ABY opinions

Discussion in 'Effects, Pedals, Strings & Things' started by rastaman, Oct 23, 2005.

  1. rastaman

    rastaman Member

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    I'm in search of an ABY box. I've downloaded Morley's schematics and I have designed one of my own. Before I build or buy one, I figured I'd ask the question on the Effects forum to see what people like, don't like, and suggestions. Please respond.
     
  2. aleclee

    aleclee TGP Tech Wrangler Staff Member

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    If you're using it to switch between two amps, you'll need to do something to avoid ground loops. Otherwise at some point, probably when you can least afford it, you'll have some nasty hum.
     
  3. rastaman

    rastaman Member

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    Yes I was planning on switching 2 heads into one cab that I rewired and added a second jack. I've heard of ground loops but how will you know if you'll have a problem with it unless you try it? If you do, what will resolve them?
     
  4. gtrnstuff

    gtrnstuff Member

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    Safe ground loop solutions for two amps include:

    A/B box with at least one buffered, transformer-isolated output.

    Ebtech Hum-X on the AC plug of one amp.

    Unsafe solution that we did in the old days--3 to 2 wire adaptor on one of the amps. DON'T do this. It's called safety ground for a reason. Just because we got away with it. Like driving without seatbelts. A bad electtric shock can ruin your whole day.
    PB
     
  5. decay-o-caster

    decay-o-caster Member

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    Whoa WHOA WHOA!!! Two heads into one cab?!? Isn't that asking for a blown OT on whichever head isn't going to the cab???

    Where's that rascal John Phillips when you need him? :(

    If you're intent on doing this, check out the Radial Engineering stuff - I know they have a switcher for 2 heads into 1 cab, but there's a tremendous amount of engineering involved to keep from blowing up one of the heads.
     
  6. aleclee

    aleclee TGP Tech Wrangler Staff Member

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    +1

    The good news is that any ground loop issues will be short-lived. ;)
     
  7. Josh O

    Josh O Member

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    +2

    Definetely checkout the Tonebone (Radial Engineering) head switching unit.
     
  8. gtrnstuff

    gtrnstuff Member

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    I read the post to say "re-wired the cab with a second jack", as in "separated the two speakers on individual jacks"

    but if not, fireworks
     
  9. rastaman

    rastaman Member

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    Correct! I have essentially 2 heads into 2 cabs, I just asked what ABY box you effects gurus preferred.

    Ground loops: "A/B box with at least one buffered, transformer-isolated output.

    Ebtech Hum-X on the AC plug of one amp."

    Any others?
     
  10. Josh O

    Josh O Member

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    Well in that case, check out the Tonebone Switchbone. A great buffered ABY box with a ground lift switch and phase inversion. I had a completely passive ABY box for two amps and they both hummed like you wouldn't believe, serious ground loop problem. It was so bad that even the Ebtech Hum-X's didn't do the trick and I used one on each amp. It wasn't until I got the Tonebone that I was in the hum free zone. I would think the Lehle would be just as good.
     
  11. mtndog

    mtndog Gold Supporting Member

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    Lehle Dual has been flawless for me, although not the least expensive available.
     

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