Martin Logan ESL upgrades

The cheapest Martin Logan ESL is a good value for the money. Can we make it a little better with a little effort? These are the things I successfully tried:
  1. Linear power supply. You don't even need to buy that fancy 'audio' power supplies. A normal, stabilised, linear (with a transformer) power supply also helps a lot. I tried something for $10, 15V, 1A, with a 5.5/2.1mm DC plug, plus in the middle.​
  2. Bass is probably the part where ML ESL is the weakest. We can at least try to mitigate some problems here. Adding a weight to the speakers could help. I had granite coasters laying around, that almost fitted perfectly. Also, it seems that the enclosure has some resonances, so I added self adhesive bitumen pads inside. That was very helpful for quality of the bass. When being at it, changed the filling to wool.​
  3. Unfortunately I couldn't place the speakers far enough from the wall. The back wave was messing the sound too much. Ideally it should be diffused behind the speakers somehow. Probably with some acoustic system on the wall. Anyway, I couldn't find anything aesthetically pleasing enough. I had to damp the back of the panel with an acoustic mat. It worked well for the purpose.​
  4. Next step was checking if bypassing the caps in the crossover can be beneficial. The result was also promising. Caps bypassed with 1% of the original values. It helps with resolution and smoothes the highs.​
Do you have any other modifications that can be easily tried?
 

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Hey, as a fellow Martin Logan modification enthusiast I HIGHLY recommend defeating the internal passive crossover on the woofer and driving it with its own amp with electronic crossovers. This is how ML powers all the big high end models and it really brings the bass to life.

I personally use a Crown XLS 1002 pro amp, it has a full electronic Xover suite built in. This really brought my speakers to another level and I will never go back. I actually use a Dayton DSP/Xover unit do all the Xovers on my entire speaker with no passive crossovers at all.
 

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Hi there Xed, I've just joined the forum so I could ask you if you'd mind giving some more details of your ML ESL mods, please? I agree with your comments on their bass performance; definitely some resonances there. I'm waiting for my Ali Express dc power supply to arrive and the wool wadding and anti-vibration material has been delivered - but I haven't opened up the ESLs yet. What are the four pads on the pcb in img_0499? Did you fit them or are they ML originals? Where did you source the capacitors (and their values - can't make two of them out from your photo) please? I have my ESLs across the corner of a room - so the rear reflections are (I think) firing way off axis. I have a pair of ML re-Quests in my basement with a pair of heavy rugs hanging behind them (on curtain rails 10 or so cms from the wall) which adequately suppress the rear reflection problem.