Connecting two power amps to Preamp

No problem at all ..
but if the gain of the power amps are different each will output a different wattage for the same signal.
hence if you are Bi amping horizondally, the input into the tweeter and the woofers will be different and if you are vertically bi amping then one speaker will have a different output than the other..

to do this well you need to have an attenuator in the P-amp with the higher gain and try to match the levels.. but its painful !

ckn schrieb:

Hi, Question for the knowledgable. Can i connect two power amps of different w.p.c. to the same pre amp?

yes! no problem if the output imp of the preamp is small enough (50 ohms, 600Ohms, 1KOhms) & the input imp of the power amp is large enough (50Kohms, 100Kohms or higher).
If this is not the case, what will happen is that the preamp will load the power amp & you'll get rolled off high freq + the bass will sound bloated.

ckn schrieb:

Are there any specific things that one should watch out for?

see above re. inp & out impedances

ckn schrieb:

Will combining tube power amps to a SS pre amp pose any problem? Thanks in advance. ckn

should not if you ensure that the inp & out impedances are low enough & high enough respectively.

Also, read "Arj" comment re. the amps having diff gain hence having diff output levels for the same preamp volume setting. Additionally, the tube & SS power amps will have diff sonic signatures that might or might not blend w/ each other - particularly important if you are bi-amping.
if you have 1 amp driving 1 pair of speakers in 1 room & the other amp driving a 2nd set of speakers in another room, tonal signature should not be an issue.