Hi all,
does anyone knows a system which can test the AES Power? I mean professional equipment with testing protocol🙂 Any information would be appreciated. Thanks!
does anyone knows a system which can test the AES Power? I mean professional equipment with testing protocol🙂 Any information would be appreciated. Thanks!
Uhm, what exactly do you mean? AES (and I assume /EBU) is a digital format - power has little to do with it.
AES is a big place.
In the 1970s, ElectroVoice was rating their professional speakers by an AES standard (which I had the idea originated at E-V and was ratified through AES). It uses pink noise through a filter which takes the extreme bass and treble down, supposedly an approximation to the spectrum of an over-driven guitar, which may be about worst-case. There are specs for the RMS of this hiss, and the headroom of the amplifier (some clipping is allowed). There's a number of hours the speaker must survive, though I do not know if AES picked this or the manufacturer.
Speaker power has two limits. It may melt. It may slap. The shaped pink hiss tests both. E-V had some astonishing numbers, like 600 Watts on a 2-inch coil. Of course by the nature of random noise this may be 150W of just heat. But the random peaks will also slam the mechanicals pretty hard.
I have seen that spec in full but not in decades. I'd think you start there. Pink hiss is easy and I recall a simple passive filter to shape it. Power amp is just Watts and Watts are cheaper than ever. You have a clock. I don't recall if the speaker must afterward be tested for small change of performance, or just be "functional", or may be a smoking ruin?
In the 1970s, ElectroVoice was rating their professional speakers by an AES standard (which I had the idea originated at E-V and was ratified through AES). It uses pink noise through a filter which takes the extreme bass and treble down, supposedly an approximation to the spectrum of an over-driven guitar, which may be about worst-case. There are specs for the RMS of this hiss, and the headroom of the amplifier (some clipping is allowed). There's a number of hours the speaker must survive, though I do not know if AES picked this or the manufacturer.
Speaker power has two limits. It may melt. It may slap. The shaped pink hiss tests both. E-V had some astonishing numbers, like 600 Watts on a 2-inch coil. Of course by the nature of random noise this may be 150W of just heat. But the random peaks will also slam the mechanicals pretty hard.
I have seen that spec in full but not in decades. I'd think you start there. Pink hiss is easy and I recall a simple passive filter to shape it. Power amp is just Watts and Watts are cheaper than ever. You have a clock. I don't recall if the speaker must afterward be tested for small change of performance, or just be "functional", or may be a smoking ruin?
OK, while the AES spec is copyright, not distributed for free, I came across a Russian site with what appears to be a valid copy of the 1984 spec.
http://diy-audio.narod.ru/litr/AES2-1984-r2003.pdf
This does not specify E-V's guitar-shaped noise, but a simpler shape. (May not be a large difference in practice.) There are specs for RMS and for clipping. The speaker must not only survive, but be OK afterward.
"The rated power of the device shall be that power the device can withstand for 2 h without permanent change in acoustical, mechanical, or electrical characteristics greater than 10%."
JBL has a user-level overview which says about the same thing, but adds interpretation.
https://www.jblpro.com/pub/technote/spkpwfaq.pdf
This cites IEC Standard 268-5 and says 8 hours.
http://diy-audio.narod.ru/litr/AES2-1984-r2003.pdf
This does not specify E-V's guitar-shaped noise, but a simpler shape. (May not be a large difference in practice.) There are specs for RMS and for clipping. The speaker must not only survive, but be OK afterward.
"The rated power of the device shall be that power the device can withstand for 2 h without permanent change in acoustical, mechanical, or electrical characteristics greater than 10%."
JBL has a user-level overview which says about the same thing, but adds interpretation.
https://www.jblpro.com/pub/technote/spkpwfaq.pdf
This cites IEC Standard 268-5 and says 8 hours.
This page suggests that AES 1984 has been changed to AES 2012.
And that IEC 1978 specified 100 Hours (more than the 1972 spec).
EIA also put out a test spec. The 1998 spec is so comprehensive that nobody does it.
As for "a system", the setup is simple and is only run on new designs. I'm sure almost everybody just runs the tests by hand.
And that IEC 1978 specified 100 Hours (more than the 1972 spec).
EIA also put out a test spec. The 1998 spec is so comprehensive that nobody does it.
As for "a system", the setup is simple and is only run on new designs. I'm sure almost everybody just runs the tests by hand.
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