Can somebody tell me what a "passive preamp" is !?!?

Discussion in 'Tube Audio' started by Bill Ferris, Jun 10, 2017.

  1. Mark B

    Mark B Yamaha Fan Subscriber

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    Pre-amp = before the amp.

    Some manufacturers call a "pre-amp" that provides gain a control amplifier. That more exactly describes the components function.

    A passive device situated between source components and amplifier would more accurately be called a passive line-stage.
     
    Last edited: Jun 10, 2017
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  2. Bill Ferris

    Bill Ferris Well-Known Member

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    Yes I agree... :thumbsup: But not likely to catch on, as it just doesn`t sound sexy enough !!

    Good call though Mark B.. Regards, OKB
     
  3. Leland47

    Leland47 AK Subscriber Subscriber

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    I didn't read the above links....

    But, I had always thought a Passive Pre.....was one of those high-end types that didn't have tone controls....and an "Active" one or just a Preamp did have tone controls.

    I guess I'll have to read up.....as that now sounds incorrect.
     
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  4. Dandy

    Dandy Super Member

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    Next on your misnomer hit-list might be wifi...
     
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  5. Bill Ferris

    Bill Ferris Well-Known Member

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    Yes.. Well put. :thumbsup:
     
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  6. airtime

    airtime Super Member

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    Well now let's add buffer stages into the mix. Now we have "passive buffer preamps" that do require a voltage source, pass audio through a transistor or two but add no gain.

    Modern audio culture has formed the praise passive preamp to mean basically a volume pot in front of the amp - with no gain stages. Much like "sure I enjoy listening to the stereophonics" to mean you listen to vinyl, records, spinning disks, etc...Culture has changed the meaning and phrase to mean what ever is popular at the time.

    With passives and preamps, one does not replace the other. It is all dependent on your setup , gear and listening taste. But mostly your gear.
     
  7. sqlsavior

    sqlsavior AK Subscriber Subscriber

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    ^^^^ This.

    To further muddy the waters, my Promitheus TVC (Transformer Volume Control) is passive, has no power cord, yet provides an optional 6 dB of gain.

    [​IMG]
     
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  8. Lavane

    Lavane AK Subscriber Subscriber

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    There are "passive tone controls". No gain added. But, they can only reduce the gain, not add to it. Cranked up all the way its like they aren't there, think flat responce. So turning them down you are reducing the gain. Where active tone controls add to the gain past center or at 12:00. With active below 12:00 you are reducing gain. After 12:00 you are adding gain. I think I got that right.
     
  9. bshorey

    bshorey AK Subscriber Subscriber

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    Technically there's no 'amp' there. 'Preamplifier' means just that - something that goes in line before the amplifier.

    bs
     
  10. sjfloat

    sjfloat Super Member

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    A pre-amp is *defined* primarily as a circuit that provides voltage amplification ("pre" the power stage, where else?). I have always found the concept of a pre-amp that doesn't pre-amp almost Orwellian; a non-amplifying amplifier.

    It may be a swell box, but it's not a pre-amp.

    Anyway, that ship has already sailed. :)
     
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  11. Bill Ferris

    Bill Ferris Well-Known Member

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    Well put Sir. :beerchug:
     
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  12. Harryconover

    Harryconover Well-Known Member

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    Passive and amp are oxymoron
     
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  13. dyche01

    dyche01 "Buy high. Sell low" Subscriber

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    That's what the entertainment industry calls a 'retcon,' short for retroactive continuity.

    https://en.wikipedia.org/wiki/Retroactive_continuity
     
  14. mroboto

    mroboto Super Member

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    The AMP is PREceded by someting, amplified or not...
     
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  15. dyche01

    dyche01 "Buy high. Sell low" Subscriber

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    So my turntable is also a preamplifier.
     
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  16. mroboto

    mroboto Super Member

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    A turntable never directly "precedes" (précède in french) an amp, but an amplified phono pre-amp that is in face of (precedes) an integrated amp preamp section, or preamp, active or passive (Attenuator), before the amp section.

    If this is only an attenuator, no reason to call it a pre-amp, it's an attenuator, but if there is another additional function, like an input selector, it's an item that deserves to be called a pre-amp, if not, how can we name it without a complete description.
     
    Last edited: Jun 23, 2017
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  17. sjfloat

    sjfloat Super Member

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  18. sjfloat

    sjfloat Super Member

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    So are the interconnects and the stylus.
     
  19. sjfloat

    sjfloat Super Member

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    I can't believe that whoever coined the term didn't know better. I always thought it was just a little tongue-in-cheek.
     
  20. crispycircuit

    crispycircuit AK Subscriber Subscriber

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    With this style passive control box, you need to pay close attention to impedance of input & outputs. The volume/balance pots will need to be a high resistance
     

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