Power consumption

[mkfs9]

Hi We always wondered how much power our peavey CS4080 drew from the mains,so we plugged in a device that measures the draw. To our supprise it was 0nly about 400 watts . This does not seem possible. we were running two qw4 cabs full range with fully miked band.Just to check the device we plugged our kettle in and it instantly went to 2900 watts.

[abbotsmike]

Depends on the type of program material, where the gains were set, and what the input level was. Was the amp just at the level of clipping? or way below that?

You also have to take into account the crest factor of music, as although it may peak at full power, the average value will be way below that, unless you are playing sine waves all night.

[mkfs9]

Depends on the type of program material, where the gains were set, and what the input level was. Was the amp just at the level of clipping? or way below that?

You also have to take into account the crest factor of music, as although it may peak at full power, the average value will be way below that, unless you are playing sine waves all night.

 

 

The amp was running full power and desk was fairly high. Not clipping amp but pretty loud. and a big bass drum.

[smalljoshua]

That's still usual for a power amplifier.

 

You'd basically have to be playing pink noise at full volume through the system to get the amp anywhere near full power.

 

Josh

[matt-the-dj]

not unusual,

had a 9.6k rig running at full levels at about 6 amps. the loads are very transient so quite low, the kettle is either 100% or none. Its one of the reasons why power showers have between 6mm and 10mm feeds all or nothing. 100% of a 9.6kw load is somewhere near 40 amps.

[Jivemaster]

I suspect that there are numerous 4 - 10 K amp racks that have run satisfactorily off a 13a feed. Typically a working PA amp draws about 1/8 to 1/4 of it's rated power due to the nature of the music input. However they may need switching on in sequence.

[themadhippy]

I suspect that there are numerous 4 - 10 K amp racks that have run satisfactorily off a 13a feed.

I much more prefer a 6A supply for running 4 Lab Gruppen FP 10000's and associated pa kit plus the backline

[mackerr]

I suspect that there are numerous 4 - 10 K amp racks that have run satisfactorily off a 13a feed.

I much more prefer a 6A supply for running 4 Lab Gruppen FP 10000's and associated pa kit plus the backline

 

If all the wiring is also 6A rated you may be starving your amps. It is true you may not blow the breaker because you don't exceed the time constant at a high enough power draw, but the instantaneous draw can be quite high. You can't usually meter those peaks unless you have a peak reading volt meter that has peak hold capability, just as it is difficult to know what your peak audio levels are without peak hold.

 

There is no such thing as a power source that is too big.

 

Mac

[KidRay]

I much more prefer a 6A supply for running 4 Lab Gruppen FP 10000's and associated pa kit plus the backline

 

I think that was a typo.

 

He may be a Mad Hippy, but I don't think he's that mad :)

[themadhippy]

nope no typo,full pa ,4 monitor mixes and a sex pistols tribute all running off a 6A breaker,it did finally trip,half way through the support bands sound check,that's when we discovered what the stage sockets were fed from.

[Samwise]

http://i282.photobucket.com/albums/kk255/samcampbelllighting/Safari.png

 

This is taken from d&b audiotechnik's manual for the D12 amplifier. I think I'm in love with this company. Is that weird?

[KidRay]

nope no typo,full pa ,4 monitor mixes and a sex pistols tribute all running off a 6A breaker,it did finally trip,half way through the support bands sound check,that's when we discovered what the stage sockets were fed from.

 

Ah, I see. You are that mad.

 

I stand corrected. :)

[Stan Hope-Streeter]

I think I'm in love with this company. Is that weird?<br />

 

d&b have always been completely wonderful.

 

In their early days they used to issue a house magazine called "audio plus" Instead of the pile of PR hype you normally find in such things, it was seriously educational and an excellent read.

 

And that company has conclusively disproved the silly British myth that Germans have no sense of humour...