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Mismatched Supply Rail Leads?
Mismatched Supply Rail Leads?
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Old 13th January 2020, 01:24 PM   #1
TrapJaw is offline TrapJaw
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Default Mismatched Supply Rail Leads?

Not sure if this question should be posted in “Solid State” or “Construction Tips”. Sorry if its in the wrong place. I’m presently rebuilding an old Adcom GFA-545 MKI amplifier. Upon reassembly, I cut the B- rail lead to short going to the PS. I lifted the board and replaced the existing 16 guage wire with 14 guage. After putting it back together, I wondered if the difference in wire sizes between the B- and B+ leads would cause an imbalance. The leads are only 2-4 inches long. Is this a concern. I guess I could fire it up (bad choice of words) and measure the difference. I don’t think it will make a significant difference. Theoretically I probably should replace all the leads the same 14 guage wire even on the other channel. Comments?
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Old 13th January 2020, 01:53 PM   #2
Mooly is offline Mooly  United Kingdom
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Mismatched Supply Rail Leads?
The simple answer is that it will make no practical difference at all.
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Old 13th January 2020, 08:15 PM   #3
PRR is offline PRR  United States
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Say you go to and from work on a dual-lane highway. And somehow both to and from are identical.

The town re-paves one side to be 0.001% smoother/faster. Is your to/from travel now unbalanced?

I don't think you can measure a difference (without fantastic equipment).

I think even #16 is WAY more than it needs for clean speech/music playing. The #16 may be designed for severe bench-testing loads. Or not really designed so much as "this feels OK".
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Old 13th January 2020, 09:36 PM   #4
Vovk Z is offline Vovk Z  Ukraine
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It dosen't really matters but if it disturbs I personally better make them equal to rest in calm (but 2-4 inches isn't long enough length to worry).

Last edited by Vovk Z; 13th January 2020 at 09:42 PM.
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Old 14th January 2020, 12:31 PM   #5
TrapJaw is offline TrapJaw
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Ok, dumb question. I just thought with people spending $1000s on low resistance power cables, it might make a difference. Thanks for the replies.
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Old 14th January 2020, 07:33 PM   #6
Mark Tillotson is online now Mark Tillotson
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The people spending that much on power cables are deluded, plain and simple. The different is economic, not technical!

In analog electronics rails are normally called V+ and V-, "B+" is purely a vacuum tube convention.
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