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Some amplifiers have used relays to "turn on" the speakers. This is done to prevent the popping sound on the startup of the system and the speaker.

When using my previous TDA2050, is it not a better option to pull the non-inverting input (pin 1) to ground on "startup" and then "gradually" apply the midpoint bias voltage via R1 after a few seconds?

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If we had +Vs to be 24V.

Yes, I understand you will still get a spike on the output, but it will be amplifying the input offset voltage which is not that large when compared to having the mid-point bias amplified (which in most cases will touch the positive rail).

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  • \$\begingroup\$ You're likely to get a "pop" regardless, as +Vs rises quickly, depending on TDA2050 internal bias methods. The relay method is quite robust, but expensive. \$\endgroup\$
    – glen_geek
    Commented Sep 10 at 16:48

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The R1 and C2 already do that.

The time constant is 1.1 seconds. It can be considered to be fully charged in 5 time constants or 5.5 seconds.

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  • \$\begingroup\$ @DaveTweed Thanks, fixed already. \$\endgroup\$
    – Justme
    Commented Sep 11 at 15:56

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