power division question

[Pandafist]

If I combine a 4ohm 4x10 and an 8ohm 1x12, how is the power divided amongst the cabs?

Here's my situation.
I have a 4x10 (4ohm) that I run through a GK RB800. It has jacks in the back for 4 and 8 ohms.
If I added an 8ohm 1x12, I'd run that cab from the 8 jack, and the 410 from the four ohm jack? Or should I run them both from the two 4ohm jacks because it's closer to a 2ohm load?

My reason for asking is this. I'd like to add the twelve for tone, but I don't want to steal too much power/volume from the 410.
Should I get the 4ohm or 8ohm 112 (Avatar)?

 

[Revmizery]

You should read the user book for the head. They are separate power amps, the high amp will give you 100 Watts at 8ohms and the lower will give you the 300 watts at 4ohms. you can not mix the the speaker independence's as it no where states that you amp will run at 2 ohms. this will most likely damage your amp.

 

[IvanMike]

well i would normally say check the ohms faq in the amps faq sticky but the gk 800 is a wierd amp. the 800 was designed during the bi-amp craze. i don't remember if you can run both of the amps in it full range or not. the 300 watt 4 ohm stable amp is usually used full range but also gets the lows when the crossover is engaged. the 100? watt 8 ohm stabel amp runs the highs when the crossover is used, and i'm not sure if it will run full range with the crossover off.

that said, you can't use another cabinet of any impedance in the 4 ohm stable amp because you're already using a 4 ohm cab (the 410) in that amp. (there are actually two seperate power amps in the 800rb).

you are really limited to using an 8 ohm cab in the 8 ohm stable 100 watt? amp beacuse that's all it can take. with both of those power amps (like all SS power amps) running an impedance lower than the stated minimum will cause the amp to overheat and fail (break).

hopefully someone will know if the 100 watt 8 ohm section can be used full range. than you can use whatever 8 ohm cab you want in it.

 

[Revmizery]

I am reading the manual for the 800RB and they seem to be two separate power amps when the Bi-amp not in use.

 

[Band Dad]

My son uses this setup, and it should work well for you. Yes, two separate amps that can be run bi-amped, allowing you to use the crossover, or full-range. When run full range you're getting the entire signal sent to both amps, relying on the cabs to utilize the signal to the best of their abilities.
This was recommended (full-range) by a number of TBers that are familiar with the 800RB, and it works great.

Edit: They are two separate amps regardless of whether you use the bi-amp feature, or not.

 

[Blues Bass 2]

Like Band Dad says they are separate amps and both can be run full range. Use the 300 watt amp for the 410 and the 100 watt for the 112,should work fine.