleanly.

The “Scaled Hammer” part refers to the weight distribution across the keyboard — heavier in the bass, lighter in the treble — mimicking the way an acoustic piano’s hammers behave due to string thickness and hammer size. This graduated feel is noticeable without being exaggerated. In the lower octaves, you do feel more resistance, which can help with phrasing and dynamic control.

Casio has also added simulated ivory and ebony textures to the keys. These aren’t just visual — the matte, slightly porous surface provides a better grip, particularly when your fingers get a little sweaty during long practice sessions. It’s a subtle detail, but it makes the PX-870 feel more premium and less “plasticky” than some other digitals in its price range.

One potential downside for some players is that the PX-870’s action is on the slightly heavier side compared to other digital pianos in this bracket. For seasoned pianists, this can feel satisfyingly solid and close to an acoustic upright. For beginners or players with smaller hands, it might require a bit more strength, especially for extended practice sessions.

Kawai KDP120 key action

The KDP120 is equipped with Kawai’s Responsive Hammer Compact (RHC) action. This is a scaled-down version of the key action used in Kawai’s higher-end digital and hybrid models. It uses two sensors instead of three, which means repeated note detection is slightly less instantaneous compared to the Casio. However, in practice, most intermediate players won’t notice a big difference unless they’re playing extremely fast repetitions or very advanced repertoire.

The RHC action has a slightly lighter touch overall, which makes it more forgiving for long playing sessions. Beginners often appreciate this, as it allows them to focus on finger independence and musical expression without fatigue setting in too soon. The lighter action also makes it easier to play softly, though some advanced players might prefer a bit more resistance for control in louder passages.

Kawai opts for smooth keytops rather than textured ones. This gives a polished, almost glassy feel under the fingers, which some players love for its fluidity. Others may find it a bit slippery compared to Casio’s textured keys, especially in warm or humid environments. It really comes down to personal preference here.

Like the PX-870, the KDP120 features graded hammer weighting, so the bass keys feel heavier and the treble keys lighter. The weighting is subtle but effective, and combined with the smooth action, it creates a playing experience that’s easy to adapt to, even for those transitioning from lighter keyboard instruments.

Comparing responsiveness

The main distinction between these two key actions comes down to responsiveness in advanced playing. The PX-870’s triple sensor system offers more accurate detection for rapid note repetition and fast passages, especially when a key isn’t fully released between strikes. This is something you’d notice in pieces with repeated staccato notes, fast scales, or intricate ornaments.

The KDP120’s dual sensor action is still responsive, but you might need slightly cleaner finger technique to get the same accuracy on repeated notes. In exchange, its lighter touch can feel faster for some players, particularly in legato passages where you want minimal resistance.

Noise and mechanical feel

Both pianos do a good job of keeping mechanical noise to a minimum. The PX-870’s action produces a quiet, muted thud when keys bottom out, which is barely noticeable unless you’re playing without any sound. The KDP120 is similar, though its lighter action produces slightly less “thunk” on heavy strikes.

Neither has the wooden keys or advanced pivot points of much higher-end models, but they’re both well-built for their class. The PX-870’s slightly firmer feel makes it seem more substantial under the fingers, while the KDP120’s lighter action may feel a bit less grounded to players used to grand pianos.

Adjustability and touch curves

One area where digital pianos differ from acoustics is in touch sensitivity settings — the ability to adjust how the instrument responds to your playing strength. The PX-870 offers multiple touch curve settings, from light to heavy, so you can tailor the feel somewhat to your preference. While this doesn’t change the physical resistance of the keys, it alters how the sound engine reacts to your dynamics.

The KDP120 offers similar touch curve adjustments, though its lighter baseline feel means even on the heaviest setting it won’t feel as weighty as the Casio. This flexibility is useful if you want to match the response to a particular repertoire or to your own playing style.

Long-term comfort and fatigue

If you tend to play for hours at a time, the difference in action weight will matter. The PX-870’s heavier touch builds finger strength but can also lead to fatigue faster, especially if you’re not accustomed to it. It’s a bit like training with a heavier racquet in tennis — great for building muscles, but potentially tiring for casual play.

The KDP120’s lighter action makes it easier to keep going during extended practice. It’s less demanding physically, which is a plus for beginners, older players, or anyone recovering from hand or wrist strain. On the flip side, it may not challenge your muscles in quite the same way.

Acoustic realism

When comparing to an acoustic upright or grand, the PX-870’s action feels closer in weight and resistance, though not as refined in terms of pivot depth and repetition speed as high-end digitals or hybrids. The textured keytops help simulate the tactile experience of ivory/ebony surfaces, which can subtly influence finger confidence during difficult passages.

The KDP120 leans toward accessibility over strict realism. The smooth keytops and lighter feel make it a very playable instrument for a wide range of skill levels, but advanced classical pianists may notice the difference when moving back to a real grand. That said, for many players, its balance of lightness and graded resistance is more comfortable for daily practice.

Who each key action suits best

If you’re a classically trained pianist, or you’re aiming to develop strong, controlled technique for advanced repertoire, the PX-870’s Tri-Sensor Scaled Hammer Action II will probably feel more rewarding. Its heavier resistance, textured keys, and triple sensors make it the more “serious practice” option.

If you’re newer to piano, or you value long, fatigue-free sessions over strict acoustic realism, the KDP120’s RHC action might be more comfortable. It’s also a better match for those who prioritize smooth key travel and a slightly lighter touch.

In the end, neither action is objectively better — they’re simply tuned for different kinds of players. The PX-870 is like a well-calibrated training instrument, pushing you closer to the feel of an upright or grand. The KDP120 is like a friendly, welcoming teacher, making sure you feel at ease every time you sit down to play.

Sound Engines & Tone Quality

While keyboard feel determines how you interact with a digital piano, the sound engine defines what you hear in return. It’s the voice of the instrument — its character, expressiveness, and realism all stem from how well it can reproduce and shape the sound of an acoustic piano (and other instruments, if included). Both the Casio PX-870 and Kawai KDP120 aim to offer an authentic, immersive sonic experience, but their design philosophies and technological approaches produce very different results.

Casio PX-870 sound engine

The PX-870 is powered by Casio’s “Multi-dimensional Morphing AiR Sound Source.” It’s a long name for a system designed to do two main things: capture high-quality piano samples and make the transitions between dynamic levels smooth and natural. Instead of simply switching from one velocity layer to another when you play harder or softer, the AiR engine “morphs” between them, creating a continuous shift in tone and volume.

The main piano voices are sampled from a concert grand, with multiple velocity layers and resonance modeling. Casio has included sympathetic string resonance, damper resonance, and key-off simulation. This means when you hold the sustain pedal, other strings vibrate in response to the ones you play, and when you release a key, you hear the subtle thud and decay you’d expect from a real piano. These details don’t dominate the sound, but they contribute to a more believable playing experience.

The PX-870 offers 19 built-in tones, ranging from various acoustic pianos to electric pianos, organs, strings, harpsichords, and more. While it’s not a “workstation” with hundreds of sounds, the palette is broad enough for variety in practice and casual performance. Many players enjoy layering strings with the grand piano voice for cinematic textures, or switching to an electric piano for pop and jazz standards.

Casio’s tonal character tends to lean toward the bright and clear side of the spectrum. The attack of each note is well-defined, with crisp articulation that helps melodies cut through. This clarity is an asset in dense arrangements or when playing in a band, but some solo pianists might find it a little less warm than they prefer for romantic or impressionist repertoire.

Kawai KDP120 sound engine

The KDP120 uses Kawai’s Harmonic Imaging sound technology, which focuses on reproducing the tone of Kawai’s flagship SK-EX Concert Grand. Unlike Casio’s morphing approach, Harmonic Imaging samples each note of the piano at multiple dynamic levels and emphasizes tonal richness and depth. The goal is to make the piano sound warm, resonant, and “alive” even in soft playing.

Kawai’s tone is generally fuller in the midrange, with a slightly darker overall profile than the Casio. This warmth makes it especially appealing for classical and jazz repertoire, where you want body and roundness in every note. Harmonic Imaging also integrates resonance modeling, so sympathetic vibrations and damper resonance are present, though the overall effect is more blended and less overt than on the PX-870.

The KDP120 offers a smaller sound set — about 15 voices total. These include variations of acoustic pianos, electric pianos, organs, strings, and a harpsichord. While the variety is more limited, the flagship SK-EX grand piano sound is clearly the star of the show. The default concert grand voice has a depth and expressiveness that makes you want to linger on chords and savor the sustain.

Comparing tonal character

The PX-870 and KDP120 both aim to recreate the feel of an acoustic piano, but they do so with different tonal personalities.

The PX-870 is like a bright, well-maintained grand in a lively room — its notes have a certain shimmer that stands out in mixes and brings energy to pop, gospel, or upbeat classical pieces. Its brightness also means the high registers sparkle and sing, which can be inspiring when playing intricate treble melodies. However, if you prefer mellow tones, you might need to adjust EQ or use softer touch curves to tame the brightness.

The KDP120, by contrast, feels like a concert grand in a warm recital hall — rich, rounded, and resonant. The sound has more body in the mids and lows, making it excellent for solo playing where you want the piano to fill the space without being sharp or piercing. On the flip side, this warmth can sometimes make the tone feel a little more blended and less cutting in busy arrangements.

Dynamic range and expressiveness

Dynamic range refers to how convincingly the piano can move from the softest pianissimo to the loudest fortissimo. Both instruments perform well here, but the PX-870’s triple sensor action combined with its morphing sound engine gives it a slightly more pronounced shift in tonal character as you play harder or softer. This can make crescendos feel more dramatic and staccatos more biting.

The KDP120’s strength lies in subtlety. Its dynamics are smooth and organic, with a natural bloom to sustained notes that encourages expressive phrasing. Soft passages, in particular, are more velvety and intimate than on the Casio, which tends toward clarity and precision even at low volumes.

Polyphony

Polyphony — the number of notes the piano can sound at once — matters for layered sounds, sustained passages, and complex pieces with pedal use. The PX-870 boasts 256-note polyphony, which is more than enough for practically any repertoire, even with layered voices. The KDP120 offers 192-note polyphony, still very capable but slightly less future-proof if you use layers heavily.

In real-world playing, both handle demanding pieces without notes cutting out, but the extra headroom on the PX-870 may appeal to those who use lush layers and sustain extensively.

Onboard effects and customization

Casio equips the PX-870 with multiple reverb types (Room, Small Hall, Large Hall, Stadium, etc.) and chorus settings, allowing you to tailor the ambience to taste. You can also adjust brilliance, which brightens or darkens the overall tone. These options make it easy to adapt the sound to different musical styles or environments.

The KDP120 offers fewer ambience variations but includes its “Virtual Technician Lite” function, which lets you tweak aspects like damper resonance, voicing, and touch curve. While not as extensive as the full Virtual Technician found in higher-end Kawais, it still provides enough customization for most players who want to fine-tune their tone.

Playing through headphones

Headphone performance can make or break a digital piano for apartment dwellers and late-night players. The PX-870 includes Casio’s “Headphone Mode,” which optimizes the sound for binaural listening, adding depth and spatial placement that feels more like sitting in front of an acoustic piano. It’s impressive, especially with high-quality headphones, and makes long practice sessions more enjoyable.

Kawai has its own approach to headphone optimization, and the SK-EX sample really shines in this context. The warmth and sustain come through beautifully, and the tonal body prevents the sound from feeling thin or artificial. If anything, Kawai’s tone can feel even more immersive in headphones because the blend and warmth mask some of the “digital edges” that headphones can reveal.

Projection through built-in speakers

We’ll go deeper into speakers in the next section, but it’s worth noting here that the sound engine’s output is affected by the speaker design. The PX-870’s brightness is well-served by its clear, forward-facing projection, while the KDP120’s warmth benefits from the fuller bass provided by its dedicated low-frequency driver.

Who each sound suits best

The PX-870’s sound engine is ideal for players who want versatility, brightness, and clarity. It’s well-suited for modern genres, ensemble settings, and situations where the piano needs to cut through. It also gives you more tonal variety thanks to its extra voices and EQ controls.

The KDP120’s Harmonic Imaging engine caters to pianists who value warmth, depth, and a rich solo playing experience. It’s particularly strong for classical, jazz, and ballads — any style where you want the piano’s tone to envelop the listener rather than stand out sharply.

In short: the PX-870 is the lively conversationalist at a party; the KDP120 is the warm storyteller in a quiet room.

Built-In Speaker Systems

Speakers in a digital piano aren’t just about raw loudness — they shape the entire playing experience. The right speaker system brings the sound engine to life, giving you the resonance, depth, and projection that make a digital piano feel more like an acoustic instrument. Conversely, a weak or poorly tuned system can make even the most detailed samples sound flat and uninspiring. In the case of the Casio PX-870 and Kawai KDP120, both brands have clearly spent time tuning their built-in speakers to complement their respective tonal profiles, but they’ve taken different routes to get there.

Casio PX-870 speaker setup

The PX-870 features a 2 × 20-watt speaker system, with each speaker measuring roughly 12 cm in diameter. The speakers are positioned to project sound both upward toward the player and outward into the room. Casio also incorporates an “open” back panel design, which allows some of the sound to escape to the rear, subtly enhancing depth.

The result is a surprisingly powerful output for a relatively slim cabinet. At medium to high volume, the PX-870 easily fills a small to medium-sized room without distortion. The tonal balance from the speakers tends toward clarity, with a crisp top end that helps bring out the brightness of the AiR Sound Source engine.

Bass response is respectable, though the PX-870’s low end doesn’t quite have the physical depth of systems that include a dedicated bass driver. Still, for most solo playing and general practice, it delivers enough warmth to keep the sound from feeling thin.

Kawai KDP120 speaker setup

The KDP120 also sports a 2 × 20-watt speaker system, but with a notable twist — it includes a bass reflex system that acts almost like a built-in subwoofer. This design allows the KDP120 to reproduce low frequencies more fully and with greater presence than many competitors in its price range.

The speakers are tuned to emphasize the warmth and fullness of Kawai’s Harmonic Imaging engine. This pairing works beautifully for solo playing, as the low end feels more rounded and supportive, and the mids are rich without being muddy. Even at lower volumes, you can feel a bit of that low-frequency presence in the room, which adds to the “acoustic” illusion.

The projection is primarily upward and outward, but the cabinet design helps the sound feel less directional than on the PX-870. It’s more of a “wash” that fills the room evenly, which is pleasant for listeners sitting off to the side.

Volume and headroom

In terms of raw volume, both pianos are in the same league. They can get loud enough for casual gatherings, small ensemble practice, or home recitals without needing external amplification. That said, the PX-870’s brightness can make it feel subjectively louder at the same volume setting, simply because the high frequencies cut through more.

The KDP120’s warmth and bass emphasis make it feel fuller rather than louder, which can be easier on the ears over long playing sessions. You won’t get the same sense of “bite” in the attack, but you’ll get a more enveloping sound.

Both systems hold their clarity well at higher volumes, with minimal distortion or speaker rattle — a good sign of quality amplification and speaker construction.

Stereo imaging and realism

Stereo imaging is another area where built-in speaker design makes a big difference. Casio’s PX-870 provides clear left-right separation, which is especially noticeable in pieces where melody and accompaniment are spread across the keyboard. The placement of the speakers in relation to the keys gives the impression that the sound is coming from where your hands are playing, which enhances realism.

The KDP120’s stereo image is a bit more diffuse, which contributes to that room-filling quality. It doesn’t give as sharp a sense of left-right separation as the Casio, but it does make the sound feel more like it’s coming from an acoustic piano’s soundboard, where notes naturally blend and interact.

Special features for speaker sound

Casio includes a “Hall Simulator” function in the PX-870, which adjusts the EQ and reverb to mimic different acoustic environments. Through the built-in speakers, this can make a noticeable difference, adding spaciousness and a touch of realism for certain repertoire. It’s not a substitute for playing in an actual hall, but it’s a nice way to vary the sonic atmosphere in a home setting.

Kawai focuses less on environment simulation and more on keeping the sound as natural and unprocessed as possible. There are still reverb settings to choose from, but the philosophy seems to be: “Give you a great piano sound, then let the speaker system present it faithfully.”

Listening position and experience

Because of the upward projection of both systems, the player’s seat is in the sweet spot for clarity and presence. The PX-870’s brighter character gives you a more immediate sound — it feels like the notes are right under your fingers, responding directly to your touch. This immediacy is motivating for energetic playing but can be a bit fatiguing if you prefer a more laid-back tone.

The KDP120’s presentation is softer and more enveloping, which can be comforting during long practice sessions. You feel less “in your face” sound and more of a surrounding atmosphere. This makes it easier to lose yourself in the music, though some players might miss the sharper definition in the upper registers.

External amplification considerations

If you plan to connect your piano to an external amp or PA system for larger performances, both instruments have line-out options. In this case, the built-in speakers become less critical, as they can be bypassed or used as personal monitors. Still, the built-in systems here are more than capable for any home-based playing and even some informal performances without extra gear.

Summary of strengths and trade-offs

• PX-870: Crisp, bright, and forward projection. Excellent stereo separation. Clear at all volumes. Bass is good but not as deep as the Kawai. Hall Simulator adds flexibility.
• KDP120: Warm, full, and enveloping. Stronger bass presence thanks to bass reflex design. Softer stereo imaging for a more blended acoustic feel. Less EQ shaping, more natural presentation.

The choice between them comes down to whether you want your sound to leap out with clarity (Casio) or wrap around you with warmth (Kawai). Both are strong performers, and in a blind test, you’d likely be impressed by either — but they will encourage slightly different playing moods and repertoire choices.

Features & Functions

While the feel of the keys and the quality of the sound are at the heart of a digital piano, the additional features and functions can transform it from a simple practice tool into a versatile music-making hub. These extras don’t just add convenience — they can change how you practice, compose, and perform. The Casio PX-870 and the Kawai KDP120 are both aimed at home players, but their approach to features reveals very different priorities.

Casio PX-870 feature set

Casio has long had a reputation for packing a surprising number of functions into their instruments, and the PX-870 is no exception.

One of its most useful features is the built-in song library of around 60 pieces. These range from classical standards to study pieces, and you can play along with either hand muted to practice left or right hand independently. This works in tandem with the built-in metronome, which is adjustable for tempo, time signature, and volume — an essential tool for consistent practice.

The PX-870’s “Concert Play” mode is another standout. It provides recordings of an orchestra or ensemble for you to play along with, using the piano as the solo instrument. This can be inspiring for learners who want to feel the energy of playing with other instruments, even without leaving the living room.

For customization, Casio includes functions like layer and split. Layer mode allows you to combine two voices — for instance, a grand piano with strings — so that both sound together across the whole keyboard. Split mode assigns different voices to the left and right halves of the keyboard, letting you, for example, play bass guitar with your left hand and electric piano with your right.

The PX-870 also includes a registration memory system, which allows you to save and recall your favorite settings (voice, split/layer configurations, effects) instantly. This is particularly useful if you often switch between different styles of playing or need quick changes during performance.

For recording, the PX-870 offers a 2-track MIDI recorder, letting you record left and right hands separately or layer multiple parts. You can also record audio directly as WAV files onto an SD card — a feature not found in many pianos at this price point. This makes it easy to share your performances without additional equipment.

One more modern touch: Bluetooth audio. This allows you to stream music from your phone or tablet through the PX-870’s speakers. While it doesn’t offer Bluetooth MIDI for wireless control, the audio streaming is a welcome convenience for playing along with backing tracks or simply enjoying music through a decent sound system.

Kawai KDP120 feature set

Kawai’s approach to features in the KDP120 is more restrained, focusing on functions that directly support piano practice rather than a broad palette of extras.

Its built-in song library is smaller in scope than Casio’s, offering around 50 pieces, many of them etudes and classical works from composers like Czerny, Burgmüller, and Beyer. The emphasis here is on pedagogical material, making it particularly useful for students working through graded repertoire.

The KDP120 has a lesson function that allows you to mute either hand and practice with the built-in metronome. It also integrates with Kawai’s PianoRemote app, which gives you more control over settings and lets you view sheet music for the lesson pieces. While the app-based control is slick and intuitive, some players may prefer having more direct control from the front panel without needing a mobile device.

Layer and split functions are present, though less prominently featured than on the PX-870. The KDP120 also allows for duet mode, splitting the keyboard into two identical pitch ranges so two players can sit side by side — ideal for teacher-student work.

Recording is limited to a single-track MIDI recorder. There’s no onboard audio recording to USB or SD card, so sharing performances requires recording via a connected computer or external device.

Kawai does not include Bluetooth audio or MIDI in the KDP120, which is a notable omission in 2025. All connectivity is wired, meaning you’ll need cables to connect to apps or backing tracks. The focus is on a stable, no-frills connection rather than wireless convenience.

The one standout in Kawai’s feature set is the “Virtual Technician Lite” function. While less comprehensive than the full version found on higher-end models, it still offers valuable tone customization. You can adjust voicing, damper resonance, key-off effect, and touch response to suit your playing style. This tailoring is subtle but can make the piano feel more “yours” once you dial it in.

Practical differences in use

In day-to-day playing, the PX-870’s wider feature set offers more flexibility. The registration memory and SD audio recording are especially useful for players who like to experiment with arrangements, create layered compositions, or share performances online. Bluetooth audio streaming is also a quality-of-life upgrade — being able to queue up a YouTube tutorial or a Spotify playlist and hear it directly through the piano’s speakers is a small joy.

The KDP120’s pared-back feature list means fewer distractions and a more “just sit down and play” experience. For some, this is a strength — no endless menus or setup routines, just the essentials for practicing and developing technique. The lesson function, combined with the onboard classical repertoire and duet mode, makes it an excellent partner for structured study.

Ease of navigation

The PX-870’s control panel is minimal but functional, with buttons for core functions and a simple labeling system. Some deeper settings require holding down buttons and pressing keys to access functions — not the most intuitive approach, but something you learn quickly with the manual.

The KDP120 uses a similar “button plus key” system, but with fewer functions to navigate, it’s easier to remember the shortcuts. The optional use of the PianoRemote app makes settings navigation much easier if you’re comfortable pairing it via USB.

Feature philosophy: quantity vs focus

The PX-870 leans toward quantity and flexibility — more sounds, more recording options, more customization, and more connectivity. It’s an instrument that tries to cover as many playing situations as possible, from solo practice to casual recording to light performance use.

The KDP120 leans toward focus and simplicity — fewer voices, fewer connectivity options, but a clean, streamlined playing environment. It’s designed for players who care less about variety and more about consistently high-quality piano practice.

Which approach works better?

If you like experimenting, recording, and mixing up your playing routine, the PX-870’s features will keep you engaged for years. It’s also a better fit if you want to use your digital piano as a central music hub, playing along with tracks, recording performances, and customizing your sound.

If you want a digital piano that acts like a disciplined, focused acoustic — no distractions, just a quality playing experience — the KDP120 is the better match. Its features are all in service of piano study, and the omission of extras is deliberate rather than an oversight.

The bottom line on functions

The PX-870 is the clear winner in sheer variety and technological convenience. The KDP120 wins in deliberate simplicity and focus on core practice tools. Neither approach is wrong — it simply depends on whether you want your piano to be a multi-tool or a specialist’s instrument.

Connectivity

Connectivity is the bridge between your digital piano and the rest of your music world. It dictates how easily you can integrate the instrument with computers, mobile devices, recording equipment, and even other musicians. While some players use their piano strictly as a standalone instrument, many modern pianists — from hobbyists to serious students — benefit from being able to connect to software, apps, and external speakers.

The Casio PX-870 and Kawai KDP120 take notably different approaches to connectivity. Casio leans into convenience and flexibility, while Kawai offers a more stripped-down, no-nonsense setup aimed at traditional piano use.

Casio PX-870 connectivity options

The PX-870 offers a relatively comprehensive set of ports and wireless capabilities for a home digital piano in this price range. On the rear panel, you’ll find:

• Two standard stereo headphone jacks (one 1/4-inch, one 1/8-inch mini-jack), allowing for silent practice by one or two players at once.
• USB Type B port for connecting directly to a computer. This allows MIDI communication with DAWs (Digital Audio Workstations) and music notation software without needing an extra MIDI interface.
• USB Type A port for connecting an external flash drive or SD card (depending on the market variant), mainly for playing audio files or saving recordings.
• Line Out jacks (stereo L/R) for connecting to external amplification or recording equipment.
• Bluetooth audio streaming (A2DP profile).

The inclusion of Bluetooth audio is a real convenience in everyday use. You can pair your phone or tablet and stream backing tracks, YouTube lessons, or music from Spotify directly through the PX-870’s speaker system. This is especially handy for playing along with recordings without needing a tangle of cables.

However, the PX-870 does not offer Bluetooth MIDI — meaning you can’t wirelessly send MIDI data to a computer or mobile device. If you want to use a piano-learning app like Flowkey or GarageBand, you’ll need to connect via USB.

The USB ports themselves are class-compliant, meaning the PX-870 should work with most devices without needing proprietary drivers. This makes it plug-and-play for Windows, macOS, iOS (via adapter), and many Android devices.

Kawai KDP120 connectivity options

The KDP120 takes a more traditional approach. Its rear panel includes:

• Two stereo headphone jacks (both 1/4-inch) for silent practice.
• USB Type B port for MIDI connection to a computer or mobile device.
• Stereo Line Out (L/R) for external speakers or amplification.

And that’s about it. There’s no USB Type A for flash drives, no audio recording to storage, and no built-in Bluetooth — not even Bluetooth audio. This keeps things simple but means fewer integrated conveniences for those who like streaming backing tracks or managing recordings without a computer.

That said, the KDP120 does gain a bit of extra versatility through app integration. When connected via USB, it can pair with Kawai’s PianoRemote and Virtual Technician apps on iOS or Android. These apps let you change sounds, adjust settings, and fine-tune the piano’s tone (in the Virtual Technician) from a touchscreen interface rather than relying on button/key combinations.

This is a cleaner and more visual way to manage settings, especially for beginners who might find key-combination controls intimidating. However, it’s still a wired experience, so you’ll need the right USB adapter for your tablet or phone.

Audio outputs and amplification flexibility

Both pianos have stereo Line Out jacks, which are crucial if you want to:

• Connect to a home stereo or powered speaker system for a fuller sound.
• Run the piano into a mixer for recording.
• Hook up to a PA system for a performance.

The PX-870’s Line Outs are particularly handy if you want to bypass the onboard speakers entirely — for instance, when recording in a studio where you want complete isolation.

The KDP120’s Line Outs serve the same purpose, but the warmer voicing of its Harmonic Imaging engine can sound particularly good through a high-quality speaker system. If you regularly perform in small venues, either piano could hold its own when amplified, but the Casio’s brighter tone might cut through more in a live mix.

MIDI and software integration

Both instruments send and receive MIDI data over USB, so they can double as high-quality MIDI controllers for virtual instruments and recording. This is important for composers and producers who want to blend the feel of a weighted action with the flexibility of software pianos like Pianoteq, Keyscape, or Garritan CFX.

The PX-870’s MIDI recorder is onboard, but it can also send MIDI to a DAW, letting you capture a performance for editing or orchestration. Likewise, the KDP120 can send MIDI directly to notation software like Sibelius or MuseScore, which is particularly useful for music students and arrangers.

While the PX-870’s extra USB port for storage adds some standalone functionality (recording without a computer), both will require a computer connection for advanced MIDI work.

Wireless options

Here’s a clear dividing line:

• PX-870: Bluetooth audio only. You can stream sound into the piano but not send MIDI data out wirelessly.
• KDP120: No built-in Bluetooth, but if wireless MIDI is essential, you can add it with a third-party adapter like the Yamaha UD-BT01 or Roland WM-1.

It’s worth noting that third-party solutions add cost and complexity. If you know you’ll want wireless connectivity for apps, the PX-870’s Bluetooth audio may partially meet that need — but you’ll still need a cable for MIDI.

Headphone outputs and silent practice

Both pianos cater to silent practice, but their headphone outputs differ slightly. The PX-870 has one full-size (1/4″) and one mini-jack (1/8″), making it easier to accommodate different headphone types without adapters. The KDP120 uses two full-size 1/4″ jacks, which is sturdier but may require an adapter for smaller headphone plugs.

Silent practice quality is excellent on both instruments, as each provides a dedicated headphone EQ that adjusts the tone to suit close listening. Casio calls this “Headphone Mode,” while Kawai uses a similar voicing tweak. The result is a less fatiguing sound that compensates for the lack of natural room resonance.

Integration with learning platforms

If you’re planning to use your digital piano with online courses or apps, connectivity matters more than you might think.

The PX-870 can easily connect to platforms like Flowkey, Simply Piano, or Playground Sessions via USB. While it lacks wireless MIDI, the stable wired connection ensures minimal latency. Bluetooth audio streaming also makes it simple to follow along with video-based lessons.

The KDP120 integrates well with Kawai’s own educational content through the PianoRemote app, but its lack of Bluetooth means that external learning platforms require a USB cable. For some, this isn’t a problem — wired connections are often more reliable — but for others, it may feel like a limitation compared to more modern wireless-enabled instruments.

Overall connectivity verdict

Casio PX-870 strengths:

• More versatile port selection.
• Bluetooth audio streaming.
• USB storage for audio recording/playback.
• Dual headphone jacks in two sizes.

Casio PX-870 limitations:

• No Bluetooth MIDI.
• Requires USB cable for app-based MIDI functions.

Kawai KDP120 strengths:

• Clean, straightforward wired connections.
• App integration for detailed control (PianoRemote, Virtual Technician).
• Quality headphone outputs and sound tailoring.

Kawai KDP120 limitations:

• No Bluetooth of any kind.
• No USB storage or onboard audio recording.

The decision here comes down to whether you value convenience and variety (Casio) or simplicity and focus (Kawai). The PX-870 gives you more built-in options, particularly for streaming audio and recording without extra gear. The KDP120 assumes you’ll handle most external integration through a computer, focusing instead on keeping the piano itself streamlined and distraction-free.

Conclusion

Choosing between the Casio PX-870 and the Kawai KDP120 isn’t about picking a “better” piano in absolute terms — it’s about deciding which approach to sound, feel, and features matches your needs and personality as a player.

The PX-870 stands out as a feature-rich, all-in-one home digital piano. It’s slim, stylish, and offers impressive connectivity, onboard recording, Bluetooth audio, and a bright, articulate tone that cuts through easily. Its action is solid and responsive, and the Hall Simulator plus other sound-shaping tools give you more flexibility to experiment. If you like having extra tech conveniences built right in, or you’re someone who wants to plug into learning apps, record without fuss, and occasionally stream backing tracks through your piano’s speakers, the PX-870 makes a strong case.

The KDP120, on the other hand, focuses on doing fewer things but doing them exceptionally well. Its RH Compact action has a more nuanced, acoustic-like feel, the Harmonic Imaging sound engine delivers a warm, natural tone, and the bass reflex speaker system creates a fuller low end than you’d expect at this price. It’s more of a “sit down and play” instrument — no frills, no distractions, just a very satisfying core piano experience. For players who value touch and tone above all else, or for those who want an instrument that feels more like an acoustic in daily play, the KDP120’s simplicity is part of its charm.

In the end, your decision should come down to priorities. If you want a highly capable, tech-friendly piano that delivers plenty of value for the price, the Casio PX-870 is a fantastic choice. If you prefer a purist’s digital piano that emphasizes authentic touch and tone, the Kawai KDP120 might well be your perfect match. Both deliver serious quality — the best choice is the one that inspires you to play more.