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Switch box suggestions

Discussion in 'Recording' started by Sonicrain, Jun 16, 2009.

  1. Sonicrain

    Sonicrain Guest

    I recently started interning at the Iguana Recording studio in Toronto and among their equipment they have a Radial JD7 Injector switch box which so far I've seen hooked up to 4 amps although I know it's capable of 7. I'm looking for something similar in a reasonable price range for doing recording work at home. I don't need something as extravagant as to be able to hook it up to 7 amps, but I wanted to know if anyone here could give some suggestions on a cost effective but still good quality switch box that could connect a guitar up to 3 amps at once.

    I appreciate any suggestions.
    Thank you,
  2. Boswell

    Boswell Moderator Distinguished Member

    Why not use a pedal with a "clean" setting (not "by-pass")? You can daisy-chain the output of any buffered pedal to lots of amps since it's low-impedance.

    Beware of hum loops when connecting multiple amps to the same source. The JD7 has transformer-isolated outputs to avoid ground loops, but if you have a problem with a particular amp, you could use a pair of passive DI boxes back-to-back for that amp.
  3. iamfrobs

    iamfrobs Guest

    I don't have an answer for your question, but, I have one of my own.

    How do you like Toronto? I'm from the Buffalo area and I often think about heading up there to check out some of the studios. I would love to work up there eventually.
  4. jg49

    jg49 Well-Known Member

    Remy had said that back to back passive DIs were not a good idea due to impedance issues with guitar signals and that after passing thru a DI twice you would lose a good deal of tone.

    "Guitars with passive pickups need to see the high impedance load that tubes provide. A DI transformer will generally not be higher than 50 K ohms. It will affect the tonality. But an active pickup with a JFET input will present the pickups with the proper load, high. And you'll probably need to power that active DI with an internal battery, since you will not be providing phantom the box. Then to the amplifier via XLR cable up to 1000 feet, to a balanced bridging transformer that's 1:1 and say 10,000 ohms, each side."

    Topic link {old-link-removed}
  5. Boswell

    Boswell Moderator Distinguished Member

    Re-read my post. I talked about using the back-to-back passive DI box technique for breaking ground loops after a buffer device such as a pedal. The pedal drives the DI box, not the guitar pickup.
  6. jg49

    jg49 Well-Known Member

    I see. So the pedal alters the impedance issue Remy was talking about? Not certain when you say buffer exactly what effect the pedal has on the signal.
    Boswell "You can daisy-chain the output of any buffered pedal to lots of amps since it's low-impedance." I assume that a guitar pickup is high impedance?
  7. Boswell

    Boswell Moderator Distinguished Member

    Yes, that's exactly the point. It's why long cables having correspondingly high capacitance cause loss of high frequencies, since they form a low-pass R-C filter with the pickup output impedance.

    Some acoustuc guitars have built-in active pre-amps that act as buffers. As a general rule, the type with 9V batteries that go flat in the middle of a gig are the active type and have a buffered output.

    Pedals are generally better in this regard as they are usually fed from external power units, and so can have beefier output buffers. Beware firstly that the "clean" setting on a lot of pedals is just a by-pass switch and in this setting does not buffer the signal, and secondly that many cheap pedals cause degradation of the guitar sound even in their "clean" setting.

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