Tube preamp scheme.

Discussion in 'Amps [BG]' started by sanyaalwaysbass, Feb 5, 2013.


  1. sanyaalwaysbass

    sanyaalwaysbass

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    Hello everyone! I'm in search of a good tube preamp scheme. It's assembling must not be expensive like alembic f2b or ampeg svt pro.
    I will be grateful for any
    help you can provide.
     
  2. majortoby

    majortoby

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    Well, first thing's first. How conversant in electronics are you? This sort of undertaking can be seriously dangerous and fruitless to the uninitiated. Just a thought.
     
  3. sanyaalwaysbass

    sanyaalwaysbass

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    sorry, i'm forget:

    >Please note, that
    it has to be easy to assemble,
    because my friend-engineer will
    be in charge of that.
     
  4. BassmanPaul

    BassmanPaul Gold Supporting Member

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    Take a look at the front end of an Ampeg B15. It's about as simple and straightforward as a pre-amp can be. If you are wanting to use this to drive a SS stereo power amp, you'll need to add a cathode follower to the output, preferably with some kind of output transformer. That should be a simple task for an engineer with a knowledge of tube electronics.
     
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  6. bgavin

    bgavin Supporting Member

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    Has anybody seen an "open source" schematic for the ultimate DIY design?
     
  7. Codger

    Codger Supporting Member

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    I replied to your duplicate posting over in Pickups & Electronics.
     
  8. MAMMOTHvolume

    MAMMOTHvolume

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    check out the g9 preamp
     
  9. bgavin

    bgavin Supporting Member

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    Link?
     
  10. synaesthesia

    synaesthesia

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  11. ThisBass

    ThisBass

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  12. nashvillebill

    nashvillebill

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    The Alembic is basically a Fender preamp and tone stack, can't hardy get much simpler for a preamp.
     
  13. majortoby

    majortoby

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    I'm detecting english as a second language here. Where are you located? That could help us help you :)
     
  14. fdeck

    fdeck Supporting Member

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    Are you volunteering? ;)

    A nice idea might be to show a preamp build, progressively, starting with the most basic features. A couple of gain stages with a passive tone stack in the middle is about as basic as it gets. Then you can add things like midrange, DI, etc.
     
  15. majortoby

    majortoby

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    +1
    I agree that starting with a very basic pre would be the way to go. At least starting out, you could probably get nice results with a couple gain stages, a SIMPLE eq, and cathode follower.

    It would not be the most versatile device ever crafted, but you would have the ability to tweak it more to your liking, and develop a better picture of where you want to take it from there.

    And you never know, a simple clean pre with minimal eq just might be your dream tone :D
     
  16. BAce

    BAce

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    A single channel Alembic F2B is about as easy a tube preamp build as you will find. And they sound great. I did one a while back and I love it. It was however my 27th amplifier or preamplifier build. Mine isn't exactly stock either--D.I. out as well as the normal output, cathode follower, a few extra switches. So do some reading, look at a LOT of pictures of finished builds to get an idea of how these things are put together.
     
  17. bgavin

    bgavin Supporting Member

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    I wish, but I'm not at all literate in circuit design. Speakers are my thing.

    I've seen a few point-to-point photos here on TB of units that are superbly constructed for ease of service.
    These don't have the compromises required for mass production, i.e. surface-mount, printed circuit boards, pots soldered to boards, etc, etc.

    This is not the correct forum, but I suspect somewhere there is in-depth discussion about circuit design for the ultimate bass preamp.
    My SVP-Pro schematic thread got a bit of discussion going, but it did not continue.
    Some of the smart design guys were chiming in as to why a particular circuit was good or bad, and what was required to improve it.

    I wouldn't object to paying top dollar for a well-designed custom preamp, with full schematic, that is fully serviceable (point to point) long after the maker exits the business.

    My daughter's 1985 JCM-800 is an amp like this.
     
  18. Passinwind

    Passinwind Charlie Escher Supporting Member

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    What's your idea of top dollar Bruce? And how custom would it need to be?

    Personally, I don't consider turret or terminal board construction to be functionally any better or worse than good printed circuit boards -- especially if they're wired by a beginner's hands. The '85 JCM800s used a printed circuit board, BTW. '85 is right around when Marshall started doing board-mounted pots and jacks too, so your daughter's amp is quite desirable if it's the old style build.
     
  19. Clark Dark

    Clark Dark

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    If you're not into the Alembic F2B then try the Fender Dual Showman :meh:
     
  20. Codger

    Codger Supporting Member

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    I mistook the OP's comment to read that he considered the Alembic F2B or Ampeg SVT Pro to be an example of the "must not be expensive" type. :meh: I think you'd struggle to find a tube preamp simpler or less expensive than an F2B. Maybe with no tone controls?
     
  21. dhsierra1

    dhsierra1

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    TBer Passinwind is one of the pre-amp guru's around here, he posts on different builds pretty frequently. Do a search on some of his stuff, then PM him.
     

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