Relay contact rating

But, the relay rating is for DC or 50/60 Hz AC power supplies, and the audio signal is broadband AC. That means many harmonics might add to make transient peaks far beyond any reasonable ratings.

A 5x 'crest factor' is commonly applied to audio AC, and that means a 1A average current is handled by >5A transistors in an amplifier. The transistors can fail in a millisecond or so with overstress.

The relay is not going to be repeatably switching peak currents, it's going to have a few transient peaks while completely open or completely closed. So, 1A of heat-producing current is associated with 5A peaks, AND THE RELAY ONLY CARES ABOUT THE 1A number. The relay will take seconds, not milliseconds, to fail with overcurrent.

"John Fields = TROLL"

Compressed rock/pop music has similar characteristics to ( audio band limited) pink noise, which has a crest factor of about 13dB.

It represents a typical, worst case scenario for a domestic amplifier.

F*ck head.

.... Phil

"John Fields = TROLL "

DC.

oor

I believe the correct term is crest factor, dynamic range is something entirely different

-Lasse

I believe the correct term is crest factor, dynamic range is something entirely different

Dynamic range of music programme refers to the difference ( in dBs ) between the loudest and softest passages in a piece of music.

Highly compressed pop music has a very narrow dynamic rage ( maybe only 3 dB ) and closely resembles band limited pink noise in most other respects.

The crest factor of pink noise is about 13 dB, unless there has been some deliberate tampering to get the figure lower - eg heavily clipping the peaks brings it down to 6 dB.

.... Phil

use

or DC.

poor

I did not say it would not work. I said that life would be poor. Big difference.

?-)

I remember this being demonstrated in the earley seventies at the BBC using 'Telstar'by the Tornados. The PPM needle barely moved.

Cheers

.... Phil