[Amps] Article about RMS Power????

[Jim Brown]

Because audio is wildly dynamic, discussions about power and signal 
levels can get confusing. Audio program material is virtually never 
close to approaching sinusoidal. The practical limitations include the 
"beefiness" of the power supply, and voltage and current capabilities of 
the output devices, and dissipation. In addition, audio power amps are 
constant voltage devices, with output impedances generally below 0.1 
ohms. If their power supply is sufficiently beefy, the power they can 
provide is inversely proportional to the load impedance. Not only that, 
the load impedance of real loudspeakers is a highly variable complex 
function, including various electrical and mechanical resonances in both 
the transducers and their enclosure. Loudspeaker impedance is defined as 
the minimum value of the magnitude of the impedance in the midrange; in 
multii-way loudspeakers, there's also a passive crossover network that 
distributes power by frequency range between two or more drivers, and 
adjusts the relative levels to each frequency range depending on the 
sensitivity of the transducer for that range.

So-called RMS power ratings for power amps are for a constant sine wave; 
mfrs of amps with less robust power supplies often use "music power," 
which the based on the RMS value of a sine wave corresponding to the 
audio peaks in program material. This is not an unreasonable cheat, 
simply because all audio is so dynamically variable.

73, Jim K9YC

  On 1/20/2020 12:15 PM, Fuqua, William wrote:
>     There is an article about RMS Power in Electronic Design. Naturally it has to do with High Fidelity stuff.
> What they are referring to is Continuous Average Power but calling it RMS Power.
> 
> https://www.electronicdesign.com/power-management/article/21120866/whats-the-difference-between-rms-and-peak-watts?utm_source=EG+ED+Analog+%26+Power+Source&utm_medium=email&utm_campaign=CPS200117061&o_eid=7152E2758401H1B&rdx.ident%5Bpull%5D=omeda%7C7152E2758401H1B&oly_enc_id=7152E2758401H1B
> 
> I was going refer to author as an HF nut but that would be confusing. High Frequency RF or High Fidelity? Hi Hi
> 
> 73
> Bill WA4LAV
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