Is it true that with a 70volt amp, you do not need to calculate for headroom (other than line loss and transformer efficiency), and that you can literally load on the speakers until you have used up the entire rated wattage of the amp?
For example, a 70v amp rated at 500 watts per channel stereo. I can tap 5 speakers at 100watts each and use up all 500 watts without worrying about the amp needing more juice for peaks, etc...? (again, taking line loss and transformer efficiency out of the equation)
I'm curious because the venue I reffered to in my other 70volt post has a system in which was just put in very recently and it had an issue the other night. I wasn't there so I dont know exactly what they heard but... here is the scenerio :
THey have a Crown CH4 70v amplfier capable of 500 watts per side stereo. THe one side has 9 JBL Control 266 CT's on it.
5@60 watts and
4@30 watts, with a total of 420 watts. 80 Watts of headroom to allow for line and transformer power loss.
They called me and said that last night they heard some pops at one point and then it sounded like the first speaker in the chain was letting low frequenices through (despite crossover settings) and then randomly getting lower in volume and then louder again, along with sounding muffled. He said the other speakers in the chain were following suit with different less abrupt degrees of issues. He said the amp wasn't clipping ( i was on the phone with him during the incident) and the levels of the system were all in the green, no limiting or compression taking place. I had him turn down the other amp channel and he said the problem seeemed to go away. Considering the other channel is independent of the problem channel, I think it was just coincidence that the problem stopped.
At my test there today, all speakers appeared to be fine with no signs of noise, pops, or any indicators at the amp. However, I could not turn it up (it was dinner hours) to see if it was happening when the amp was serving up some real power.
This leads me to this purpose of this post which is to ask if anyone knows what happens when a 70v amp is pushed to it's max potential or if it is loaded up with speakers that have a combined wattage that is greater than the limit of the amp channel they are on. Even though in this case as I said earlier, it is 80 watts under the channel total. DOes any of the symptoms above sound like anything that could happen if the amp is pushing it's limit or would that cause something entirely different? I'm gonna check out the Crown CH4 manual as I know it will list the protection features for this particular amp but I'm assuming that it would do many things to protect itself other than the wacky issues described above.
thanks as usual,
jeff