Amp has no mid control and other questions....

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by atomheartmother, Jan 31, 2005.

  1. atomheartmother

    atomheartmother Senior Member

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    First of all, my amp has no mid control. Does that mean there is a set amount of mids?

    Also the reverb/vibrato channel sounds weird so I don't use that channel and only use the normal channel. However, I'd like to have reverb. Is there someway to get reverb in the normal channel? Someone once told me you could run an instrument cable from one of the two inputs in the reverb channel over to the second input of the normal channel to tap in the effects to the normal channel? Is this possible or will something blow up?

    Finally, what is the difference between the two inputs for each channel?

    Thanks.

    Here's a pic of the amp.

    [​IMG]
     
  2. tonezoneonline

    tonezoneonline Member

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    There's not really a "set " amount of mids they just are what they are depending on how the tone stack is voiced.
    The reverb can be added to the normal channel but it will be the same reverb so if it sounds "weird" on the reverb channel I'm guessing it will on the normal channel too.In what way is it "weird"?
    I'm not familiar with your particular amp but in general the difference between the channels is the reverb and tremelo.
    The tone stack may also be voiced different.
     
  3. atomheartmother

    atomheartmother Senior Member

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    The tone in the first channel sounds wierd. It's bright and shrill. I took it to a tech to fix twice (other things as well) and he didn't seem to do anything about the first channel. It doesn't matter though.

    How would I got about getting reverb in the normal channel? It doesn't matter if I turn the reverb all the way up; there is still no reverb.

    Each channel has two inputs (Input 1 and Input 2...actually I don't think they're labeled). What's the differene between the two inputs of each channel?
     
  4. GregR

    GregR Member

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    i think that inputs 1 are normal and inputs 2 are bright. have you checked what happens when you move the preamp tubes around? it's possible one is half-gone, so the reverb is mucked up.
     
  5. tonezoneonline

    tonezoneonline Member

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    Unless you told the tech to put reverb on the normal channel there will be none.I'm still unclear as to what is "weird" about the reverb.
    You may want to try a different tech or try and be more clear in your explanation of what you want done to the amp.
    The difference between the inputs is that one is attenuated more than the other.It has added resistance.
     
  6. atomheartmother

    atomheartmother Senior Member

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    Nothing is wrong with the reverb. The reverb/vibrato channel just sounds bright, tinny, and harsh.


    What does attenuated mean?
     
  7. Wakarusa

    Wakarusa Member

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    Attenuated means reduced. Generally the #2 input is either 3dB or 6dB down (quieter) from the #1 input.

    Bright, tinny, and harsh may be nasty tubes in that channel. Worst case, though, is that the design of the reverb (and/or trem) circuit is what makes it bright, tinny, and harsh -- so adding the reverb to the normal channel may just make it sound nasty too.

    Anybody have a schematic for this beast? Maybe pics of the insides? There's always the chance that the reverb channel has a bright cap on the volume pot which could also be behind the unpleasant sounds.
     
  8. atomheartmother

    atomheartmother Senior Member

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    Here are some pics of the circuit. I have bigger versions, but I had to make them small enough for the site to host them.


    [​IMG]


    [​IMG]


    [​IMG]


    [​IMG]
     
  9. Wakarusa

    Wakarusa Member

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    Can't quite see enough detail. What would work best are two hi resolution pictures -- one looking straight down on the circuit board and tube sockets, the other looking straight at the back of the front panel controls. You can e-mail 'em to me if that would help.
     
  10. TechpriesT

    TechpriesT Member

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    try turning the intesnity and speed down all the way
     

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