Strange Tweeter Impulse??

[Robbie010]

Morning all,

I'm just having a play around with time and phase alignment in my active setup with DIY 3 way speakers. I've independently measured each driver using an acoustic time reference and I get a strange impulse response on my tweeter which seems to have an early impulse at -1.0ms before the main impulse just before 0ms:

What am I seeing here, is this a reflection due to the mic being too far from the source?

 

[Sokel]

How do you use the acoustic reference?
Same speaker, other speaker, other source, how?

Is mic and DAC at the same clock?

Edit: DSP filters, I presume, linear ones?