Shielding high voltage wire
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beasleybodyshop
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Shielding high voltage wire
Any disadvantage to coiling wire to ground around the HV coming off the power supply to the preamp? Or is this a waste of time? I see on early silverface fender amps they do this to wires coming out of the dog house to the preamp.
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Leo_Gnardo
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Re: Shielding high voltage wire
For those who need a super low noise floor, yes a shield around the HV is good. What works even better for me is grounded copper foil or sheet behind the norm channel volume, treble & bass controls. If a little hum doesn't bother you, then don't bother.
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beasleybodyshop
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Re: Shielding high voltage wire
So your trying to prevent RF from right after the first gain stage?Leo_Gnardo wrote:For those who need a super low noise floor, yes a shield around the HV is good. What works even better for me is grounded copper foil or sheet behind the norm channel volume, treble & bass controls. If a little hum doesn't bother you, then don't bother.
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Stevem
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Re: Shielding high voltage wire
The gain stages where the audio signal is the smallest is where the most improvement will be had by wire layout.
Old Gibson amps use to have braided shielding on the OT primary wires due to the long run that they made from almost one end of the chassis to the other!
Old Gibson amps use to have braided shielding on the OT primary wires due to the long run that they made from almost one end of the chassis to the other!
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Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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Leo_Gnardo
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Re: Shielding high voltage wire
Mostly 120 Hz hum here, not RF. It only seems to bother old jazz players (30 to 80 y/o) that detest hum.beasleybodyshop wrote:So your trying to prevent RF from right after the first gain stage?Leo_Gnardo wrote:For those who need a super low noise floor, yes a shield around the HV is good. What works even better for me is grounded copper foil or sheet behind the norm channel volume, treble & bass controls. If a little hum doesn't bother you, then don't bother.
down technical blind alleys . . .
Re: Shielding high voltage wire
I've seen shielded HT wires in a Fargen Miniplex. In that amp, I assumed that it was due to the fact that SE amps pick up extra noise and because the amp is often used as a recording amp.
That being said, I recently did a SE amp with a similar power section and I didn't shield the HT. My build didn't have much noise to speak of. In one of my builds, I used 1/8" sheet aluminum (bent like an L) to form a grounded shield between the power section and control panel - it worked great to eliminate a hum that was bugging me.
That being said, I recently did a SE amp with a similar power section and I didn't shield the HT. My build didn't have much noise to speak of. In one of my builds, I used 1/8" sheet aluminum (bent like an L) to form a grounded shield between the power section and control panel - it worked great to eliminate a hum that was bugging me.