How is the drive channel working?

Discussion in 'Amp Input - Normal or Bright' started by Ferpie, Aug 18, 2021.

  1. Ferpie

    Ferpie Senior Stratmaster

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    I understand that tubes are getting saturated on the clean channel and break up into distortion, but I'm trying to figure out why is it that when I click on the drive channel it gets into madness?

    lets take a jcm800 as an exemple...

    also, is there different ways to make an amp saturate?

    what about solid state?
     
  2. AxemanVR

    AxemanVR I appreciate, therefore I am... Silver Member

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    `
    Whether you're playing clean or dirty there is one important concept that makes an amp "feel" like it does, and that concept is called "Gain".

    Gain is what makes and amp sound rich, fat and delicious. A properly set clean gain can make a guitar sparkle and shine while a poorly set one can make it dull and drab. The same goes for overdrive and distortion. Finding the distortion sweetspot can make your guitar sing, otherwise everything can turn to mush. There are obviously other components than just the tubes used to voice the amp as well.

    So, much of it really depends on the gain structure and voicing of each channel. Drive channels typically have more tubes in the signal path to create "cascading gain stages", each pushing the signal strength higher before it slams into the power tubes, which in turn pushes them further.

    Putting a booster in front of a tube amp is one sure way to saturate the tubes more and cause the harmonics to explode. Of course dialing in the right amount is crucial.

    Solid state amps may not react quite the same and some are better than others when it comes to pushing the signal into overdrive, but just because an amp has tubes doesn't guarantee positive results either.

    It really depends on how each circuit is designed and how they react to various signal levels - and how good the player is at recognizing the pros and cons that each amp possesses...


    `
     
    Last edited: Aug 19, 2021
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  3. Ferpie

    Ferpie Senior Stratmaster

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    Thanks for that instructive reply, may I ask for some more info?

    just to clarify, on a jcm800 for exemple, the difference between the clean channel and the drive channel is only the amount of output delivered to the power tubes?

    what goes into distortion in a solid state amp? Is it the same thing in a modeling amp?

    when i put a tubescreamer (for exemple) in front of a deluxe reverb (for exemple),
    The only thing it does is push the signal harder in the preamp?
     
  4. Agtronic

    Agtronic Senior Stratmaster

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  5. Robins

    Robins Dr. von Loudster

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    No, the JCM 800 produces most of the overdrive in the preamp.
    It adds distortion in the power amp when pushing the amp.
    But that is beyond ear bleeding.

    It is more complicated in detail.

    All the best,
    Robin
     
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