It's a hard thing, at least to me, to compare speakers when you have to disconnect one pair, turn the tube amps off, change speakers, then turn amps back on and wait for the tubes to restablize before listening. It just makes it impossible to do an AB test with your short term memory in tact. So instead, I have been listening to each set of speakers for days on just enjoying them. To be fair I have been listening to the AV/SP1s augmented with 2 Largersubs lowpassed at 50 Hz.
I like the Bella speakers. From the get go, they were very clean to the point of being lean. Initially, I couldn't listen to Judy Collins because she was just too monotonous and single pitched to the point of annoyance even with 6SN7 preamp and KT 88 tube amps with 6SN drivers in the chain. I also used Iliana Cortrubas, Annie Haslam and Maria Callas (vinyl only for her since she is unlistenable on CD) for my test listening. They have difficult voices to reproduce nicely, but Bellas have now filled out and reproduce them quite nicely. I would characterize these speakers as neutral and accurate but with some extra mojo that makes them special.
I don't know much about the acoustics of flutes, but I tell you that these speakers do open air pipes and flutes in a glorious way. From flutes, panpipes to Shakuhachi, the Bella SP/AV1s resonate harmonics of these open air pipe instruments like no other I have heard. A poignant passage invokes that pang in your heart to a point of ache like an unrequited love you felt as a teenager. I have never heard them like this before. In the same way the vocal texture of female singers are presented with pleasingly warm timbre. The notes are still clean and accurate, but now the vibratos and harmonics of the voices are blended in a evocative way. Turn the lights off and the glows of the tubes and the airy voices transport you into the heart of music. Just what I want for a bedroom set. The micro dynamics of these speakers are exceptional.
