So I have a SoundTech 2 way 15" woofer with horn loaded compression driver tweeter. Looking at the crossover looks like it's not optimal to me. Treble is soft with a simple 1st order crossover at around 7-8Khz that I can tell. It uses a 2.2uF series cap in tweeter circuit. Tweeter is 8ohm. Also has a 16ohm padding resistor across tweeter. So am I miscalculating the crossover point and shouldn't it be more like 2-4 Khz?
2.2uF into 8 ohm would indicate 9,000Hz.
2.2uF into a parallel resistance (8//16) of 5.3 ohm would indicate 13,500Hz.
Are you sure this is not a piezo driver?
2.2uF into a parallel resistance (8//16) of 5.3 ohm would indicate 13,500Hz.
Are you sure this is not a piezo driver?
Yeah it is a Fostex 025H08. Uses a replaceable textile dome. So what would make more sense for a 15" W and 1" T. Being 1st order I could see a little higher but I would think at least 4Khz. The tweet is rated for 120W
I'm not having any luck obtaining information on a Fostex 025H08 - do you know its resonant frequency (fs)?
A 2nd order high pass would make more sense in order to bring the crossover point as low as possible without stressing the tweeter.
A 2nd order high pass would make more sense in order to bring the crossover point as low as possible without stressing the tweeter.
4th order LR is IIRC the lowest stress on the highpass section.
Anyway, I'd suggest that such a simple crossover might indicate a lower-quality product, so I'm not sure how much time & effort should be put into this.
If it was mine, I'd fire up the measurement mic and see what's what.
Chris
Anyway, I'd suggest that such a simple crossover might indicate a lower-quality product, so I'm not sure how much time & effort should be put into this.
If it was mine, I'd fire up the measurement mic and see what's what.
Chris
Sounds about right.
A driver in a horn usually rolls off past a few kHz depending on how small the dispersion angle is due to the horn. So you can do a single pole high up, it makes the freq response flatter.
You are crossing to a 15”, and pa (high volume) is interested in not burning up tweeters.
I cringe seeing a pa speaker run a 15” up to 4khz.... or a 12” past 1.2khz.
You could get a cheapie eq and active crossover, try for 2khz 24db then eq it to how you like it.
A driver in a horn usually rolls off past a few kHz depending on how small the dispersion angle is due to the horn. So you can do a single pole high up, it makes the freq response flatter.
You are crossing to a 15”, and pa (high volume) is interested in not burning up tweeters.
I cringe seeing a pa speaker run a 15” up to 4khz.... or a 12” past 1.2khz.
You could get a cheapie eq and active crossover, try for 2khz 24db then eq it to how you like it.
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