This was originally discussed in the "Novel" thread, but it seemed more appropriate to post some initial impressions here. Based on some posts by @Bricki and others, a couple weeks ago I added a 4th shield layer to my two Lush^2 cables, and I've been experimenting with various configurations since there. Some belated listening impressions (with thanks to @Bricki for the inspiration).
For the below, here is my labeling convention for the various shield configurations:
0 (Lush^2 Black wire - USB ground)
1 (Lush^2 White wire - inner shield)
2 (Lush^2 Yellow wire - middle shield)
3 (Lush^2 Red wire - outer shield)
4 (new wire - added outer shield)
Before adding the 4th shield layer, my Lush^2 configuration of choice was JSSG360^3 (A: 1-2-3 B: 1-2-3). Before that I was using JSSG360^2.5 (TANF) (A: 1-2, 3 B: 1-2-3) With standard Lush^2, I preferred the JSSG360^3 configuration: a bit darker and more relaxed, without a loss in detail.
I added braided shielding to both my Lush^2 cables, attached a solid core wire at both ends, and then insulted and wrapped the wires. Pro tip: if you use an appropriate gauge solid core wire, it slides nicely into the jumpers on the end, making it easy to experiment with the Lush^2 connection strip.
First, starting with the JSSG360x2 (A: 1-2, 3-4 B: 1-2, 3-4).
My initial impression of JSSG360x2 was very strong, and I preferred it to JSSG360^3. However, after some extended listening tests, I was finding the extra vividness to to be a bit too much on some more challenging tracks. That was motivation this weekend to step through some additional configurations to see what patterns I could see.
Alas, in a fit of unusual efficiency, I had added a 4th shield layer to both my Lush^2 cables at the same time (one from NUC 7i7 to IsoREGEN, and one from ISO Regen to Matrix Audio XSPDIF2, which then connects to my Hugo mScaler by Toslink). This meant I didn't have an easy way to compare the 4 shield configurations with the usual 3 shield Lush^2 configurations (DOH!) Below notes that compare to a standard Lush^2 are from memory, and should be consider a plea to someone with more foresight than me to test a 4 layer config against a standard 3 layer config.
JSSG360x2bullseye A: 1-4, 2-3 B: 1-4, 2-3
A JSSG360 pair nested between a JSSG360 pair. This definitely got my attention: Cleaner/darker sound, less high energy, more relaxed presentation. It retained the air and resolution of JSSG360x2, but cleaned up some of the fatigue I was sensing on some more challenging tracks. I preferred it to JSSG360x2. The new top dog.
JSSG360x2link A: 1-3, 2-4 B: 1-3, 2-4
Clean, but more high end energy than the bullseye config. Still seemed a bit better than 360x2, but still a bit fatiguing on the more challenging tracks. Bullseye still in the pole position.
JSSG360^3+ A: 1-2-3, 4 B: 1-2-3, 4
Same as my original favorite JSSG360^3, but with the 4th shield layer floating above it. Seems brighter than the 360^3 that I remembered, and more fatiguing. Not sure if leaving the 4th layer floating is a wise thing to do. I still prefer bullseye.
JSSG360^3.5 A: 1-2-3, 4 B: 1-2-3-4
Cools things down a bit, and takes away some strain, but still brighter than I remember with JSSG360^3 before adding the 4th layer. Still prefer bullseye.
JSSG360^4 A: 1-2-3-4 B: 1-2-3-4
Better, but still seems brighter than I remember the JSSG360^3 (and yes, at this point I'm kicking myself for not leaving one Lush^2 cable with the standard 3 layers) Makes me want to go back to Bullseye.
So based on above, I went back and reread some of the original JSSG360 posts and discussion. In all the above configs, the USB ground line (Black on the Lush^2) was disconnected, meaning the shield layers were floating from the source and destination. What would happen if I started bringing USB ground back to the party?
JSSG360+360^3 A: 0-1, 2-3-4 B: 0-1, 2-3-4
This config connects USB ground from source to destination but leaves the 360^3 layers still floating. Still too much brightness for me.
JSSG360x2s A: 0-1-2, 3-4 B: 0-1-2, 3-4 (favorite)
So what happens if the inner JSSG360 pair is connected to USB ground on both sides, and the 2nd JSSG360 pair is floating? This is a winner! Great detail, less harshness than 360x2 with the more challenging tracks. This is currently my new favorite.
JSSG360x2s1 A: 0-1-2, 3-4 B: 1-2, 3-4
JSSG360x2s1’ A: 1-2, 3-4 B: 0-1-2, 3-4
So what about floating USB ground on one side or the other? Still keeps the great air and detail of the 360x2s, but is a bit harsher on more challenging tracks.
JSSG360x2bullseyeS A: 0-1-4, 2-3 B: 0-1-4, 2-3
So how about adding a USB ground connection to bullseye? Would that bring it even with 360x2s? Not quite. Definitely cleaner and with less high end energy than bullseye, but I am finding myself wanting to go back to 360x2s
With the initial survey done, time for some extended listening with JSSG360x2s. With that new baseline, I may be tempted remove the 4th shield layer on one of my Lush^2's, and directly compare JSSG360^3 to JSSG360x2s.
Empirical listening aside, I'm still trying to get my head wrapped around the field dynamics in play when you have this many shield layers. Given that I still don't have a hypothesis for why JSSG360^3 would be better than JSSG360, the complexity of having a 4th layer makes it even harder to understand why one config sounds different than another. When are layers an antenna and when are they a Faraday cage? In aJSSG360 config, aren't they both at the same time? I need to ponder this some more, with something stronger than sparkling water.