Questioncan a speaker hum be created if the amps can put out more power than the speaker can handle. it also is a 4 ohm amp and the speakers are 8 ohm. so i put two speakers on the left channel and the right to create 4 ohm for each should this not work.
AnswerONE: Power rating differences cannot cause hum.
TWO: Impedance of load is no problem when higher than the amp rating. Danger exists only when the load impedance is less than the load rating of the amp.
THREE: Paralleling two 8 ohm speakers will provide a load of 4 ohms. No problem, but not necessary - unless that is what you want to do.
FOUR: Hum is coming out of the amplifier. You must determine where it is coming from; internal to the amp, bad grounds from the input, etc.
FIVE: Here is a good test: Turn the volume to zero and listen for hum. If the hum is not present with volume down it means the hum is coming from either within the front end circuitry or, more likely, from a bad ground or something wrong with the input source. If the hum is audible all the time it is a problem with the ripple filters in the power supply circuit of your amplifier - or something like that; it requires further investigation and service.
SIX: Hum resolution is usually either very simple and easy to fix or very illusive and mysteriously difficult to track down; nothing in the middle. Let me know which case you have and, if you don't solve it with this first note, let me know and we can go further into it.
Hope this helps.
C
