Threshold Amplifier - Overview and Schematic Collection of all Models

Official Court Jester
Joined 2003
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change something in signal wiring , or change something in mains cables - find a way to break safety earth for , say, monos

use either cables without safety earth wire , or T adapters without the same

be aware that you can use that trick only when everything is connecetd , so amps without safety gnd connected through mains cables are effectively having safety gnd through signal cables

pretty much normal thing in PA gear , most amps having switch on back side for several arrangements of safety gnd
 

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The one and only
Joined 2001
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When you start multi-amping, noise generated by ground loops starts to
rear its ugly head. Most often the loop is in the AC Earth connection, so
that is a good place to start. I usually isolate the AC Earth on various
pieces to see how it affects the noise and proceed on that information.
 
Hallo Mr. Pass,

thanks for your response. I‘m not sure about the wording, is this platelelet (metallstrip can be seen in the front of the picture, the ac earth (or ground)?

Hope the upload works
 

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this is question for Pass himself ..... I don't have any schematic for T400

as far as I can see , T400 is made 1998 , while Pa left Treshold year before ....

so - that's probably why I don't have schematic

edit: yeah , as usual , while I was typing ...... :)
maybe on the former condition of the pages the wanted schematic is present as pdf file (checking out needs time unfortunately):
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Thank you, I try first with some isolating material between plug and socket earth wire of the amps. I'll keep you informed
any news?
 
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Member
Joined 2013
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Here is what I have, don't know if this helps or not. I don't know if the FEB is the same for preamps and amps. I have a FET 10 Pe, and I have collected schematics over the years of ownership, including the original owners manual which shows the DIP switch settings for the "e" model.
 

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