Bi wiring?

Since the power ratings are so different, you'll need to balance them out.

Since the voltage sensitivities are probably different, you will need to find a way to balance them. Power output capacity is irrelevant.

BTW, if the 300wpc amp is a good one, it will do just fine alone and without biamping. You do not need to have an amplifier capacity equal to the speaker's maximum rating.

Kal

use the amp that sounds the best imo

do not bother to biamp unless they sound very similar

if they are similar use the 300 watter on the bass

it remains to be seen if the sensitivity (I think the right word) of the amps is similar which would determine volume and compatability

have fun and be careful not to blow anything...

First, if you are using the preamp section of the receiver you can't bi-amp unless the receiver provides output jacks from its preamp section. Otherwise you would have no means of providing inputs to the separate power amp that are controlled by the receiver's volume control.

Second, bi-amping (or at least passive bi-amping) is unlikely to provide a significant increase in overall power delivery to the speakers. See the posts by me and by ElDartford in this thread. If done properly, with matching amps, bi-amping can provide some sonic benefits, but as was stated above that is not likely to occur using a receiver in combination with a dedicated power amp.

Third, I think that everyone is (correctly) saying the same thing about balancing the outputs of the two amps, but I would put it that what has to be matched are the voltage gains between the outputs of each amp and whatever point earlier in the signal path is common to both amps.

In other words, if you were connecting the preamp out jacks of the receiver (assuming it has them) to the power amp input jacks of the receiver and to the external amp, you would need to somehow match the gain of the external amp to the gain of the power amp section of the receiver. If you were connecting an external preamp to the external power amp and into input jacks of the receiver, you would have to match the power amp gain with the gain from those receiver input jacks to the outputs of the power amp section of the receiver. You could probably do that with the receiver's volume control, at the expense of the sonic effects of having the receiver's preamp section in the signal path in addition to the external preamp.

The gains can be calculated by taking the rated power output of each amp into 8 ohms; converting to voltage using the equation E = Square root of (P x R) (where P = rated max power into 8 ohms in watts, E = voltage in volts, and R = 8 ohms); and dividing by the input voltage that is specified to produce that rated output (the "sensitivity," as was stated). The resulting gain can be converted to db using the formula 20log(Vout/Vin).

Regards,
-- Al

YOU MUST ADD a crossover to feed the right stuff to each half of your speaker.

No. You must REPLACE the inbuilt crossover with the proper custom external one if you want proper biamping. This means that you must REMOVE the inbuilt on in the speakers in order to avoid cascading the two.

OTOH, you can leave the inbuilt one in place and not INSERT an external one but this will minimize any advantages of bi-amping.

You cannot use BOTH crossovers.

Kal