Of course it depends on your budget. You'll find that some players do prefer practicing through headphones, but probably most prefer a small (practice) amp, like the smaller Fender rumble combo amps. The reason for this is to be able to get a sound similar to what they would get at a performance (gig). It's more than just playing the notes, which , in a quiet environment, can be heard with no amplification. Also, a practice amp with a 10 or 12 inch speaker is large enough to be used for small, low volume acoustic gigs (electric bass with acoustic guitars, banjos, fiddles, etc.) in smaller venues (coffee houses, restaurants, etc.). If you can't really afford one of those, consider using the headphones for a few months while you save up for one of the larger practice amps ($200 - $400). This will also give you time to become more knowledgable about your needs. Since you are a pianist, you know how important the quality of the instrument is for tone. For electric bass, the amplifier is a critical part of the instrument. If you buy cheap, you'll end up buying twice. Let your ears decide which amp to buy. BTW, welcome to Talkbass and to bass playing!