this measurement refers to the second type of crossover, with a different approach than the one you saw above and you can see how it has difficulties on the low range. it sounds very good, in the medium-low and high range and is well balanced, but below that deficiency is immediately noticeable.
The plot technique is looking better.
What does your bass look like if you put the mic very close to the cone and measure? Have you looked at your room effect?
What does your bass look like if you put the mic very close to the cone and measure? Have you looked at your room effect?
move the mic closer to the woofer, I haven't tried it yet. for now I've kept levels and distances to see the differences between the two crossovers - the mic is on the X and Y axis between the tweeter and the woofer. and no room control at the moment.
Ok. When you are ready, putting the mic close (less than 1cm) will tell you the bass response without the room. You can learn what is causing your problem.
😆
I'd rather take the yellow cones and use them to make swallows' nests.
i think i'll try a third crossover - i can already make a modification to the first one (green) - i think i can get some more low frequencies out now that i've understood how this yellow cone behaves with the various resistors and capacitors and fine tune the tweeter, based on crossover n°2 which actually sounds better. then i think i'll place an order for capacitors with values between 0.2uF and 10uf so i can try them all. if you see that the capacitor market will have a price spike you'll know it was me.
I'd rather take the yellow cones and use them to make swallows' nests.
i think i'll try a third crossover - i can already make a modification to the first one (green) - i think i can get some more low frequencies out now that i've understood how this yellow cone behaves with the various resistors and capacitors and fine tune the tweeter, based on crossover n°2 which actually sounds better. then i think i'll place an order for capacitors with values between 0.2uF and 10uf so i can try them all. if you see that the capacitor market will have a price spike you'll know it was me.
My two cents. Given that chances for a mic manufacturer to build their own electret capsules are thin, it's likely they use ready available parts and in my understanding these fall to just a few categories regarding frequency response irregularities. If one could find the exact part then the calibration file should apply. That is in my opinion of course. But I built a mic based on that and generally I'm satisfied.
Measuring known speakers, I got a rough idea about its generic frequency response.
Something like that. Then I downloaded a commercial calibration file and edited it with a text editor. Simple as that.
When loaded in ARTA it looks like this
Accuracy of this method depends on the reference used, preferably another known mic but what I did works for me.
Measuring known speakers, I got a rough idea about its generic frequency response.
Something like that. Then I downloaded a commercial calibration file and edited it with a text editor. Simple as that.
Accuracy of this method depends on the reference used, preferably another known mic but what I did works for me.
It's built mostly with what I had available. As you said, a piece of an FM antenna holds the electret mic with heatshring tube, and then a screened cable goes to the preamp inside the aluminum box. The tripod comes from a laser leveler, it expands to more than 1,5m high. The preamp is simple, based on OPA2134. One half is used to take balanced output to drive a long interconnect.
It requires 5V external power supply, for example USB. It has a DC converter to +/-15v for the opamp and a separate 9V regulator for mic.
The triangle shape means that you are measuring all the room reflections You want your gate time to be about 5ms (depending on how far away the reflecting planes are) after the start of the pulse, not 400-500ms.
Also, if you are still using the cardioid mic, proximity effect is going to alter the frequency response of your close mic measurements at the low end.
I am done here peace out.
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No. If the 'calibration file' isn't linked to a single particular mike, it is mostly useless. I've designed & built commercial measurement mikes and have a good idea how much they vary from sample to sample and maker to maker.
The smaller the omni capsule, the less likely the response will deviate from flat at HF. So a 6mm omni capsule is more likely to be flat up to 20kHz than a 10mm capsule. (That's not to say they are always better. I've seen some shocking 6mm capsules)
The most consistent 6mm capsules were Panasonic WM61s which were used (specially selected) by Earthworks for their early measurement mikes. Sadly now only from Ye Olde Unobtainium Shoppe
I don't think another cheapo capsule has emerged with the same level of consistent performance.
But even for WM61, there are variations. IIRC, there's a couple of old webpages which show how they vary.
If you use a cardioid capsule, all bets are off.