pass XA 60.5 vs Pass X250.5

What is the brand and model of your speakers. Practically all mid-size and many full-size speakers can be driven by the XA60.5 alone. Each of the XA60.5s has 2 sets of output. You can separately drive the mid/high frequency driver using one and the low frequency driver with the other output. Basically you might not need the XA30.5 on top of this at all.

I suggest you call Pass Labs and ask them the same question. The thing is upper and mid frequency drivers don't take much power. It's the bass driver that wants a lot of juice. They might tell to do away with your XA30.5, but then they might not. As to the bass driver, I tend to agree with Tvad. However matching the timing and everything else between the higher and lower frequency signal might be an issue. Just call Pass. Since you already invest in the XA30.5, you might have to stay with Pass for the driving the woofer, say the X250.5 as several people have favored.

On the flip side, the combine cost between XA30.5 and X250.5 is about the same as XA60.5. So if Tvad is correct, you might want to sell your XA30.5 and just purchase the XA60.5 only for now. I did look at Siegfried Linkwitz website, and the suggested power for Orion woofer is only 60 w/channel. That is a very small demand for a woofer. What I'm get at is that your woofer is an easy one, despite the 8-ohm impedance and a good to excellent sensitivity of 84.8 dB.