Can I use XLR to connect pre-amp to amp and RCA to connect pre-amp to sub?


I'm hoping someone can help me out. I'm contemplating getting a preamp that has XLR outs so that I can connect my preamp to my amp using XLR (balanced connection). Would it be possible to use RCA (unbalanced) out to connect my sub, a Vandersteen V2W, while at the same time connecting my pre-amp to amp using XLR?

I've searched and can't get a definitive answer as to whether this would be ok, or do something weird. From what I gather it would be really bad to use both RCA and XLR outs for the same connection. 
thanks for your help
128x128mzwerner
Yes. No problem. As long as both the xlr and rca outputs can be driven at the same time from your pre.
What preamp?
Where you connect the external high-pass filter to? Is your preamp has a tape loop?