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I've noticed that very phenomenon myself on the ham bands. In fact, not long ago I posted here about how I couldn't figure out why I kept getting very good signal reports even though I know I was using a class C amp. I try very hard to never overdrive an amp, so I figured that had something to do with it, plus I use low-pass filters on the output. Knowing that class C amps cause splatter and distortion, it didn't make sense to me at the time, until I realized that most of the distortion produced by class C RF amps is found in the RF portion of the signal, not so much in the AF portion. In other words, it's mostly the RF carrier that is distorted more than the AF voice. This causes IMD, splatter, harmoncs etc, and even does in extreme cases audibly distort the AF as well.

I'm kind of an amplifier snob in that I value a clean, low-distortion signal that doesn't splatter out of band. For me, even more than audio cleanliness it's about consideration of other operators and radio services. Using unfiltered class C amplifiers causes interference on many levels and on many frequencies other than the primary xmit frequency, plus the audio can pay a price in clarity, so given these facts it would seem like the world would be a better place with fewer unfiltered class C amps.. but alas there is always room for improvement in life, so this is no exception. I'm sure with the vast majority of CB amp builders it's about impressing your buyers with the most brute power possible for the cheapest price though..

<blockquote data-quote="eagle1911" data-source="post: 266627" data-attributes="member: 17129">I&#039;ve noticed that very phenomenon myself on the ham bands. In fact, not long ago I posted here about how I couldn&#039;t figure out why I kept getting very good signal reports even though I know I was using a class C amp. I try very hard to never overdrive an amp, so I figured that had something to do with it, plus I use low-pass filters on the output. Knowing that class C amps cause splatter and distortion, it didn&#039;t make sense to me at the time, until I realized that most of the distortion produced by class C RF amps is found in the RF portion of the signal, not so much in the AF portion. In other words, it&#039;s mostly the RF carrier that is distorted more than the AF voice. This causes IMD, splatter, harmoncs etc, and even does in extreme cases audibly distort the AF as well.I&#039;m kind of an amplifier snob in that I value a clean, low-distortion signal that doesn&#039;t splatter out of band. For me, even more than audio cleanliness it&#039;s about consideration of other operators and radio services. Using unfiltered class C amplifiers causes interference on many levels and on many frequencies other than the primary xmit frequency, plus the audio can pay a price in clarity, so given these facts it would seem like the world would be a better place with fewer unfiltered class C amps.. but alas there is always room for improvement in life, so this is no exception. I&#039;m sure with the vast majority of CB amp builders it&#039;s about impressing your buyers with the most brute power possible for the cheapest price though..</blockquote>

[QUOTE="eagle1911, post: 266627, member: 17129"] I've noticed that very phenomenon myself on the ham bands. In fact, not long ago I posted here about how I couldn't figure out why I kept getting very good signal reports even though I know I was using a class C amp. I try very hard to never overdrive an amp, so I figured that had something to do with it, plus I use low-pass filters on the output. Knowing that class C amps cause splatter and distortion, it didn't make sense to me at the time, until I realized that most of the distortion produced by class C RF amps is found in the RF portion of the signal, not so much in the AF portion. In other words, it's mostly the RF carrier that is distorted more than the AF voice. This causes IMD, splatter, harmoncs etc, and even does in extreme cases audibly distort the AF as well. I'm kind of an amplifier snob in that I value a clean, low-distortion signal that doesn't splatter out of band. For me, even more than audio cleanliness it's about consideration of other operators and radio services. Using unfiltered class C amplifiers causes interference on many levels and on many frequencies other than the primary xmit frequency, plus the audio can pay a price in clarity, so given these facts it would seem like the world would be a better place with fewer unfiltered class C amps.. but alas there is always room for improvement in life, so this is no exception. I'm sure with the vast majority of CB amp builders it's about impressing your buyers with the most brute power possible for the cheapest price though.. [/QUOTE]

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