So i bought two BNIB Faital HF204 in February and was only able to hook them up into my K402 horns. One of the speakers sounded normal, but the other one completely lacked high frequency extension. It was very obvious, but i ran a REW sweep and this is what i found:
I tried swapping amp channels and channels on the source, but it sounded the same.
How is it possible for a CD to be damaged like this? I always thought it either works or just doesn't. Maybe, it was damaged during transportation? Like fallen, shaken?
I tried swapping amp channels and channels on the source, but it sounded the same.
How is it possible for a CD to be damaged like this? I always thought it either works or just doesn't. Maybe, it was damaged during transportation? Like fallen, shaken?
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A dropped driver may have a shifted pole piece, which would pinch the coil, resulting in a lack of low end.
There are several possibilities for reduced HF and peaky response.
A poorly made imitation aftermarket diaphragm could have lousy frequency response.
It is possible the Diaphragm to Phase Plug Space (DPPS) has been increased by placing shims beneath the diaphragm. That would allow more excursion, more low end response before the diaphragm contacts the phase plug, but also the extra space causes an acoustical band pass, rolling off the highs steeply.
Enough accumulated gunk in the gap or damping material contacting the diaphragm could cause HF loss.
"Dried up" (gummy) ferro-fluid could dampen HF.
Inspection, cleaning, aligning are all part of the DIY "fun" ;^).
There are several possibilities for reduced HF and peaky response.
A poorly made imitation aftermarket diaphragm could have lousy frequency response.
It is possible the Diaphragm to Phase Plug Space (DPPS) has been increased by placing shims beneath the diaphragm. That would allow more excursion, more low end response before the diaphragm contacts the phase plug, but also the extra space causes an acoustical band pass, rolling off the highs steeply.
Enough accumulated gunk in the gap or damping material contacting the diaphragm could cause HF loss.
"Dried up" (gummy) ferro-fluid could dampen HF.
Inspection, cleaning, aligning are all part of the DIY "fun" ;^).
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Hey weltersys, thanks for chiming in.
Low end! But i am having problems with HF. So, not shifted pole piece.
I bought the driver from official seller, so not an aftermarket diaphragm.
Those shims are placed intentionally, right? Kinda doubt they sell modded drivers 🙂
But this happens with age, right?
Right, the only thing left to do. Will need to ask the seller if openning up the driver clears the warranty. Otherwise will have to send it back to him and wait...
I have a 100uf cap connected in series as a means of protection against clicks, pops and DC. Is there a way to somehow poorly connect the cap so that it filter high end instead of low end?
Low end! But i am having problems with HF. So, not shifted pole piece.
I bought the driver from official seller, so not an aftermarket diaphragm.
Those shims are placed intentionally, right? Kinda doubt they sell modded drivers 🙂
But this happens with age, right?
[/QUOTE]
Right, the only thing left to do. Will need to ask the seller if openning up the driver clears the warranty. Otherwise will have to send it back to him and wait...
I have a 100uf cap connected in series as a means of protection against clicks, pops and DC. Is there a way to somehow poorly connect the cap so that it filter high end instead of low end?
"Is there a way to somehow poorly connect the cap so that it filter high end instead of low end?"
Sometimes with test rigs I attach parts together with a loop of scrap wire, and this can cause partial signal loss, probably because the signal has to get through a poor join or layer of corrosion.
Usually if I improve the connection or play it louder for 20 seconds, the issue clears up.
If your stuff is firmly mounted, it is probably not that.
Sometimes with test rigs I attach parts together with a loop of scrap wire, and this can cause partial signal loss, probably because the signal has to get through a poor join or layer of corrosion.
Usually if I improve the connection or play it louder for 20 seconds, the issue clears up.
If your stuff is firmly mounted, it is probably not that.
That is gross.
Weltersys suggested possible errors hold firm because what you hear and much better measured is there.
I suspect a returned unit resold as new, where a former user messed with it, maybe he burnt it and cheaply repaired it swearing he didn´t touch it (I deal with such lying custoners every week) but in any case, do not waste time, send it back to seller for replacement, that´s what warranty was invent for.
Absolute worst case, have them repair it with a real Factory part.
Know what NIB means but not BNIB, care to explain it?
That said, given time between February and today, they might refuse repairing it or claim you damaged it, but let them inspect the unit.
EDT: just for sake of completeness measure *the other* driver in same horn, post curves for comparison.
Weltersys suggested possible errors hold firm because what you hear and much better measured is there.
I suspect a returned unit resold as new, where a former user messed with it, maybe he burnt it and cheaply repaired it swearing he didn´t touch it (I deal with such lying custoners every week) but in any case, do not waste time, send it back to seller for replacement, that´s what warranty was invent for.
Absolute worst case, have them repair it with a real Factory part.
Know what NIB means but not BNIB, care to explain it?
That said, given time between February and today, they might refuse repairing it or claim you damaged it, but let them inspect the unit.
EDT: just for sake of completeness measure *the other* driver in same horn, post curves for comparison.
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I take BNIB to mean "brand new in box" meaning that the manufacturers seal, on the box, is not broken.