I have been fighting a low ferquency hum in my mic using a keyboard stand mic boom. The speakers on my pa1000 are so strong that when playing loud without external speakers for super small jobs I would get a low frequency hum aka low feedback from my mic.I can almost eq it out but it looses the sound I like to have and I love to run my mic super hot so I can sing soft then back off on the loud parts. I just bought the shure ASSM shock stopper mic clip from amazon and put in on my boom. It's a little snug with my samson Q7 but it fits better with my samson r11 that I like a lot. WELL ALL LOW HUM IS GONE!!! And that is with my regular eq settings. Best $20.00 I ever spent. you can even pat the boom and nothings gets heard over the mic. I can't recommend this holder enough
MEL

I don't find that model number. I use one, but not that one.
The R11 has a LOT of low end e.q. When I use one, I have to really roll off the bottom. Love the Q7 and the Q8 even more.
Also, you could experiment with the compressor to even out the vocals.

Is there a low cut filter on pa1000 mic ??

I use both the compressor and tried to eq the low end. Of coarse if I turn off the internal speakers, no problem. now I can leave the speakers on so I don't need a pa on livingroom gigs.
MEL

Sorry guys the model number on the mic holder is SHURE A55M
MEL