What makes an amp sing?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by bjm007, Jul 16, 2004.


  1. bjm007

    bjm007 Member

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    I've got a bunch of amps since I've been on a buying spree lately......... Old Marshalls, Fenders, Vox, Bogner, Two Rock, Mojave, Aiken, Divided by 13. Germino and Connie on the way, and on and on............

    I notice that even at equal volumes, some seem to bloom into that great harmonic wailing feedback much more than others.

    Others will squeel long before they will "wail". What are the critical elements of circuit design and/or voicing, tubes, etc that make an amp sing?
     
  2. Pedro58

    Pedro58 Supporting Member

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    Volume!! And lots of it!!
    Seriously, lots of things make it sing. And no one will agree what one thing makes it the best kind of sing, much less what "sing" means.
    For me, power tubes workin' hard.
     
  3. Scumback Speakers

    Scumback Speakers Gold Supporting Member

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    For me, it's the proper gain structure in the preamp, power tube distortion/OD, and a properly setup guitar with good sustain, and medium gain pickups (ala 7-9k pup output).
     
  4. blong

    blong Supporting Member

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    Turn it on and practice, practice, practice.

    You gotta find the settings you like, but any amp can be made to sing if your playing is up to par. I have seen guys plug into amps I would never take a second look at and make 'em sing.

    Bob
     
  5. bjm007

    bjm007 Member

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    This is more what I was asking about, but I'm looking for an even more technical understanding.

    For example - you can put up two identical amps side by side with identical pre and power amp tubes (EL34, whatever...), identical wattage, same cabinet and one may feedback/sing (in a good way) much more than the other.

    What are the most likely reasons that one feeds back and the other doesn't? In terms of components in the amp or the design of the amp, what are the most important factors that make one sing and the other not... ?
     
  6. voodoogreg

    voodoogreg Member

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    Originally posted by blong,,,,,


    You gotta find the settings you like, but any amp can be made to sing if your playing is up to par. I have seen guys plug into amps I would never take a second look at and make 'em sing.


    both of these fit my technical and spiritual ideals for this thread. wel said botha'yun's. VDG
     
  7. WailinGuy

    WailinGuy Member

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    To me, that singing quality has to do with having the proper amount of compression happening, especially occurring somewhere in the upper midrange frequencies (to get that controlled feedback thing happening). For higher power amps, most of this compression needs to be designed into the preamp section, or the amp will have more of a crunching or barking quality and less of a singing quality.

    Too much compression, though, will take away punch and make the amp sound more squeely than singing. So IMO, Yes, you CAN have too much gain.
     
  8. cocheese

    cocheese Supporting Member

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    I'd have to say that it is a combination of a good tube amp, a good guitar, a good player, and (sometimes) a good pedal. The pedal for me these days is the Lockhart Tone Wizard. That thing is totally amazing with my mutt Tweed Deluxe/Plexi/Pro/??? amp. It pushes it oh so nicely up into that singing territory that otherwise I'd have to be peeling paint to achieve. Good stuff Greg!!!! :D
     
  9. spentron

    spentron Member

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    I was afraid you were asking about a singing tonality, which would be much harder to answer.

    Gain vs. frequency is the predominant factor. If the gain is at a frequency of pickup feedback more than a feedbackable note or harmonic, it squeals. And vice versa.

    A seperate question is what it sounds like. The optimum gain vs. frequency for controlled feedback does not have room for treble boost in the problem range, for example. A way this can be dealt with is overall have limited treble gain, but do boost treble post-distortion where it impacts the sound more. Another would be to have a harsher distortion characteristic, for more treble added synthetically. Of course there are many considerations as to sound quality, and many techniques.

    One misconception about tubes is that their distortion is smooth, not bright. Actually they're bright but with a nice transition. Transistor distortion is often associated with harshness and feedback problems due to the treble boost often used to keep from sounding muddy.
     

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