HELP AFTER MY MODS, My tweeters are subdued and weak-

Ok,  thanks Sean...again, my argument isn't that ESR doesn't matter, My argument is that it isn't enough to do this.  So, you are saying that you replaced your midrange electrolytics and your tweeters returned? 
To be clear in my own pea brain.

Ok,  I have avoided trying to come off as a know it all.  I don't want to be that way,  nor known to be that way, but I'm going into teaching mode....We are combining some difficult theories with some very elementary basics. 
I'm going to speak only as thought this is a tweeter.  
You have a 6 ohm tweeter and it is too sensitive to match your mid range or 2 way woofer,  The way that most designers handle this is to add an Lpad to match sensitivities,  then properly build a crossover for your 6 ohm tweeter to the woofer or mid.
Another way to do it if conditions are right is to add a 2 ohm resistor... The resistor adds a pad to the tweeter, effectively turning it down and also add resistance so that you can now use an 8 ohm crossover.  So 2 birds are killed with one stone.  In this scenario,  extra resistances reduced the tweeter output and raised its impedance.  
So now,  ESR. l When I build a crossover,  I do compensate for ESR,  but it is more for exact matching crossover points than the bit of gain difference,  even so, I try to match gain correctly also. 
So, when Sean replaced the Electrolytics or any of his current caps,  the replacement caps had lower ESR resistance... The argument being made is that the reason his output is diminished is that the resistance is so far off that it is reducing the output of the tweeter. 
Ok, to start with, the resistance on his new caps are much lower,  what that means is that there is less of a pad,  adding resistance will be helping to reduce the output back to the level of the original caps.... Next,  we discussed the crossover point being changed,  if that happened with the exact same value of caps,  his crossover point would be effectively lowered meaning... So, lower crossover point means more perceived output,  less resistance means more output.  Significantly lowering ESR in theory would make his tweeters louder.  I hope this all makes sense.  Tim 

Tim, my guess is a combination of difference of ESR and those old electrolytic caps dried out and out of specs, so a tester that can check the value of the caps and ESR will give us the answer.
One thing that surprised me was the cables made such a big different ...

@imhififan  ... well, again,  ESR should've had the opposite effect.  The old caps matter, plus his Tara Labs are solid core.  Typically solid core are not as extended on top,  plus those Tara labs have some sort of circuit in them... But overall, you are correct, the Tara Labs should not have made such a big difference, unless there were other problems involved. Solder joint or one of the big caps out of phase or a combination is my best guess.

Idahifi's experience is exactly what I've been talking about. :)

In a 2nd order hp filter, this problem occurs from a combination of:

- Very low DCR in the coil
- Very low ESR in the caps
- Too small a resistor in series with the cap
- The impedance of the next stage higher in Hz.

In the right combination of things, you end up with far too low an impedance in the next stage.

Of course, having a monstrous amp fixes this issue, but you'd be surprised how just a little dip around 3 Ohms or less can do this.

Inexperienced modders get themselves into trouble by trying to get the lowest possible coil DCR and cap ESR without understanding the entire circuit, and bam.

Best for them to only replace series caps. There may be some level shifting but it is more benign.

Best,

E