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Amps with high impedence inputs?

Discussion in 'Amps, Mics & Pickups [DB]' started by geoffzilla, Jun 18, 2004.


  1. geoffzilla

    geoffzilla

    Oct 30, 2001
    Nashville, TN
    Endorsing Artist: Aguilar Amplification
    Besides the Acoustic Image products, what other amp manufacturers supply piezo level inputs on their amps? I'm in the midst of looking for a good doubling amp, and one of my main goals is to avoid bringing a seperate preamp to upright gigs.
    If it matters, I'm using a realist.
     
  2. Francois Blais

    Francois Blais Supporting Member

    Dec 11, 1999
    Québec, Canada
    The Euphonic Audio (at least the iAmp600 I own) has active and passive inputs. The passive one has a 1Meg input impedance.
     
  3. In my experience, which I grant you is not all that extensive, I find a big difference between 1 Meg and 10 Meg input impedance for piezos. AI is 10, while the EA and Woods are both 1. With the preamps I've used, the 10 Meg input is responsible for a big improvement in the sound. The Raven Labs, which is what I use now, and the Fishman both have a 10 Meg input. There may be others.
     
  4. Francois Blais

    Francois Blais Supporting Member

    Dec 11, 1999
    Québec, Canada
    Yes, that's true.
    With my iAmp600, I use a TubeWorks 4001 DI, which I modified to raise the input impedance from 1Meg to 3.3Meg.
    There is a clear difference between the EA 1Meg input and the TW 3.3Meg input tone.
    With the 1Meg input I loose some bottom end, and the midrange is more colored, uneven.
    I'm not sure I'd get much difference going from 3.3 to 10Meg though.
     
  5. geoffzilla

    geoffzilla

    Oct 30, 2001
    Nashville, TN
    Endorsing Artist: Aguilar Amplification
    Thanks guys,
    I figured it might be only Walter Woods and AI. I didn't know that EA would be an option as well. Sounds like not many people go without a seperate preamp even with these amps though.
    hmmm.....
     
  6. I have an AI Contra, and I was thinking about using a preamp with it. If I did, which input should I use?
     
  7. When I use my AI Contra with the Raven Labs PMB-1, I find it works pretty well into the effects-return of the AI. I do the same if I'm using the PMB with my GK-150. It maintains the headroom, and doesn't compromise the gain-staging (!)

    - Wil