I have 2 of these amp kits and want one for a subwoofer and the other for 2 speakers. I was wondering if there is any way to get both channels of the one amp to power the subwoofer for more power. Thanks. 
It looks like you can, according to the datasheet - check out page 8 here https://www.sparkfun.com/datasheets/Com … STA540.pdf for bridging diagrams/ratings
Hope this helps!
Would that give me about 70W of power then? I see that you can bridge them on the pin outs, but how would it be done with the spark fun kit? It has 2 channels out. Thanks
We’ve not tried bridging the kits together but if you can match the outputs of both, it would probably work OK. You don’t want one kit trying to drive the other though so keeping them in balance would be critical. The left, right, ground and standby pins that are behind the heatsink would be a good place to bridge the inputs together, then you would only feed audio in through one of the boards to drive them both at the same level.
Make sure you have 40+ watts of power available for each boards. (80-100 watts total for both)
Can’t say for sure if this is going to work just be aware of the possibility you could blow both boards out if they somehow get out of sync with one another. Fuses on the speaker outputs would be a good idea while you’re testing and fuses on the power inputs would be strongly recommended.
Thank you. I didn’t mean bridge the 2 kits together, I meant bridge the 2 outputs of one of the amps together.
I think that would work too, connect the left and right channels together on the 6 pin header and I think you should be able to bridge the outputs. You might want to just feed audio in through one input channel though.