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View Full Version : Array 800 - Repairing a pair of Bobbleheads



HCSGuy
04-16-2011, 05:11 PM
As some may know from the "K2-S5800/K2-S9800 On Sale" thread, I ordered a pair of Array 800's from Harman's clearance sale that had loose heads. On the 1400 Array, the head ships separately, you attach the head to the enclosure and cover the screw with the adhesive horn emblem - once it's on, you can't take the head back off. On the 800, the head is factory installed, but not supported sufficiently by the packing material to prevent damage in shipping - I suspect that knocking an upright box over in any direction would loosen it up.

I purchased (I think) about the second to last pair they had, so I assume no replacements were available. I also assumed replacements would have a good chance of being damaged. After disassembling them, a repair seemed pretty straightforward, so I figured I'd document it here in case someone else needs it. My goal was to repair them in a way that didn’t require the adhesive emblem be removed/ruined, and that could be undone later, if need be.

By the way, I realize there are other, possibly better ways to execute this repair - I am not going back and redoing them, but welcome input. I understand there are those here who would mill new pieces in stainless, turn them in ironwood, or CC the networks while the speakers were open, but I’m not any of those people, though I wish I were:p

First, some pictures of one damaged speaker, and the removed head. You’ll notice from the removed head that it was held in place by a threaded insert that was screwed into the MDF of the cabinet top, and also from the back by a L bracket that was also held in place by smaller threaded inserts. IMO, screwing threaded inserts into MDF does not maintain adequate structural integrity – T-Nuts from the back would have been much more robust.
Damage to the cabinets:

HCSGuy
04-16-2011, 05:14 PM
Next, the Head, with the original threaded insert. After removing the rubber plug and cap head screw at the back of the horn, the head pulled right off, allowing me to unplug the head wires – the threaded insert had no purchase to the enclosure whatsoever. As the repair would require me to remove the threaded insert from the speaker head, but I could not remove the emblem, I sought to remove it without access to the head of the screw. The first one was simple – grabbing the threaded insert with pliers and pulling down while turning worked, there was enough friction on the head of the screw that I was able to unthread the insert. The second one was tougher as the threaded insert was tightly bound to the screw, so that twisting it turned the screw as well. For this one, I cut a slot in the end of the screw with a micro hacksaw and used a small slotted screwdriver to hold the screw still while unthreading the insert.
Pictures of the head with the original insert, and with my solution – a threaded coupler going through the hole in the cabinet and being held in place by a screw and fender washer from the back side. This picture shows a cut washer, which I though I’d need to get in the tight corner where the screw would go, but I found an uncut washer would just barely fit. Also, I had to shorten the new threaded insert to slightly less than the thickness of the wood (3/4”), and cut the 1/4x20 screw to about 5/16” of thread so that it would tighten without hitting the head screw threaded in from the other side.

HCSGuy
04-16-2011, 05:16 PM
I removed the top panel of the speaker (8 metric cap head screws into T-Nuts and a mallet). I cut the material off that was flaring out of the hole past the front surface so that the head would reattached to a flat surface. I also opened up the hole very slightly so that the new threaded insert would shove in with some friction. I reattached the speaker wires and put the head back in place, then carefully got the new screw threaded in position – I found I had to use a small straight blade screwdriver to turn the screw at the extreme angle required as my fingers could barely fit in to turn the screw. I tightened the screw with a small 3/8” end wrench, 1/12 of a rotation at a time.



A few opinions – first, the cabinet has inconsistent manufacturing design – as previously mentioned, the head is held to the top panel with inadequate fasteners, but the top panel is an assembly of four different pieces, held to the cabinet with 8 machine screws and T-Nuts – it’s as if the cabinet was designed and build for conventional front panel drivers, and someone had to retrofit head to the cabinet after it had been built. Also, the woofer is held in with pan head wood screws instead of machine screws and T-Nuts.

HCSGuy
04-16-2011, 05:18 PM
Lastly, but the top Panel back on, reinstall the woofer, and do some listening! I set up a quick system in the office and stayed up way too late listening to Melody Gardot’s “My One and Only Thrill”, Paul Simon’s “So Beautiful or So What”, and the Tron Legacy soundtrack, trying to get the woofers to blend, so far with limited success Next step is to move the Arrays on to stands and move the woofers around.

hwirt
04-16-2011, 06:56 PM
Great write-up HCSGuy, your repair looks to be better that new. Also the woofers and the Array 800's look awesome together. Reminds me of GT's living room setup.

SEAWOLF97
04-16-2011, 07:11 PM
nice documentation & workmanship ..... did JBL give any concession (discount) for your damaged purchase ?

Titanium Dome
04-17-2011, 12:03 AM
I like a good story with pictures. Nicely done!

HCSGuy
04-18-2011, 08:58 PM
SEAWOLF97
nice documentation & workmanship ..... did JBL give any concession (discount) for your damaged purchase ? I didn't even ask - I figured it would take longer to make my case with them than it would just to fix them, plus the odds were too high that the replacements would come busted too.


hwirt
Reminds me of GT's living room setup.I set them up that way just to pay him homage. I've since moved the Arrays to stands and am playing with woofer placement to get better bass- there's more than enough of it, I'm just not getting a good transition between the speakers.

Now that I've listened to them, the Arrays aren't bad, though I really wish I could try some 1400's in my room for a while, I think they would shine in every area I think these fall short on - midbass quality, lower male vocal weight, that's about it. These 800's aren't bad - midrange and up they are really seamless, and the HF detail is amazing - far better than anything else I have except maybe he Ti2k's. Makes 2405's hard to listen to :o:. They definitely aren't efficient, and the woofer runs out of steam, even run through the NHT X1 crossover's 12 db/octave HP crossover set at 80hz, I hear woofer suspension noise coming through the port at pretty high volume on the Tron Legacy soundtrack. I should probably measure how high, as it may be louder than I think - though nothing else is breaking a sweat.

If I had it to do again, I would have bought a pair of S5800's and sold off some stuff for the difference - these are good, but no goose bumps :dont-know:

4313B
04-19-2011, 09:57 AM
If I had it to do again, I would have bought a pair of S5800's and sold off some stuff for the differenceI considered doing the same.

Titanium Dome
04-19-2011, 10:19 AM
I really wish I could try some 1400's in my room for a while, I think they would shine in every area I think these fall short on

If I had it to do again, I would have bought a pair of S5800's and sold off some stuff for the difference - these are good, but no goose bumps :dont-know:

A. You are right about the 1400s.

B. The S5800s would have been sweet.

C. You still got some cool gear. :yes: