Just started reading this thread after I did some measurements of some of my wedges today 
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I'm interested in if the phase response shown here is a result of incorrect measurements taken or if they are "ok" for what they are.
3 speakers were measured.
EV SxA250
Peavey PV 15pm
Yamaha MS400
Not a lot of filters were needed to keep them in a +/- 3db range.
Looking at them the Yamaha looks like the horn is not in correct polarity to the woofer but there is no major drop in response at the crossover point. There was an acoustic adjustment device used to raise the front up so I wonder if that is part of the dips in phase and response in the woofer range?
The peavey phase seems to be about what I'd expect to see.
The EV I'm unsure of as to if this is normal for this speaker?
Both the Peavey and EV have a peak around 200hz. I took this to floor / mic placement issue although I didn't see it in coh.
Coh was fine for this measurement and I was in a good sized room. I used the setup like in the Mic/speaker picture.
Thanks for any input on these. Sorry for the cell phone pictures..
Douglas R. Allen
Douglas,
There really are no "incorrect measurements", but interpretation of measurements can be difficult.
The proximity of the monitor's baffle to the floor will affect FR and phase response somewhat, "audio logs" , "acoustic adjustment devices" or Angular Discrepancy Adjustment Modules (ADAM) all will get the HF pointing towards your ears, but change response due to differences in diffraction and woofer wrap/bounce.
The PV 15pm has the least phase wrap of the three monitors you tested, about 130 degree from 250 Hz up, the Yamaha MS 400 a bit more at around 145 degree, the EV the most at around 270 degrees.
Considering they all use active electronics, none of the phase responses look great, but none look "incorrect".
Below is a screen shot of three speakers with flatter phase response, a Mackie 1502HD, an active 2 way using Gunness focusing, and a DSL SH100, a passive 8" coaxial two way, and a Welter Systems 8H, a passive 8"& horn floor monitor.
The 1502HD and the SH100 were measured on a 6 foot pole, the WS8H, measured as in your picture.
I'd bet if you took another set of measurements with the PV, Yamaha & EV you could not reproduce the phase charts. Each of these monitors is designed with the HF horn placed horizontally adjacent to the LF driver and will have a different response depending on what is chosen as "on axis", and the response off axis to the left will be different than to the right.
The 1502HD, SH100 and WS8H are all quite consistent in response from left to right.
The Yamaha MS 400 manual claims a 30 dB per octave crossover at 1600 Hz, the phase looks consistent in that range, what makes you think the "horn" is not in correct polarity to the woofer?
Art
