Not to fi they arent ...the customer yes
There is absolutely no way in hell they're reconeing a speaker for 10$ If you know a way to do that you will get rich quickly selling recones for 50$ and undercutting everyone else by half.
trust me, it costs fi more than $10 in parts for a recone. just the coil is about $10
If you buy 100 coils the price of a 4 layer 3" is close to 30$ , I can't imagine them dropping down to 10$ even if you bought 10,000 at a whack. Really I doubt you could get garbage quality Chinese coils for 10$
i am curious if anyone else has had a coil let loose from the former, and what the circumstances were/are.
I have twice (and I break a lot of woofers), both 18" woofers, 5KW and up pushing hard, and they stunk bad before they let go.
Sounds like a lemon to me ....ive seen lots of spider issues but no coils lettig loose..esp on that power..and i kno this is far from ur first rodeo so id say they are just jewing u around ....every company no matter how reputable has issues like this..just ***** fi chose to go about it this way
Maybe Fi is backed up and subs are getting rushed. If you set with a DMM for 1000 per coil I doubt you where getting over RMS. to me it sounds like they skimped on assembly.
If this is manufacturer defect it is in the coil and nothing Fi did or did not do. Anything over 1200W continuous power will make a 3" 4 layer coil fail, Once you cross that threshold of where it can't dissipate heat fast enough they will overheat and fail quickly, exponentially faster as you increase power or decrease cone movement (cooling)
no, id rather not "trust you" coils bought from precision, when bought in the bulk fi buys in are about 3-4 dollars each.
Calling ******** on this without some sort of proof.
how many have seen a coil unwind and what were the circumstances? how many have had a brand new sub fail within hours and why was it (besides pure SPL destruction purposes)?
obviously, to get the coils to unwind they need to be hot enough for the glue to let loose. the amps never went into protect and the coils aren't shorted. they weren't ran long enough to overheat from extended use (only pushed a few minutes at a time). if they coils were mis-matched, one coil would heat up more than the other. that is the only concrete evidence we have right now, mismatched coil DCR.
I've only ever had coils go slinky from gross abuse. I've had some subs break within a short time after building them, but that's mechanical from either me being abusive or trying to skimp on glue. Of course you would know if it was a glue issue.
wast most of the music/burps around 50Hz or so? If so did you notice very little excursion out of the sub as that will create a lot more heat with little to no movement to cool the sub.
Could just be a case of too much power/too little excursion and the sub overheated and let go. BL's aren't exactly killer strong subs...
My thoughts exactly, and a worthy topic. One of the reasons I don't like 18" woofers, really. Side by side a smaller cone will move more and cool better. I find smaller drivers hold thermal power noticeably better than larger (assuming same motor, coils, and suspension).
good questions. music covered a wide range and the tones weren't that long in duration. clipping didn't happen, i'm sure of that. scopes don't lie. and nothing was black, coil looks new just unwound.
there was plenty of cone excursion with initial testing around 50Hz, and i agree that the coil would heat up if the cone wasn't moving to create airflow to cool the coil.
maybe i need to take a closer look at cone behavior in the box and if the cone seems to "stall" around certain frequencies. even still, i would expect it would take longer, since the music was constantly changing and the tones were higher.
the intent is a daily system, not an SPL monster. Box is tuned around 28Hz. The sub in there now does just fine.
Coil does not need to look black to have failed from heat, though almost always you'll get some smell before they fail from over-heating. Consider smaller drivers move more on the same power and cool better.
If they are using 8-layer flat wind coils from Precision in Florida... the coil itself is 2.5-3x that much. A 4-layer round is still 1.5x that much if it's fairly long.
Either way -- they do use Precision coils at Fi; I am just not sure what type in that model driver -- Precision makes some of the best coils available and a coil that is simply defective is almost unheard of as far as a coil just sliding off of a former.
So that would leave us to figure out how the coil got so hot so quickly.
When you used the scope did you test it on the music signal as well in case the level was different ? The amps made in the style of the Massive Nano (similar design to Audiopipe) make a VERY weird and jagged wave with spikes when clipped on the ones I've tested. We did some testing here a few weeks and when we pushed amps of that design into clipping the coil smelled rapidly; same clamped power on a Korean Class-D (which clips very smooth and flattens out up top) no such smell.
Either way; good luck resolving your issues //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
This is the most accurate explanation of cost of coils and most likely explanation for cause of failure. I wouldn't rule out that Precision made a dud coil, but this seems most likely.
---------- Post added at 10:36 AM ---------- Previous post was at 10:35 AM ----------
:roflbowdown: @ people paying more than 3-4 for a precision 3" coil. You guys are high.
I guess Jacob doesn't buy enough of them to know what the real price is right? Please tell me how I can get my coils for 3-4$.