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I am making an amplifier that requires speakers with an impedance of 8 ohms but I have 6 ohm speakers. I have made this circuit before and it worked with my 6 ohms but now I'm more wondering that is all means and how does the impedance tie into an amplifier?

Also while I'm on the topic of my amplifier, it requires 12 volts DC and I want to build a circuit that converts AC to DC from  my wall.
Now , I know how to transform it and rectify it and filter it BUT my question is just what value filter capacitor would I need for this amplifier?

It uses 2 TDA2005 amps and it outputs 20 Watts per channel (2 amps per channel, if you didnt know already).

Lastly,  the earth connection of the plug should be attached to the metal enclosure of the amplifier once I make it right?
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I am making an amplifier that requires speakers with an impedance of 8 ohms but I have 6 ohm speakers. I have made this circuit before and it worked with my 6 ohms but now I'm more wondering that is all means and how does the impedance tie into an amplifier?

Quote
Should still work OK, just keep the volume below max current level of amp by keeps volume only as loud as really needed.

Also while I'm on the topic of my amplifier, it requires 12 volts DC and I want to build a circuit that converts AC to DC from  my wall.
Now , I know how to transform it and rectify it and filter it BUT my question is just what value filter capacitor would I need for this amplifier?

My old rule of thumb for 12vdc power filters caps was 1,000 mfd per amp of current rating, so if you size the transformer for 2 channel X 2 amps = 4 amps then 4,000 mfd should be fine.
Or is that 2 amps  2 channel X 2amps each = 8 amps then 8,000 mfd, you figure it out.  smiley-grin

 



It uses 2 TDA2005 amps and it outputs 20 Watts per channel (2 amps per channel, if you didnt know already).

Lastly,  the earth connection of the plug should be attached to the metal enclosure of the amplifier once I make it right?

That's standard code for three wire power plugs. But keep in mind most stereo amps built in the 70s (a classic era) used 2 wire power cords, so there was no grounding of the case to AC ground at all, so It's a safety issue, not a functional requirement.

Lefty
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