Sorry if I've gone on a bit too much :)
I think they probably won't change the sound as the hinge chamber and wiring chamber are sealed and not part of the acoustic area. Maybe there's some reverberation in them? They used some silicon sealer to seal around the sides of the block where the solder tags are. I can only presume that pokes through from the speaker area and has the voice coil wires in it.
Those photos are from a French website who offer the mod as a service to their customers.
I was planning to block the hole by having a tube made that fits into the hole and has the wires going through it's middle.
Or that may be too difficult. Just now I fitted the inner metal part from a screw down joiner (chock block) into the chamber and passed the wires through it. Looks promising. Will rattle so needs some padding. I have some foam strip to try fitting in there somehow. I might try shaping that so it wraps around the wires and protrudes through the hole.
I don't want to make it overly permanent as I would like to try different wires.
I think it's very difficult to measure the changes within complex music signal. A lot of what we hear might be difficult to capture and display in a graph.
Whilst it's no doubt useful in some ways, a sine wave at a frequency or a sweep frequency doesn't show all that much really.
I think there's energy storage in the sheath that is released and causes a smear that was can hear.
Ben Duncan ( http://www.benduncanresearch.com/ ) did some measurements of 5 metre speaker leads and was able to show a variance in time delay between a sine wave signal being sent and received. He showed different delays for different cables.
Distortion makes a sound brighter or warmer. It might still have the same sine wave but varying amounts of smear. The lower the distortion, it seems to me, the quieter the bass and treble.
Having more strands blurs the sound. Thicker sheathing. Polarity of the wires has odd effects with the tonal balance of the mid changing compared to the top and bottom.
With a friend who owns a professional recording and mastering studio, we've done loop back tests of cables. It's a pretty good way to hear even the smallest of changes because he's able to record the signal, as you suggest. It does show the wave forms, though we've never looked at that for differences, maybe some software could compare the samples but we use our ears.
What we do is have a recording on the hard disc then play that through the test cable and record it again back to the hard disc. Use the same XLR connectors, solder, different wires, polarities, thickness's of wire, number of strands, etc.
To compare, he can align the samples and original recording so they're all playing back at once, then toggle between them by clicking a software switch. No remembering the sound whilst changing leads, etc, is required, large or subtle nuances are all instantly laid bare before one's ears.
He found that it takes 400 hours playing before a new varnished silver lead doesn't change any further. He recorded a sample every 50 hours then compared them all.
We've been doing it for a few years and he's tested various makes both low cost and very expensive. The winner at the moment is the 0.71mm diameter unsheathed varnished stuff. The 0.5mm, whilst similar, had less bass and although that brighter balance often grabs the attention and one thinks initially it's better, it becomes fatiguing to listen to and a slightly warmer balance is always best to go with he says from a recording and mastering perspective. We thought neutral might be about 0.6mm diameter which is not available in small quantities.
I'd say it's not exactly the same as the original but with that particular test configuration it's the nearest, which is testing about 0.5 metre balanced.
I expect there is an error from the recording stage not sounding identical to the output stage, but it is a new state of the art DSD DAC ADC that cost £12,000 so it's not going to be too terrible. Monitoring has been through several loudspeakers but now it's mainly 'active' ATC SCM150's.
Then it come to other peoples playback equipment.....
And I find sometimes there's too little bass with this wire and I don't like the balance at all, although I and they very much like the clarity and amount of information and the lack or blur.