The house gets few visitors. So it was rather fun last night to host a very brief choir rehearsal. For a little while the Keeping Room sprang into life. The old ghosts of the many formal and impromptu concerts given around the grand piano were there, whether it was in Chopin or in the Whiffenpoof songs of Yale. Outside, the lush green of summer rises, and inside, the golden room echoes with voices and laughter. The Keeping Room is large, ample space for a Steinway and eight people to stand and sing in the north bay, leaving the rest of the room open for the audience. Rather good acoustics too.