Ok, in direct sunlight the membranes are loose. When I powered one up, dead silence, the other made a scratching sound. Added a source, did get music from both speakers, but still heard the "scratching sound" from the same speaker. The sound I now hear is that of a deflating ego.
All righty. You still got the deal of 2014, so don't panic. I'd pay you double your investment for those Gradient woofers without batting an eyelid.
First of all, what amplifier are you using? These speakers can send most amplifiers into protection, so be careful with that.
As for the speaker that is scratching, that means one of the panels is arcing. Power the speaker up, and listen closely with nothing playing. Is the scratching coming from the top, middle, or bottom? If you're really lucky, it's coming from the top..
These speakers have four panels in each. Taking them apart is simple, but make sure you ground the panels before touching anything inside. They can retain high voltages for hours after being shut off.
I'd take apart the arcing speaker, and remove the dust protecting membrane (you can replace that later with a simple window insulating kit). Power it up, and see if you can identify which panel is arcing. If you can't pinpoint it, don't panic. Shut it down, ground the power to the leads to eliminate the four thousand or so volts that are floating around, and remove the top panel. It's soldered in place with 8 wires, IIRC. When you've got that out, power it back up. If it's not arcing, then the problem is in the panel you just removed. You're lucky, because they get progressively more difficult to remove.
If it's still arcing, then repeat the grounding and panel removal for the second panel. Try it again until you isolate the arcing panel.
Note, there may be more than one panel that's arcing.
You can send the panels out and have them refurbed for a couple hundred bucks. Absolutely worth it for one or two panels. If you have more than a couple of panels arcing, then it might be time to learn how to refurb them yourself. The material and instructions are available online.
Good luck with these. They are amazing speakers when working properly.
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