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by kd913 525 days ago
I think there can be a difference here.

Was looking recently at the power requirements of an amp + subwoofer + 5 5.1 JBL surround speakers.

The setup was done decade ago, and the power needed for it was nuts. Something like 500W for a Denon amp and 250W for a JBL subwoofer?

For reference something like a OG HomePod consumes what 45W? The Sony srs xg500 boombox can last 30hours and is a giant room shaking boombox.

The difference in power efficiency between these old and new setups are nuts. Nevermind compatibility with AirPlay, streaming etc…

4 comments

> 500W

Amplifiers are quoted in peak output, not average (and play some games with other parameters e.g. resistance) to capture bigger-number-better sales. A 750w system will consume nowhere near 750w at typical listening volumes (just like your 750w PC doesn't use 18 kWh every day.)

Unless you’re playing REALLY loud, I don’t think you are anywhere near 250 or 500W of consumption. I would guess it is the maximum rated power?

Even with quite old and inefficient amp + speaker combo, 30W of sound is usually a lot(!).

Tube amps are an exception. They can be very power hungry, but it’s difficult to buy such tech today compared to class D etc.

There's also an absolutely massive difference in audio quality between a HomePod or Sonos anything and a proper amp + speakers.
Yup. Newer products use various tricks to try to fill in the gaps that their physical reality can't overcome, but ultimately there's no getting around that reality.

I will say that the Sony upright boom boxes aren't to be slept on (and, if one is active, fat chance). They're quite good for their intended use cases (parties, and closed Best Buys during clean-up/inventory).

A 500W amp is probably a class A and can't really be made more efficient. It would still be 500W in 2024. Decades ago there were more efficient setups too, though of course now they sound better and also have lots more features and connectivity.