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Checking DC offset on NAD 7125....

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Domsmith1970

Member
Hi guys. I have a NAD 7125. Have previously posted about a pop when powering it up. Have also noticed the right channel runs a bit weak/distorted. I love to learn so I am going to check the DC offset. I have the schematics...and you can adjusted everything. Now...the schematic manual has a section entitled "Alignment method"...is this the same as DC offset? I have read the "sticky" for "DC offset and you" and the "Alignment Method" seems similar. It says to test the speaker outputs for center voltage, which I understand. Adjust between 0-30mv. But it also states states to check idling current. How do I do this with the power off? It says to leave the power on for 5mins after adjusting...sounds like the power has to be on when checking idling current.? It also states to check the output transistor's emitter resistor....can't seem to locate this. I am very new to this and am a bit nervous. At the very least I feel confident to adjust the center voltage, but the idling current makes me nervous.
 
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Center voltage, dc offset are the same thing. Alignment is setting the offset and bias (idle current). For offset, the measurement is across the speaker terminals. For bias, the measurement is across the emitter resistor indicated in the service manual. All adjustments should be made with the power on, no signal and no loads (speakers).
 
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