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Volume difference between bright and normal inputs?

Discussion in 'Amps and Cabs [BG]' started by i_got_a_mohawk, Sep 12, 2005.


  1. Should there be a noticable difference in volume between the bright and normal inputs?

    I never noticed before, but the bright input seems a fair bit quiter on my SVT :eyebrow:

    Its 2 seperate inputs, not a single input with a switch, i should maybe try some contact cleaner? (and hope!)
     
  2. That's normal. The "Bright" input on SVTs is padded compared to the "Normal" one.
     
  3. Oh right, thats a bit silly isnt it?

    One could ask, why ? (seems odd to me anyway)



    [ oh, and thanks for showing it isnt a problem! ]
     
  4. Jerrold Tiers

    Jerrold Tiers

    Nov 14, 2003
    St Louis
    Most of the time, inside there is a high boost, which may not be an actual "boost", but rather a circuit that cuts highs less than it cuts lows, so the result is a boost.... Often these are right at the input... so they interact with the bass.

    Yes it can be done a different way, but then the details of the response may be different, due to interactions with the bass.

    On the standard old SVT, the input on the normal input is into 5.6 megohms through 47K. Very light loading.

    On the bright input, there is a 10 dB cut AND a heavier loading by a factor of at least 30 depending on frequency. That will interact with many/most passive basses. Even with an active bass, it has the 10 dB cut.... you'll hear that.

    The circuit is a total of 150K ohms vs 5.6 megohms, made up of a 100K resistor to the grid, and a 47K to ground.... plus a 0.0047 uF capacitor in parallel with the 100K. (the 47K goes to ground if you don't plug anything into the normal input.)