According to JohnYang1997, practical (short term?) Is about 8A.
The AC adapter official specification 4A may be a continuous output guarantee value including strict conditions such as industrial use. Especially the temperature.
Of course, I think it is better to avoid continuous output for several hours at 4A or higher.
Perhaps the temperature of the amplifier will be the first limit.
@JohnYang1997 Is it OK for a customer to use a different power supply? Is there a performance gain (dynamic power at 6ohms or 4 ohms) using something like this? https://www.amazon.com/NES-350-36-Switching-Power-Supply-110-240/dp/B01AWQ0Y52 No. And no.
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