modding a phase 90

Discussion in 'Effects, Pedals, Strings & Things' started by royd, Jul 30, 2006.

  1. royd

    royd Member

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    Friends,

    I just traded for a modern phase 90 and it really is unuseable for me as it is. I'm trying to decide whether just removing the R28 is enough (or putting it on a switch) or if I also should remove the C11 & C12? And if I remove the C11 & 12, what happens if I still put the R28 on a switch? What do you all think? Is there anything else I should change while in there?
    thanks
     
  2. Last Nerve

    Last Nerve Supporting Member

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    When I had one a few years ago, I just did the R28 mod. Completely removed. Made a WORLD of difference. You could always unsolder the R28 incase you like it better back on there (doubt it) or want to install a switch at a later date (possibly?).
     
  3. Tuberattler

    Tuberattler Member

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    I just did the R28 mod with a Keyboarder's 90 and it made it sound a lot nicer even for guitar. Then he did the two caps and now it's really sweet, go all the way!!
     
  4. royd

    royd Member

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    here's what I've found online...

    1) Removing the Pre and De-emphasis will result in a slightly higher noise
    floor while raising the headroom at 1.3Khz +3dB and 7.2Khz +12dB. Procedure:
    Remove C11 (.01MF) and C12 (680PF).
    2) Removing the feedback around the Phaser circuit will diminish
    regeneration. This will result in a mellower effect, reduce the midrange
    frequency response, and sound more like the earlier SCRIPT MXR Phase 90s.
    Procedure: Remove R28 (24K).
    3) For lowering the overall effect output change R7 from 150K to a 100K
    or -3dB reduction, R7 150K to a for -2dB reduction. This modification
    should only be done in conjunction with modification #1.
     
  5. GtrWiz

    GtrWiz Member

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    has anyone tried, or heard, these mods on an EVH Phase 90? if so, what effect does it have?
     
  6. royd

    royd Member

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    OK... I found some more ino over at aron's stompbox that includes other changes to make the pedal an exact replica of the script logo...
    http://www.diystompboxes.com/smfforum/index.php?topic=37893.0
    That was more than I felt I needed to do at this point so I removed the r28, c11, & c12. My plan was to unsolder one end so I could reattach them later if I wanted. Well, it is tight in there. I ended up damaging the r28 and C12 so going back would be a little more complicated. Doesn't matter though. I love the pedal now. it is much sweeter, not honky, unity gain (which I wanted)... good all of the way around. I didn't move the trim pot at all because it didn't feel as if I need to.
    All in all, it made a pedal that I would never use a part of my signal chain. :AOK
     
  7. royd

    royd Member

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    if you can get something in there to cut them, I think so. If not, desoldering them may be easier than cutting.
     

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