Those are average power amounts though, aren’t they? I was told years ago that I couldn’t run a 2 pill behind an S9, BS I said. Have ran the same amp behind the same S9 forever and a night - that’s eons to you and me, Russ. Was told the same thing about the 4300HP I sold new to a guy along with a 2 pill. He ran it daily for several years without so much as a hiccup.
I’m not saying anyone who says it’s not a good idea or it’s not the correct thing is wrong, I’ll agree it’s not the best idea in the world. But like I said before, I know it can be done cause I have a friend who is running a 2 behind a 655 on a daily basis. Still not the best idea anyone could come up with and I’m sure it’ll get one at some point. I have yet to experience it though. I do think a straight 4 would be a better choice.
Good question.
Here's the way it was explained to me by one of the moderators:
Look at the data sheet for the transistor in the amp, they have a voltage requirement, input power requirement, and an output spec, as well as other bits of info. It states that they are spec'd to run at 12.5v; all of the output curves on that page use that standard. Yes, they can run at 13.8v. But each time we push it out of its designed zone we stress the device further.
So, let's say that we have a 2290 (or mrf 454s or any other small pill) 2 pill amp. Spec sheet says that it requires no more than 5w of drive each pill to reach saturation for full output. We have two of them in that amp; so it requires no more than 10w input to get full output (2 x 5w = 10w). Now a 2879 pill spec sheet has a greater requirement of 10w per device; so therefore a 2 pill 2879 amp needs no more than 20w for total saturation to produce full output.
What happens when we go outside of the spec sheet from the mfr? Distortion - for one. Strong harmonic output also on other freq other than the one we intend to TX on - for another. Part is running more voltage and has more input power too, so now it is being stressed and heating up. Things are adding up. If we push it even farther, not only is it throwing off harmonics, we are now courting its failure. Sure a watt meter will show more output, but once we push it out of its designed spec range, we cannot count on it to perform clean and safe. A watt meter is essentially blind and dumb, in the sense that it reads any watts put across it circuits and doesn't discriminate if they are either on freq or several channels away. So we think that all is well and fine; right? Wrong!
So the point is: we don't have to push more watts into the amp to get more power. Simply because it stops making usable power once we do that. A 2 pill 2879 is going to have clean and full output with just 20w. Twenty. Just 20w; and no more is needed.
So along comes the export radio. The dual 1969 bipolar transistor radio has 35-40w output, so the 4 pill 2879 amp will work fine within the input specs. A 40 channel single final/1969 CB radio has a 20w output, and will work within the spec of the 2 pill 2879 amp. But now we have mosfets radios that have 60w with dual finals. SO either we turn down the radio to the spec of the amp, or we get crap out of an over-driven amp and blow it up somewhere down the line and wonder what happened.
Does it matter who builds the amp? Nope; because the spec sheet for the device is still dictating how it operates and what it requires.
SO the radio has a say in all of this too. If we remove the limiter we cause the radio to create more distortion because we are now feeding the radio's finals a distorted audio signal. And you guess it; the amp is forced to amplify all of that same distortion too. Crap in; means there will be - crap out. Plus whatever distortion we create in the amp because we have gone further past its input requirements. So we don't have a bad azz radio setup; we just have a bad radio and a bad system - overall . . .