FYI, I'm using a M74B with 1st order XO at 1khz. It has no other protection.
The system was pushed a couple weeks ago during an intense 2+ hr session where some electronic tracks reached 110 dB SPL at 12-14' distance. That suggests at least that SPL at 1m distance from each speaker.
I was a bit concerned about heat or excursion damage to the M74B but so far no sign of any damage. It's a robust mid!
The system was pushed a couple weeks ago during an intense 2+ hr session where some electronic tracks reached 110 dB SPL at 12-14' distance. That suggests at least that SPL at 1m distance from each speaker.
I was a bit concerned about heat or excursion damage to the M74B but so far no sign of any damage. It's a robust mid!
Keep an eye on the group delay with filters in this range as what looks ok on paper may produce a more disappointing sounding result.
Well, think of a resonant system driven by a (linear) engine. Below it’s resonance, the excursion is a pretty linear function of compliance and power. Since compliance is (almost) constant, the power applied dictates the excursion. Hence the excursion stays constant. The mass plays a very secondary role and even more so the air impedance on the dome.
Well, since this is an active speaker with FA253, it is very easy to test and measure various highpass versions. Both the system and single driver, at mid and high spl.
When looking at only mid's distortion, %-graph can look scary because when fundamental spl goes down % jumps...
System response naturally requires respective changes to other drivers too.
When looking at only mid's distortion, %-graph can look scary because when fundamental spl goes down % jumps...
System response naturally requires respective changes to other drivers too.
Ordinarily, I wouldn't recommend this for beginners. It's a shortcut that could prove dangerous.
But for moderate to experienced persons, this is one alternative to checking the lowest practical crossover point for tweeters or midrange or woofers, IF one wants to be guided by maximum THD/maximum SPL, without destroying the driver.
Advantages- doesn't stress your microphone, or your driver.
Disadvantages- YOU MUST check absolute voltages with a multimeter if you want to proceed.
measures THD with a sine testing only, questionable correlation with sonic performance or /psychoacoustics.
But for moderate to experienced persons, this is one alternative to checking the lowest practical crossover point for tweeters or midrange or woofers, IF one wants to be guided by maximum THD/maximum SPL, without destroying the driver.
Advantages- doesn't stress your microphone, or your driver.
Disadvantages- YOU MUST check absolute voltages with a multimeter if you want to proceed.
measures THD with a sine testing only, questionable correlation with sonic performance or /psychoacoustics.