Direct input and direct output

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Could you please lecture me on Direct Input and Direct Output?

The manual says that the Normal output should be used for amplifiers that you are not sure can protect your speakers from DC in the signal path.

Not sure what the Direct Input does. is added/removed from the audio path?

Both are recommended for best fidelity sound.

Answers

  • cortico
    cortico Posts: 587
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    I got my question clarified, makes sense :

    Direct output stands for direct coupled, or no capacitors in the audio path. The normal output probably uses a capacitor in line with the output to keep any DC offset at bay. Same with the normal input on the amplifier. If you use Direct for both output and input, it should bypass this filtering"
  • mhardy6647
    mhardy6647 Posts: 33,027
    edited April 2019
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    As long as there is no stray DC anywhere in your signal path, you'll be fine. If there is any (e.g., signal from a source riding on a DC offset, or a balance issue in pre- or power amp), any amplified DC that present at the power amp outputs will cook your loudspeakers.
    If the voltage is high enough it could happen instantly and soundlessly*.

    Pretty simple B)

    BTW, transformers can be used instead of capacitors for coupling and/or isolation, often to better effect than capacitors... but at a much higher expense (for good, wide-bandwidth iron) :)

    The great sounding pro audio consoles of yore used transformer coupling.

    ________________
    * Don't ask me how I know this. :p
  • cortico
    cortico Posts: 587
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    haha, I yet to fry a speaker. But have cooked a couple of amp channels.
    I am aware of transformer couple outputs, there are a few 70's receivers that have this scheme.

    Interestingly I always liked capacitor couple output amps, and I do prefer the preamp sound when not using Direct input/output... it's a bit smoother