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AU-999 Overhaul Oddity on Preamp Boards

N

Nati Dread

New Member
I have gotten through the recommended recaps (well, electrolytics only) and started on the resistors. When I went to add the 1 meg resistor there was already a little 47pF cap in the exact location where the 1M resistor was supposed to go. Someone had long ago pulled the subsonics and crowbars because I've had this thing for decades. Presume that I should remove it and replace with the resistor, but wondering if there was a previous mod to these AU-999s that I need to be aware of.IMG_20220228_164110384.jpg
 
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Nati Dread said:
I have gotten through the recommended recaps (well, electrolytics only) and started on the resistors. When I went to add the 1 meg resistor there was already a little 47pF cap in the exact location where the 1M resistor was supposed to go. Someone had long ago pulled the subsonics and crowbars because I've had this thing for decades. Presume that I should remove it and replace with the resistor, but wondering if there was a previous mod to these AU-999s that I need to be aware of.View attachment 2499118
Click to expand...

Can you get a better picture of the board to see what else around it? It is too close.
 
Sorry to be dense, but I leave them and put the 1M resistor there as well? Or is removal recommended for this preamp mod?
 
My first recap (AU-999) is up and running and sounding pretty good with tons of bass after the AudioKarma mods. I am having an issue with setting bias and current in that the vales are constantly varying, does this mean I still have issues or am I doing something wrong? I put together a massive load resistor of about 8 ohms.
 
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