Why am I struggling to make bass sound good through PA?

[mrtcat]

We have a great PA (rcf 932a x2 and rcf 905 sub x2) and a capable mixer (XR18) and yet im never happy with the bass sound through PA. 

 

I have a Darkglass Anagram which sounds amazing for recording direct into a PC and awesome on the multi track live recording we take direct from the desk at gigs. It also sounds perfect in my iem mix. My amp is a Darkglasd M900 and my cab is a greenboy F112. That setup sounds killer too.

 

Why is it then that the bass sound coming out of the PA just always seems to sound a bit woolly and soft and lacking those lovely clean piano type lows. Even if I turn all processing off on the desk it seems to sound like it lacks the clean weight of sound and crisp top end. Do I just need to be braver with the eq or is it something in the PA speakers that hates me?

[Bill Fitzmaurice]

PA subs go as much as an octave lower than bass cabs, while PA mains don't have the rising midrange typical of bass cabs. Try high passing the desk bass channel at 60 to 80Hz, if it has that capability, or cutting back on the bass EQ if it doesn't, while boosting the mids in the 2 to 2.5kHz range. 

 

If you want to be more precise get this app for your phone. https://play.google.com/store/apps/details?id=com.dom.audioanalyzer&hl=en_US&pli=1

You can use it to see the frequency response of your rig. Play an open A and take a picture of the result, C weighting, slow response. Save it and compare it to the same test through the PA. Comparing the two will show where the PA EQ needs to be adjusted. 

Edited 1 hour ago by Bill Fitzmaurice