With the Yamaha exclusive Intelligent Acoustic Control (IAC) feature, the digital piano can be played at a lower volume in a quiet environment. The instrument adjusts the balance between bass and treble automatically, creating more depth to the sound. Additionally, the volume dial will automatically make fine adjustments to the overall speaker system (EQ) when playing at a low volume ensuring the highest sound quality regardless of the volumeInteraction USB cable can be used to connect the instrument to a PC or mobile devices. The Digital Piano Controller app has an interface that is optimized for iOS touch screens, adding functionality to this digital piano.The inclusion of Bluetooth connectivity is a plus.The internal recorder allows you to record one 2-track song, however, there is an addition of an external recording device, which is a big bonus.Pros • Comes with Graded Hammer synthetic ivory keys.• It has a192-note polyphony.• Has superior key action with three key sensors.• The inclusion of Bluetooth connectivity.• Comes with a recording and playback feature.• This piano does not need to be tuned.• Saves energy with the auto power off.• It has the Yamaha Pure CF sound engine.Cons • Does not have a screen display.• It is not portable.Kurzweil ARTIS 88-Key Stage Digital PianoThe Kurzweil Artis 88-key stage piano is designed to be simple but powerful. This piano has taken performing to a new level with its captivating piano sound, dependability, and ease of use.The Artis features a completely new German 9′ grand piano sound as well as 225 other stage sounds. Comes with a 128-note polyphony, Hammer weighted key action and with the impressive FX engine, you can easily fine-tune your sounds through the nine sliders and a dedicated 3-band EQ section.88-Hammer Weighted KeysThe Kurzweil Artis’ 88 hammer weighted keys are smooth and faster like those of a real piano. In addition to that, the keys have an added advantage of velocity and sensitivity which means they respond to how fast the hammers strike the strings from the key press speed giving your playing the perfect volume and tone.Amazing sound With Kurzweil Artis, the sound is rich and full and there are 256 preset factory programs. These preset programs feature some of the best Kurzweil sounds including the Kurzweil PC3 and KORE 64 ROM expansion. Other included sounds are strings, synth sounds, drums, horns, and many more128-note polyphonyHaving amazing 128-voice polyphony, the Kurzweil Artis gives you all the support you need when playing even the very complex of sounds without dropping any notes on maximum polyphony. Additionally, it has a feature for selecting which voices to drop in favor of new ones. This will result in seamless and natural performances even when you play heavily layered sounds with many effects.User-friendly interfaceThe Kurzweil Artis digital stage piano has an extremely user-friendly interface particularly handy when performing on stage.It features nine drawbar sliders and five assignable performance control switches that enable you real-time fine-tune of the piano sounds. In addition, with the quick layer/split control, combining and layering sounds easy and fast. You also get a 1-button recall of your most-used Programs and Multis.Interaction The piano has two footswitch jacks that can take either double pedals or single conventional, TRS pedals that support half-damper action. Another separate jack is the continuous control pedal.USB jacks are also provided for both computer and smartphone connectivity or any thumb drive for storage of data. The 1/8″ stereo input is for linking music playback devices to the outputs and there is also a headphone jack around the front.Pros • The piano is easy to use and to set up.• It comes with USB connectivity and flash drives.• Features a powerful FX Engine that offers multiple effects chains.• Has a user-friendly interface.• Provides 128-note polyphony.Cons • It has no onboard drum patterns.• You can record or playback audio files through the external flash drive.• No access to primary programs when split layering is engaged.• Only ten Favorites are available.