NAD: Mesa Boogie Mark VII head. WOW

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Unfortunate, that minor change went back to worse, near deaf. All thanks to blocked Eustachian tubes and trapped fluid in the inner ear. Last resort is to have glass tubes inserted in the ear drums. No plan on doing that just yet.
 
Hey, anyone removing their Reissue IIC+ Chassis out of the head shell, there is one thing you need to be aware of. (I did not take this picture, I borrowed it as I have not uploaded my pictures yet).

In the upper left area just below the large toggle switches (the cap just below that between the standby and GEQ switch) Look at the one capacitor with the green insulator on it. That needs to be there when you go to put the chassis back into the head shell. Since the cap is probably in series with the one next to it, the metal canister of the capacitor is connected to the -terminal, not at ground potential but half the plate voltage. If that insulator is missing, the power supply could arc or may even touch the foil on the head shell. I do not believe it makes direct contact. The insulator is more than likely required by UL for proper creepage clearance to the foil shield that makes contact with the chassis when it is installed.

5487-IMG-7406.jpeg


Also figured out where the hum was coming from. V1. Found that if the bass shift was pushed in, the hum was much louder and would go away when pulled out. I assume that all of the preamp tube heaters are AC sourced.
 

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