What is your opinion of single driver speakers

I have not heard the Sibelius but I did own a few single driver speakers, mainly using Lowther drivers. I think Bache's design of using a modified single driver to cover the range from 500 - 8,000hz, augmented by a super tweeter and woofers is a better way. The crossover is a cap for the tweeter and a coil for the woofers. The midrange has directly connected to the amps.  It's more balanced than when I was using a Rel subwoofer with a pair of Rethms.

Single driver speakers can sound amazing.  For example filed coils to me are exceptional. Matching to the right amp also helps.  845, 45, tubes amps and some 1 watt amps make such speakers sound amazing.  Uping the price the horning speakers are also a consideration if you got the scratch.

Happy Listening.

What are you thinking of driving the Pearls with?

I am not familiar with PA but have used the Audience 1+1 for years. Single driver speakers eliminate one of the most vexing problem that designers encounter when putting a system together: the crossover network. Passive network are almost impossible to get right on a budget. Without the crossover and with the right driver, the midrange purity can be addicting in a single driver system. But like everything else in life, you can’t get it all.  The bass might need help depending on your music preference. Your might need to add subs if you want it all. 

some are top notch, some are good, and i imagine some are no good. theyre as good as you wish to purchase. lotta folks buy tannoy cox and never buy another speaker. ive got a really good pair of halford margaritas (halfordloudspeakers.com) using some small fostex drivers. 

i dont know pearl acoustics