Altec 511B horn compared to the GPA MR931

[RonSSS]

I did some measurements tonight, since my test rig happens to be set up right now.

I took a 902 and measured from 1 meter, on-axis. Comparisons of MR931, 811, and 511.

The reason for the lower response from 0 to 120Hz on the 511 is the attic fan turned off (which was running during the other two tests and contributes some LF rumble).
If I am feeling motivated this evening, I'll take some off-axis measurements...

Why would you measure below 300hz? Seems like it would be easy to damage them.
Can you detail your test setup for us?
And, because I'm lazy, what is the MR931? The little guy used on the model 14?
Edit: I went and looked...I never did like those.
I have a pair of MR994 that I like quite well but have never really built into a system for critical evaluation. Small format 500hz, they are huge!

Ron