Hi Bryon,
Given your disciplined approach to things, a lot of the following has probably already occurred to you. But fwiw here is a list of conceivable extraneous variables that comes to mind, which I think need to be eliminated before the difference you perceived can be attributed to the pigtails with a reasonable degree of confidence.
Obviously, a way to eliminate most or all of these possibilities would be to go back and forth several times between having the pigtails in place and not having them in place.
1)Improved contact between the speaker terminals and the speaker cables, resulting from increased pressure and/or scraping away of oxidation that may have occurred during the loosening and re-tightening of the connections.
2)Changes in room temperature. Temperature is a parameter that is fundamental to the physics of transistors and other semiconductor devices.
3)Changes in AC line voltage.
4)Changes in AC line noise.
5)Changes in rfi/emi conditions, such as may be caused by wifi signals, cellphone traffic, nearby radio stations which may broadcast at different power levels during the day vs. at night, etc.
6)Ongoing aging, breakin, loss of breakin, or re-breakin of system components or the speakers.
7)Components being in a different state of warmup during the "before" and "after" parts of the comparison.
Undoubtedly there are other possible extraneous variables that I'm not thinking of.
Best,
-- Al
Given your disciplined approach to things, a lot of the following has probably already occurred to you. But fwiw here is a list of conceivable extraneous variables that comes to mind, which I think need to be eliminated before the difference you perceived can be attributed to the pigtails with a reasonable degree of confidence.
Obviously, a way to eliminate most or all of these possibilities would be to go back and forth several times between having the pigtails in place and not having them in place.
1)Improved contact between the speaker terminals and the speaker cables, resulting from increased pressure and/or scraping away of oxidation that may have occurred during the loosening and re-tightening of the connections.
2)Changes in room temperature. Temperature is a parameter that is fundamental to the physics of transistors and other semiconductor devices.
3)Changes in AC line voltage.
4)Changes in AC line noise.
5)Changes in rfi/emi conditions, such as may be caused by wifi signals, cellphone traffic, nearby radio stations which may broadcast at different power levels during the day vs. at night, etc.
6)Ongoing aging, breakin, loss of breakin, or re-breakin of system components or the speakers.
7)Components being in a different state of warmup during the "before" and "after" parts of the comparison.
Undoubtedly there are other possible extraneous variables that I'm not thinking of.
Best,
-- Al