Dave Rat - IM distortion in monitor wedges

http://www.ratsound.com IM distortion is an artifact caused by the interaction of multiple signals. Introducing a low frequency tone while speaking into a monitor wedge causes the sound to blur a bit. Put the tone into a separate wedge and the the voice remains clear.

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[hacksawowner]

I can see where Dave is correct in saying that "subs on aux" does not directly address the problem since you still must put kick and bass in the mains to retain the upper sonics. That said, wouldn't today's modern high-order electronic crossovers eliminate (mostly) the problem? In other words: subs on aux + 24 db/oct. hi-pass on mains. And just for lagniappe (cause i'm from Louisiana) what effect does IM dist. have on full-range drivers like those with wizzer cones since they are phase-linear?

[www73171]

@hacksawowner The audibility of IM distortion issue tends to be related mostly to cone motion. As a general rule of thumb, "Any speaker reproducing high frequencies that also moves significantly in order to reproduce low frequencies will tend to modulate those higher frequencies creating a sonic burring effect."

[hacksawowner]

What are the drawbacks of running a dedicated vocal PA versus the typical single PA, and wouldn't running "subs on aux" alleviate most of the IM dist. problem in a standard system?

[www73171]

@hacksawowner The drawbacks are cost, size, added complexity and potential issues with coverage differentials between the two systems. Sonically a well setup dual PA will outperform a single system

Subs on an aux do not directly address IM distortion but does reduce rumble in the subs from mics that you do not want subs on.

[SuperHotLarry]

Where is this facility??!?! it look super cool

[www73171]

@SuperHotLarry That would be the Rat Sound shop.

[plsr80]

@hacksawowner I've actually been thinking about that same exact idea here lately just because of the different frequencies of vocals/bass/guitars etc. Good to know I'm not the only genius out there! =)

[www73171]

@Paitsch there are significant differences between wedge and in-ear monitoring. In-ear tend to isolate the band members from both each other and the audience.

Also, the sound an artist hears with in ears is the same regardless stage position. Wedges you can walk to different areas and alter what you hear. Both are useful but different, some artists prefer one more than the other.

Also in-ears suffer from IM distortion as well, hence the reason u see multi driver in ears coming out.

[Paitsch]

Couldn't you just use in ears?

[1956pepper]

blinded me with science!