While playing song,
I would disconnect either one of the cable and again found absolutely no difference.
So at the moment I still remain convinced that as long as you use good copper wire,
Sir,
First;
Congratulations.
You have purchased a great product.
I am happy for you.
Before you try anything, position the gear 'appropriately'
The Amplifier needs to be on a strong & leveled platform.
The Speaker needs to be at least 24" from the rear & side walls.
If you can give it 36" to 48" it will be better - however, your room will not
allow that.
The procedure to do a 'cable' test is incorrect.
You cannot use a 'splitter'
You will physically have to change cables 'each time'
Please do remember, the more you respect your gear the better results it will show to you.
You have already paid for the gear - that is the 1st step.
Now the difficult part starts - setting it up & fine tuning it.
To give birth to a child is the 1st part, the raise it & teach it & nurture it is the difficult and challenging part - so is the case in audio.
The money was spent - now spend time & efforts.
All the Best !
p.s. Even the power cord that connects to your ESL - when changed - the sound will change...Do not use a MX Power Spike Guard or the likes for power supply to the audio gear.
Do not run power cables & I/C's & Speaker Cables together - parallel - please...