I have two
Crown 602 Amps. Each connected in bridge
mono. Output is 1200W. I have two
Peavey PS2
FOH speakers rated at 500-1000 max 2000w. I want to reduce the stress on the
FOH speakers. What will i loose in DB with 775W vs 1200W into 8 ohms.????
I assume you mean the XLS 602, which is 1,200W into 8 Ohms in bridge
mono mode but at 1kHz and 0.5%
THD, so maybe more like 1,000W to 1,100W for full range operation. Also assume you mean the
Peavey SP2, which is rated at 500W continuous/1,000W Program/2,000W Peak and a nominal 8 Ohms with a minimum
impedance of 6 Ohms. The QSC PLX3602 is rated at 725W into 8 Ohms for 20-20kHz, 0.5%
THD. Thus I'd compare the 725W and 1,000-1,100W numbers or -1.4dB to -1.8dB.
I'm not sure how to calulate this. Will i loose a lot of loudness.
With around a 1.5dB to 2dB reduction many people will not even notice the difference.
The truth is i don't want to fry my super great SP2's. I blew one of them when i had a short but I think i was running them to hot anyway.
The Sp2's sound super great whth the 1200W
Crown amps. I just don't want to keep blasting them.
How about simply turning it down? One can always run a higher powered, greater output
system at a lower
level with more
headroom for peaks while having a smaller amp does not prevent anyone from trying to run the
system just as loud and the problems more often occur when people push underpowered systems too hard. If you are pushing the
system you have then you may simply end up pushing the
system even harder with a smaller amp while if you can get by with a lower output
amplifier then you might be able to simply run your existing
system at a lower
level. The one caveat to this is if you do not have control and others may push the
system harder than you would with your knowing the intended operation.
In fact you might be surprised to find that most of the time the output of the
amplifier in actual use may be a fraction of the rated
power. Maybe look at it this way, a difference of 10dB is typically perceived as a halving or doubling of loudness so an amp putting out 1,000W for the peak levels is outputting 100W for the sounds that are half as loud, 10W for sounds one-quarter as loud and just 1W for sounds one-eighth as loud as the peaks. Or you could look at it from the perspective that highly compressed music might have a 3-6dB
crest factor (the difference between the peak and average levels) and a 1,000W peak output would thus relate to a 250-500W average output. However, some music has a 10dB, 12dB, 20dB or even greater
crest factor, thus the 1,000W peak
level might relate to a 100W, 63W or 10W average
level.
The fact that audio signals generally vary in
level and the
effect that may have on peak and average levels is an important aspect to understand and can affect virtually the entire audio chain. For example, many people do not consider that limiting peaks may not significantly affect the average
level. Or that putting compression or limiting on a signal and then applying 'makeup
gain' may maintain the same peak levels but increase the average levels.
