It is certainly possible that the standards body got it wrong too. The individual responsible who thought that RMS might be a good name for something which has nothing to do with RMS could also not realise the difference between power and average power.Charles Darwin said:
I do. Of course.Pano said:
You seem to finally have got it but was it really necessary to try to shoot the messenger twice using sinuous strawmen?
That said I very much doubt that it was an individual who was responsible.
One can pretty much guarantee that it was a committee drawn from representatives of all 15 EU nations at the time.
Nope. As yet said in posting #14, the German term the Deutsche Institut für Normung (which the abbreviation DIN correctly stands for) used in DIN 45500 was Sinusleistung, not RMS power. Sinusleistung was defined as the maximum power at a maximum THD level of 1% that an amplifier was able to deliver continuously over ten minutes when driven by a sine Signal, without getting too hot or being destroyed.
Best regards!
I took the definition from DIN EN61305 which the site claimed evolved from DIN45 500.
Either way there has been an EU wide and presumably legally binding definition of RMS power since 1996. What I thought was missing was a crest factor for the pink noise used.
In the end I just searched wrms and found the seemingly appropriate norm.
I did not look up 45 500 specifically, mostly because it has been out of date for 20 years and was only applicable to Germany.
Either way there has been an EU wide and presumably legally binding definition of RMS power since 1996. What I thought was missing was a crest factor for the pink noise used.
In the end I just searched wrms and found the seemingly appropriate norm.
I did not look up 45 500 specifically, mostly because it has been out of date for 20 years and was only applicable to Germany.
I'm not sure what it is I am supposed to have "got". I asked whether your statement used 'maximum' in its normal sense or really meant 'maximum average'; whether you were quoting someone else or speaking on your own behalf was unclear but in either case you could have said what you meant or understood them to mean, as appropriate, or said that you were merely the messenger. I am not aware that I shot anyone.Charles Darwin said:
Several years ago I had a double cassette player/recorder (Sanyo) that performed few years until I started my DIY project actually using. It said "120W PMPO". Wow! Strangely, once I disassemble to clean the pots (Noisier) and the speakers was only 4W RMS. Very ridiculous, no? The power trafo was 5*5*5cms. "Such a power density, I thought".
"A camel is a horse designed by a committee"
Crest factor in recordings was ever changing, due to loudness war.
Yes it was decreasing, partly because spread of pop and techno music, where nearly constant high acoustical level is an attribute of music. But there is another reason: our environment got noisier, so music has to stand out of the background. Think about traffic noise, aircrafts, AC, computer fans, crowd chatting in the disco, listening music by earbuds on the metro, etc.
Not sure I see it.
I mean if I have a certain BOM cost target I can build a 5W amp that clips at 5W into 4 ohms, or a 2.5W amp that clips at 25W into 4 ohms, for music, one of these is going to be a lot better then the other and it is not going to be the 5W one...
Of course the single number marketing guff never catches this sort of thing well.
Reducing the heatsinks and spending the money instead on higher supply rails and more peak current is for an AUDIO AMP pretty much always a win over designing for clipping at 100% DF sine.
This changes of course if you are trying to drive shaker tables, but that hardly counts.
Engineering is a trade off (always), make the ones that optimise for the problem you actually have.
Regards, Dan.
When sphincters are ready to unleash, and you have goose bumps hearing musicians and singers here and now, but not seeing them.
Of course the end result is subjective, but from objective point of view, most audible distortions have to be minimised first, instead of going for some "standard measurements" of distortions that do not matter. It is not hard today to get low THD level; what is hard, to understand how dynamic distortions affect the sound, and concentrate on how the amp and speakers misbehave, instead of paying attention to so called "linear region" that was never a problem for well designed equipment.
In the context of recent posts, it might be defined as good audio reproduction of sounds/music with high crest factor.
Then there's the (quoting another poster) "mass production HiFi" or what some might call mid-fi, playing modern pop music with hypercompression that has lowered the crest factor asymptotically towards 1.
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