Just get an amp with a headphone jack, probably modelling or solid state. Or get an Amplitube system and play through the computer. It's the only real solution. I bought a Fender Champion 20 and a good set of AudioTechnica headphones for this purpose. I used the "65 Deluxe" patch for a clean platform, then ran my regular pedalboard into the amp and it sounded fine. Even a 1W tube amp through a 6" speaker sounds "loud" to family trying to sleep in the next room.