Bi - Amping

I'm not sure what you mean in this case.

You want to mix amps in a home theater?  That's fine.

If  you want to mix amps that go to 1 speaker, so long as you have separate inputs and level controls on the amp, easy.

@georgehifi 
my preamp is Michi P5 
I can run Two amplifier at the same time one on balance XLR and other RCA 
I was thinking anthem for LF harman Kardon for HF ?

@erik_squires 
no for two channel listen 
im using Michi P5 preamplifier 

http://www.rotel.com/sites/default/files/product/manuals/p5_om_en.pdf

Preamp Output w
See Figure 3
The P5 RCA-type output connectors are compatible with most power control amplifiers. As always, select high quality audio interconnect cables. Connect the left and right channel outputs of the P5 to the corresponding inputs on the amplifier or other component.

NOTE: There are two sets of RCA outputs on the P5. The second set of outputs may be used in custom system configurations to drive a second power amplifier or to supply a signal to a special signal processor.
Balanced (XLR) Output e
See Figure 4
Two pairs of XLR balanced connectors supply an analog output signal from the P5 to a power amplifier with XLR balanced input connectors.

NOTE: Do not connect both the RCA and XLR to the same control amplifier at the same time.

@georgehifi
my preamp is Michi P5
I can run Two amplifier at the same time one on balance XLR and other RCA
I was thinking anthem for LF harman Kardon for HF ?

That’s fine so you won’t need "Y" connectors.But unless you have individual level "set controls" for both outputs and a master on that pre to then raise them both up and down together, your going to need a Sys passive on the louder of the two amps as per my diagram so you can equalize the gains.. https://ibb.co/QpmW5mh

Cheers George