Best high powered low noise Dual op amp?

Discussion in 'Effects, Pedals, Strings & Things' started by tonesearchin', Apr 20, 2008.

  1. tonesearchin'

    tonesearchin' Member

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    I am looking to switch around some op-amps on some pedals I have - They are both socketed

    A Lovepedal eternity - At first I thought this one was broken when I got it. I guess I was expecting more drive. I switched this one for a JRC 4558d (new issue) and it sounds better but there is just too much noise.

    and the Hermida Mosferatu - This one sounds good It just needs more punch.

    I would like to have some more compression in both of these but I suppose that doesn't have anything to do with the op-amp. I just bought the Eternity but I can't get them to answer any of my emails. So I guess I am on my own.

    Any help would be great!
     
  2. amp_surgeon

    amp_surgeon Member

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    I don't think you need to swap the op-amps. The gain is determined by the value of the input and feedback resistors.

    This wikipedia article covers most of the basic op-amp circuits, and provides the formulas to calculate the gain. Just look at the resistors which are already installed and do the math to calculate the gain. Then, do the math to calculate the gain you want, and get the appropriate resistor values.

    BTW, many op-amp chips do NOT have the same pin-outs. You could fry the chip or other components in the circuit by installing the wrong type of op-amp.
     
  3. tonesearchin'

    tonesearchin' Member

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    Thank you for the response - These are 8 pin op-amps. I had never heard that they could be pinned out differently. Swapping the op-amp defiantly brought more gain/distortion out of the Eternity pedal but there is more noise now. If what you say is true maybe I am using the wrong wording to describe what I am looking for. The op-amp that was in this pedal when I got it was sanded on the top so I don't know what it is. But swapping it for the 4558d certainly brought a different sound and now sounds great with the 5f1 Champ clone

    I will check out the article

    Thanks!
     
  4. Stressfest

    Stressfest Supporting Member

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    I've swapped out most of my op amps with the Burr Brown opa2134pa. It may be a little too hi-fi sounding, but i dig the clarity. Worth a try ;)
     
  5. Unabender

    Unabender Member

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    The keyword (and the ones you are looking for) is "dual op-amp".... It has actually two "amps" in one.

    I think every dual op-amp actually has the same pin out (4558, NE5532, LM358, TL072, ...).
     
  6. missing_dave

    missing_dave Member

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    http://www.thegearpage.net/board/showthread.php?t=142539

    heres a thread on some of this (clip links are down) but its a start on the several threads on this.
    i also was involved in a thread where sean (mr lovepedal) added :

    the E's sound is in the chip..so change it out for a different sound..he listed 3..ill try to find it.


    here is the quote from sean:

    GRAB A TL072ACN chip from mouser.com
    you will be amazed at how that circuit morphs into something else entirely..

    a LM1458 is another chip that will do something else..

    then you will have 3 completely different options.. like I have always said.. the key to the E is in the chip not the circuit
     
  7. dbeeman

    dbeeman Gold Supporting Member

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    Burr Brown OPA2604 is a good low noise
     
  8. tonesearchin'

    tonesearchin' Member

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    Thank you for all of your help guys!

    Right now I have quite a collection of pedals - I bought a collection of 20 to see what I really like. I wanted to try them all and sell the ones that either weren't what I was looking for or were just too expensive to keep in my collection.

    From that 20 I have narrowed it down to a few.

    The Barber Direct Drive is my favorite so far - That may give some of you some insight into what I am looking for.

    Catalinbread Silverkiss - Not the distortion on this one so much but the versatility - This one adds some serious volume/gain and EQ!

    H.B.E. Big "D"

    Arion Tubulator - Believe it or not this one sounds the best with my champ. I have a mod kit for it but haven't installed it yet. I am afraid to for fear that it would lose the sweet tone.

    Hermida Mosferatu - Good but not the high gain beast that I thought it would be.

    Lovepedal Eernity

    Unknown lovepedal - Anyone recognize this? It really needs an LED and AC jack - It is either a copy or a very early pedal. In either case it sounds like a cranked marshall and I love it

    [​IMG]
     
  9. tonesearchin'

    tonesearchin' Member

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