1w EL84 like a Benson Vinny

Discussion in 'Shock Brother's DIY Amps' started by bhenry83, Mar 16, 2019.

  1. bhenry83

    bhenry83 TDPRI Member Ad Free Member

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    I was wondering if anyone knows how the Benson Vinny gets a single watt with an EL84 and a 12AX7. I've only seen 1w designs like Rob Robinette's micro amps that use a dual triode in push-pull, or single-ended 5w amps with a VVR that brings it down to 1w.

    I'm still mostly a lurker around here, but I'd like to build something in the 1-5w range soon so I'm doing the research.

    I can't find a schematic, but I did find this gut shot in a Reverb listing.

    [​IMG]

    I've played a bigger Benson and it was lovely. Would be really interested if any of you smarter folks could tell me something about this design.

    Thanks!
     
  2. clintj

    clintj Friend of Leo's

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    Straight from the EL84 datasheet:

    250V plate supply, running in single ended Class A in triode mode will get you a brisk 1.5 watts. Lower your plate supply a little and 1W is easy to dial in.

    Sent from my Pixel 2 using Tapatalk
     
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  3. printer2

    printer2 Poster Extraordinaire

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    I built a P-P amp pushing under 3W with a pair of 6AK6's. They do 1W in SE. 6CU5 will do 2W SE. 6AM5 - 1.4 Watts. 6AS5 - 2W.
     
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  4. printer2

    printer2 Poster Extraordinaire

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    And 1-2W the 6aq5 in triode or pentode depending on your voltage.
     
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  5. printer2

    printer2 Poster Extraordinaire

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  6. gigante

    gigante TDPRI Member

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    You're about the only one I can find on this site talking about building with 6AK6s. I'm trying to decide between a few options right now using an old regency radio. That micro champ was one direction I considered but he mentions he doesn't like the overdrive of the 6AK6. Thoughts?
     
  7. printer2

    printer2 Poster Extraordinaire

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    Personal taste? I did have a P-P so there is a difference there. I made a mini 5E3 where I exceeded the voltage suggestions of the tube running around 230V rather than 180V. Mind you that makes sense in Class A. What is the radio model, what output tube did it use and impedance of the speaker. Might as well try and work around it.
     
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  8. shortcircuit

    shortcircuit Tele-Meister

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    Here's my 6AK6 build: http://www.tdpri.com/threads/nano763.882598/. The OD is great.
     
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  9. printer2

    printer2 Poster Extraordinaire

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    The circuit you plop the tube in determines some of the sound of the amp. 6V6's in a 18W (Marshall) amp does not sound all that different from EL84's. Again a P-P 6AK6 amp but sounds like an amp. The buddy of mine just set up the amp and went at it, he did not know what he could get out of the controls, just winged it. He has some reverb in the first part but then shut it off. Right click on the link and download it to play.

    https://onedrive.live.com/?cid=443A...!119&parId=443A2F0DB3904EFD!109&action=locate
     
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  10. gigante

    gigante TDPRI Member

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    MR-10. I started a thread here about it, but haven't made any big decisions yet. I think I'll answer your other questions there to not clog up bhenry's thread with my distractions.

    Thanks, I really like it.
     
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