The making of: The Two Towers (a 25 driver Full Range line array)

Glad to hear your procedure went well.

Its hard to imagine why drivers would fail due to handling; semiconductors are known to be susceptible; drivers should be robust. Given the wiring, they all see the same electrical hazards. High temps in garage storage space?
 
Temperatures in the garage haven't been crazy, it is cooler there than my living room in the summer time. As said, I can't even begin to imagine what has happened. They survived 6 and a half year of abuse without a glitch, played almost daily. I've opened them up several times in that first year, nothing bad ever happened.
I'll move on without trying to find this answer...
 
Speaker news again 🙂.

Had my last procedure early morning last Tuesday and I am recovering well. So well, actually that I decided to mount some drivers on the baffle. I got them all hooked up and what do you know....

Again the impedance showed a one group failure. The average low impedance hoovered around 8 ohm instead of 6.something... I figured I must have messed up wiring them all up again, nope... quick group tests showed yet another driver failure in a previously untouched (and fully functional) group.



Enough for this day, I'll call it a bingo and will try not to worry or guess why I lost another driver yesterday 😕. (that's 3 in total)

Congrats on recovery going well !!!

What's the nature of the driver failures? Open coil?
 
The TC9 driver sure has changed over the years. My originals, bought new in 2011 have a more sturdy frame than the new version, bought 10 years later.
The TS parameters seem slightly different too, as their impedance peak lands a little lower than on the old drivers. Hope it doesn't bite me in the, well, you know..
This little fact made me change the first broken driver in the center position (the group without filters) by one of the upper most drivers (that's doing bass only after filter placement). When one of the drivers in that group turned out to be broken too, I decided to replace all of the upper 5 drivers (impedance matched to each other, I already missed 2 in that group)

The third driver I replaced was a member of the bottom most group, there I just replaced it by a hand picked sample (closest match in impedance plots). So I guess the results won't be much different due to these small differences within the driver properties.

Just clearing my head here... 🙂
 
Closed up the left speaker again, measured it more than once to be sure 😛...

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Red is the right one, the lighter green the repaired left array. Orange is free baffle impedance of left array.
Looks like she's firing on all cilinders again.

So far, so good. Now waiting for some help to get it back inside. Not going to do it by myself this time.
 

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I didn't quite go far enough. I checked the braided leads to the connector tabs, cut the surround and spider to see the coil. Nothing wrong there. I guess I should have removed the dust cap to see the connection between braided leads and voice coil.
Doesn't look like an easy task to be honest, not like the drivers in the thread I linked to.
 
LOL!!! Dude - so glad to see you still have your sense of humour!!!

Yes - there does appear to be quite some resistance to what I feel is a reasonably logical conclusion!

I think we are there now though - with all the measurements, studies and SL's modelling - I feel without a doubt we can see that the clamshell config has a role and benefits (size/SpL) - just within the recognised constraints of cost!

You notice I haven't even attempted to go down the reduced distortion road yet - that will be for another day!

I don't know if I ever thanked you for introducing me to infected mushroom - but if I didn't..........Thank you!!! I was loving some of their earlier albums last night!

Be well, your thread has moved on so much - I will need to put in some reading to catch up!!!
 
I've got a friend coming over tomorrow that's going to help me move the speaker indoor again.

If, and that's still a bit of a question, if the drivers were damaged from transport, I figured I needed a bit of safety/protection this time. Especially since I'm not the only one carrying the speaker this time.

So I figured out a way to protect the drivers:

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That should help prevent little mistakes as to grab a cone by accident...
Need to be extra careful with the bottom 3, lol... I think this should help, fingers crossed!
 

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LOL!!! Dude - so glad to see you still have your sense of humour!!!

Yes - there does appear to be quite some resistance to what I feel is a reasonably logical conclusion!

I think we are there now though - with all the measurements, studies and SL's modelling - I feel without a doubt we can see that the clamshell config has a role and benefits (size/SpL) - just within the recognised constraints of cost!

You notice I haven't even attempted to go down the reduced distortion road yet - that will be for another day!

I don't know if I ever thanked you for introducing me to infected mushroom - but if I didn't..........Thank you!!! I was loving some of their earlier albums last night!

Be well, your thread has moved on so much - I will need to put in some reading to catch up!!!
Same hear. Never heard of Infected Mushroom until this thread and now really like the music.
 
I passed it on... I learned about Infected Mushroom from a fellow audio enthusiast on the DIY Mobile Audio forums 😉. He introduced me to the song: Avratz from the album Converting Vegetarians. That, and many more of their songs started to appear on my play-lists.

I'd rather play these than the nth audiophile favorite 😉. In fact, I actually love Infected Mushroom.