Phono pre-amp discussion

Discussion in 'Vinyl Nutjob World: Turntable and Related Gear' started by JoshMorr, Jan 11, 2016.

  1. yotacowboy

    yotacowboy McRibs Kind of Guy

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    Quick question: when connecting a SUT to a preamp, what's the preferred way to deal with ground? connect at SUT? At preamp? Tie ground between SUT and preamp?
     
  2. Mr.Sneis

    Mr.Sneis Friend

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    My sut has a lift switch, allows you to see what ground arrangement works best. It's clearly better in my case in ground=on position. My turntable doesn't even have an external ground wire! I'm guessing it will go tt ground to sut ground and that's the end of it.
     
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  3. OJneg

    OJneg The Most Insufferable

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    In theory you would want to connect the turntable/tonearm chassis ground to your cable's shield sleeve, which would in turn connect to your SUT's casing and/or shield winding, which would in turn connect to the preamp's chassis ground. It's going to depend on the actual circuit configuration of each stage and the stray capacitances induced in each run. Nice to have the flexibility of a ground lift.
     
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  4. VonAtlas

    VonAtlas Rando

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    I've had similar experiences until recently... I'm getting some form of whine that is visible in digital recordings (viewing the signal in spectrum analyzer mode in audacity)... I have it set up as record player->Mani->audio mixer->digital recorder taking in xlr inputs. The whine wasn't there before, and it shifts in tone over time. it looks like a two dimensional double helix, slowly criss crossing and then separating and converging again. When I disconnect the Mani from the mixer, the whine completely disappears from the digital recorder, and using microphones into those same inputs doesn't yield that noise.

    I recently found out there's a strong local radio broadcast, and I heard someone mention it could interfere with the signal because of the insane amplification needed to boost the signal from the record player... Anyone else having this problem or have an idea on mitigating it?
     
  5. RatSalad

    RatSalad Facebook Friend

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    Sorry not sure how you could mitigate that issue. I have heard about people having this issue with mani but they revised it to have shielding or filtering. Not sure if you have a mani from before or after the change.
     

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