This Sub itself works flawlessly, just as good as I remember it ever.
That being said, its definitely not the multimeter, I put in a new battery. Somehow I ended up with 4 sets of multimeter probes, so I tried different probes for the multimeter as well. I tested a bunch of other items for which I am certain of the expected readings, i.e. vape coils, computer parts, and multimeter performed perfectly. I couldn't take a photo of both the driver and with me having probes on them, but see below for pics(cropped it to lessen file size per forum image size limits). I literally took the readings over ten times and different points of the contacts. I even measured touching the tensils that run up to the terminals, as well as right behind the terminals. All reading gives me 111 or 110. Lastly, I have scratcher tool for something else, I used it to take a bit off the terminals in case it is oxidation or just dirty, but again same reading afterwards.
I then went around and checked a bunch of others, they all read 3.5 to 3.9 which makes sense from what ive read that whenever its listed as 4 ohms, it will read a bit below, which was lovinthehd above also noted.
This is an old sub, and couple of times I put up on ebay for a few weeks, twice someone asked me what the impedance was & I tried to look it up all over the web without success. Perhaps the fact that the manual and old sales postings don't list the impedance in the specs, means its something like what TLS Guy...
"...high impedance driver"
I found another Def Tech driver that looks identical but is a 15 inch version on ebay & the impedance is listed as 75 ohms for it
HERE
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