Just did a video/pictorial on this. Link below...
This debate or urban legend always seems to creep up among the Sovereign/Excalibur crowd from time to time. I've been guilty of speculating about it myself in the past and gone back and forth on the potential benefits it might have. So I did a video with some depth comparisons precisely measured with and without a much longer coil cable involved, because I've heard some say in the past that they had the impression after shortening the excessive extra long cable length (meant for hip or chest mounting the Sovereign or Excalibur for land or water hunting) they thought it might have enhanced depth or performance for them.
I wanted to see for myself if there is any evidence for that, because perceptions can be a tricky thing unless you nail down the variables to contrast any differences that might exist (if any) in as precise a manner as possible.
It's also been speculated and kicked around here and there from time to time that not using the meter or using one with it's own power source (some meters for the Sovereign have their own battery) would increase depth due to some meter's that draw on the TX output to the coil to derive their power. In reality the meter is wired in parallel to the coil, so the coil still sees the same level of source voltage regardless of whether the meter is plugged in or not. The power draw of these meters is minuscule anyway, but just the same I wanted to test that as well.
This video might finally have some solid answers as to if there is any evidence to support either of these things one way or the other. At least on the BBS units perhaps in terms of longer coil cables, since they are somewhat unique among detectors because of the pre-amp in the coil where a longer coil cable might not be as much of a issue thanks to the more "robust" signal" signal being sent back to the control box. This is what Minelab says about the pre-amp in the BBS machines.....
In-Coil Signal Booster
RCB (Receive Coil Boost) circuitry greatly amplifies weak target signals, from small and deep targets, inside the search coil, where the signals are received. This has three main advantages over standard techniques of amplification inside the control box:
1.Greater immunity to electrical noise, reducing false signals
2.No loss of signal strength, and faint targets, through the cable
3.Improved detection depth and sensitivityHere's the pictorial/video I did, and keep in mind I'm "inflicting" and then removing both "burdens" on the machine at the same time for comparison (longer coil cable and meter drawing from the TX output), so if there was to be any potential small measurable benefit from either, we should see that here.....
http://youtu.be/1CRxPoJ6O7oBut yea, the way I look at things is if it can't hurt and might help, like shortening the cable, then what's the harm of rubbing that rabbit's foot?
I'm so particular about things that I run the coil cable straight up the shaft to get it as far away from the coil as fast as possible, and even flip the snap head shaft adjustment pin upside down so the bottom of the "V" is pointing away from the coil. Way I look at it if it can't hurt then what's the harm of being a little "superstitious"? Who knows, a bunch of little things with zero impact by themselves, might end up adding up to something that can have measurable results in the right rare situation? I even put several extra velcro loops on the shaft to secure the cable, so as to insure it won't move in some small way and be seen by the coil.
Think I'm finally home after a lot of years searching for my particular needs. Custom 1.5 lb lighter 
Sovereign GT (easy to do by just "building" lighter shaft) & SEF 12x10 as everyday coil. 8" Tornado (actually 7.25") as super heavy trash coil (Very deep & separates better than typical 8/9" true size coils). 13" Ultimate for large fields/beaches on certain days I want to grid faster than even the 12x10's nice improvement over stock for that. Stock 10" Tornado stays on water rig (stock shaft). 
ProPointer. Owned 15x12 & SunRay S-5 (5.5") at one time. Loaned a prior 13" Ultimate & SunRay S-12 (12.5").
Some Oldest Silver- 1835 Bust Dime, 1842 "O" Seated Dime, 1855 Seated Quarter, 1858 3 Cent Piece, 1891 Seated Dime, & another Seated Quarter too damaged to read date. Highest Value- 3 Cent Piece, Seated Quarter, & now 1921 F-12 Standing Liberty. Oldest Coin? Got to give large cents a good look & see. 2013 so far- 1 Seated Quarter, 1 Barber Quarter, 1 Standing Liberty, 2 Washingtons, 1 Barber Dime, 9 Mercs, 3 Rosies. 1 War Nickel. 19 silvers in total, & 1 1872 key date Indian, 2 Bufallos, 1 man's 14K gold medium sized ring & 1 gold chain, with possibility of few 8"+ deep mystery coins being Indians after cleaning.
What matters in life is the journey and not the desitination. How you handle that journey determines if you were a success, not so much what you achieved if and when you finally get there, especially if you made it by stepping on people along the way...
In loving memory of my long haired (wooly) husky Sky. She taught me just how beautiful and pure a soul can be, human or not...Edited 5 time(s). Last edit at 01/31/2013 01:24PM by Critterhunter.
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