Use of RCA Y Splitters?

Yes, I was looking at the Audioquest M-22-F/FLX Y-Adapters which appear to do this.

Some other posts suggest that the best method is to use an active crossover which is probably the 100% solution, but wondered if the Y cable solution is "good enough" for most.

Please explain vertical and horizontal bi amping? What if the amps are NOT the same?

Thanks.

Thanks for all the input. Would there be an issue if the amps were not the same, i.e, not the same power output?

No, I was wondering about the effects of bi-amping with two different amps.

Yes, the equivalent impedance as seen by the pre-amp output would be reduced.