Taking measurements without proper gear

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Hey, so I'm doing my first two-way build using SB Scoustics SB17MFC35-8 and the Vifa XT25SC90-4. I've done a couple sub the past so I'm all good on cab design. I'm also relatively confident in my ability to design a x-over although I'm sure I still have a lot to learn.

So hears the issue, I don't have an Omni mic. Now this is just a project for a mate so he can DJ in his bedroom for fun so it's doesn't have to be perfect. So I had the idea of using my AT2020 to record the frequency response of the drivers when they're in the cab so I can design an x-over and then just try and match the response in xsim to that of the AT2020's response graph. I realise this will hurt a lot of people and everyone is just going to say buy the proper gear, but that's not an option right now, so do you guys think that my idea will allow me to produce an acceptable crossover?

Thanks in advance
 
Thank you for the reply but I'm having to work to a budget of £220 so good fullrange drivers are of the table. Also there's the issue of size as this is for his bedroom and he will need to transport them.

Thank you for the pointer though, i love Fane's drivers, Sherman Audio do great systems using them.
 
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Generally speaking an omni mic is suggested for speaker measurements, however if you put the AT-2020 directly on axis and do gated measurements then I think that it should be ok, even though it is a cardioid mic (it would not be appropriate for getting room effects though).

The mic looks to be quite flat from about 500 hz to around 10Khz based on Audio-Technica's specs so again for crossover development even without subtracting the mic response curve from the measurements I think it will give you good results. Certainly better than designing without measurements at all.

Combine with proper impedance measurements taken in cab and I think you will do just fine. The relative levels in your crossover region, and phase matching are what you should concentrate on, and not trying to adjust for any slight differences in upper or lower response.

I do all of my measurements with an uncalibrated home made mic wand using a panasonic WM-60AY capsule and get very good results. It does typically have a very flat freq response as shown in the attachment below...

Tony.
 

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The SB Acoustics drivers are usually off in T/S department, freq resp is much like SB graphs. Panasonic WM-60AY is OK, Mighty Mike II as preamp, ARTA, a few others. XSim is super easy to use once you have Zma and Freq resp files. There is that cheap mic for Cellphones from Parts Express, comes with calibration file, I would try this one.
 
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