Hifonics Thor XX

What is an acceptable level for this amplifier? I've heard 250mv I've heard 500mv dc. I want to reduce it as much as possible.

I have the amp up and running and load tested but I'm reading -.388v DC on the speaker terminals with no load.

-.356v DC with a 2ohm load so it drops slightly.


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Acceptable to whom? Some techs won't let an amp go out with more than 25mv.

500mv certainly isn't going to do any harm. Is there an audible pop when the output stage engages?

Does the amp have a noticeable increase in current draw when you connect a load?

The problem (if it's deemed to be one) is likely the TL072 on the driver board. This assumes that the op-amp driving the signal to the driver board doesn't have so much DC on its output that it's leaking through the blocking capacitor between the op-amp and the driver board.
You have to consider various things.

Some tech can charge $100/hour and have customers who will pay it to get the DC offset (or other minor issues) to 25mv if the tech tells them that's what's 'right'.

Some people just want their bass amp back. They are absolutely lost without them and are not going to spend one penny more than absolutely necessary to get their bass back.

Most are in-between. You have to look at the situation and make the executive decisions for your business.