I have find an easy way to correct this FRFR celestion speaker. we need to calibrate it with our eviroment.
because there is variable of Room, speaker placement, power amplifier coloration etc.
So i had use the global EQ settings in the AXE FX III. to correct this frequency response.
Get preset from leon tod preset, that to find speaker resonance. but change the sine wave to pink noise.
Using KRK audio tools. and then adjust the global EQ to flat as you can. with the help that brownish line (peak indicator).
to verify it, tell the apps to make eq recommendation. if you succeded it will tell you to set it to "FLAT EQ".
Now my speaker is sound so good.
can do marshall sound, and fender sound like heaven in that JTM 45 blues lead preset.
I'm very happy now because this is the most economical FRFR solution available to me. i dont need to make any cabinet, just direct replacement.
it is sound very similiar to my v30 because i play it a lot.
And btw, I burn in my new speaker by playing song from itunes via axe FX for some hours did reduce the harshness of this speaker.