Off-Axis Live Tone Phenomenon: Insight/Solutions?

Well, someone’s going to say it, so I’ll be the first. If you have full PA support, your stage rig basically becomes a personal monitor. Best advice is to get the speaker tilted up and aimed at your ears.

Regards,
Wayne A. Pflughaupt

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six more speakers.

 

The fact that HF sound and the HF driver are more directional could be the cause? EQ for position in front of the cab as a possible solution.

 

Cone drivers become directional as frequency increases.

These image polar plots are for a 15" driver:


Here is the text that explains the images:

Off axis cancellation effects are often illustrated through polar response graphs which show the dB level at various angles from 0 to 90 degrees. In the diagram the dimensionless number ka refers to circumference* divided by wavelength. *circumference can be easily calculated as pi or 3.141 multiplied by the diameter.
For example a 15″ piston has a circumference of around 4ft, so ka is around 250Hz. Above ka = 1 the piston starts to become directional. Relatively smooth off axis response is maintained to ka = 2 (500Hz for the 15″ piston) but by ka = 5 (1250Hz for the 15″) the piston is beaming with notable response lobing.
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A 10' driver would develop similar dispersion patterns, although at a higher frequency.


The interaction between two drivers also has an impact. If you have the speaker oriented horizontal, it actually narrows horizontal dispersion. Likewise if you orient the drivers vertically, the vertical dispersion is narrowed.

I suggest aligning the drivers vertically and aiming it at your heard. Then adjust the amp to taste.

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One possible solution is to stand in front of your cab and change your EQ settings (decrease highs)...

 

Neither your on-axis nor your off-axis cab sounds will sound the same as the di, but I bet you the on-axis is closer.

 

On an outside gig, even with PA support, there are no walls and no coupling to help "beef up" your stage rig. A 2x12 can sound thin outdoors from the player's perspective simply because all of the actual low end is likely blowing right past you and more prominent about 20 feet out front.

 

IIRC, the 212AV speakers are on a diagonal, possibly the worst overall configuration for this sort of filtering. Try to tilt it up next time and stay in the front cone. If the sound there is too harsh, thats the sound the house is hearing. Fix it