I don't have an 881, but had a 771 for a while. Speaking in general terms about Sansui receivers from the single digit series through the x0x0 series, I don't think you'll hear a big difference. You can see my Sansui gear in my signature below. I have to say that comparing the sound of them (run flat, no tone control) there are some noticeable differences, but it is subtle AND depends on the type of music I'm playing. One type will sound better on one system, and another on a different one. Before you spend the money on another receiver, I'd recommend getting a good equalizer and playing around with the controls to see if a different tone curve makes the music you like to listen to on your 881 sound better. As we all know, the room acoustics and speakers make a significant difference, so it's really impossible to say whether an Eight or 8D will sound better in your application. But I would say, if you can't create a better sound with an equalizer, it's unlikely a different receiver will sound better to you in your environment, with your speakers. The 881 is a quality, TOTL receiver.