If you're referring to the Yamaha silent violin, then this applies. I have played it before and find the sound to be very quiet without phones on; this is logical because it lacks an acoustic resonating body. However, the yamaha silent violin is heavy, and has a very low quality tone even with headphones on.
There are other makers of electric violins if you'd like to find an instrument to practice on at lower volumes, but as others have said, if you are playing on (1) an instrument other than your main one, at (2) lower volumes, you'll have the wrong sensation of harmonics, the wrong sensation of shifting, and just generally will have to adjust to your regular instrument. They are a good idea in concept but haven't been perfected yet. It's still better to just play with your regular instrument.
If you're talking about electric violins in live peformance it's a whole different story; it's best to mic your favorite instrument with a high quality mic and use the best acoustic amp you can find, unless you're getting dirty with distortion, then it really doesn't matter because the amp's tone will dominate over the instrument's normal tone, and you can use a variety of hybrid or pure electric instruments. The ones with barbara pickups are the best in my rather limited experience with electric instruments. If it costs under $1,500 it will probably sound bad, like the electric I own.
Cheers,
Geek