New 5F2A build

Discussion in 'Shock Brother's DIY Amps' started by HBamps, May 28, 2020.

  1. HBamps

    HBamps Tele-Meister

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    It’s been several years since I built an amp from scratch and decided on a simple, low power and volume, classic. The only mods I plan to do is to add a Framus mid control and omit the tone control, for now. I want to see what the high end response is without the 5F2A tone control and possibly add it, or a simpler treble roll off circuit.

    Since being stuck at home, a 5W amp seems like the perfect thing for both low volume playing and to keep my mind busy.

    All parts purchased and on there way to me. I thought it’d be fun to do a little diary on the build to document all the challenges and successes.

    More than just a pile o’ parts. Here’s the first bit of real progress. I measured the components and drafted the board in ACAD, printed to scale to get the template for drilling for eyelets. I could of bought one of the board options from mojotone but wanted to do it myself.
     

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  2. King Fan

    King Fan Poster Extraordinaire

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    I admire all the skills on display here, CAD, beautiful DIY board, etc. Envious, me.

    But is the board photo flipped L<->R? Or did you wire up the wrong side? Hmm, wait, it's like a Hendrix lefty guitar. No, I'm missing something here... :):):)
     
  3. mjcyates

    mjcyates Tele-Meister

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    I just built one of these with the Framus Mid Control and the normal Tone Control. They actually work pretty good together.
     
  4. Lowerleftcoast

    Lowerleftcoast Tele-Afflicted

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    I think your bias cap is backwards. Unless you have the board wired differently than stock.

    EDIT: oh I see you do have it wired different... never mind. But why?
     
    Last edited: May 28, 2020
  5. HBamps

    HBamps Tele-Meister

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    Haha, yeah the board does look backwards! I took the Hoffman layout, which is kinda weird but really ingenious actually, I just changed the preamp a little.
     

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  6. HBamps

    HBamps Tele-Meister

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    Progress. Got all the heaters (don’t miss that at all), rectifier and power wired. Board mounted. Wiring in pic looks a little messy but haven’t tidied up yet. I’m hoping I can get things looking clean for the finished product. These little tweed chassis are tight little suckers!
     

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  7. HBamps

    HBamps Tele-Meister

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    I got this amp running and, with some tweaks, I think it's sounding really great. I am still searching for a speaker that I really like but thru a 1X12 cab it's sounding really great.

    I ended up with the following signal path. Input -> V1a -> Vol -> Framus Mid -> V1b -> high cut tone control -> 6V6. When I had the high cut following the mid control I felt it affected the taper too much and with it after the next gain stage, it's doing what I want (just shaving some highs).

    I also experimented with cathode bypass caps on both V1a and V1b and found I am liking both unbiassed the best so far. Second fav was just V1b. I guess Im a rebel.

    I am awaiting shipment of a Eminence 1058 hoping it'll give me something closer the low end of a 12.

    Anyhow, this is a really fun amp and sounds great at low volumes. I have wanted a good amp for quiet home practice and when I play with singer/songwriters. I think this is going to be a perfect solution!
     
  8. mjcyates

    mjcyates Tele-Meister

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    WGS G10C will give you the low end of a 12".
     
  9. HBamps

    HBamps Tele-Meister

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    Thanks for this tip. I'll keep it in mind.
     
  10. HBamps

    HBamps Tele-Meister

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    This amp is pretty much complete. I still want to refine the treble response and gain but it's sounding pretty good! Here's a clip, note that I am using OD pedals, as pretty much always do.

     
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  11. James Knox

    James Knox Tele-Meister

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    I’m also trying to sus this out on my 5F1. Do you have both of these on a mini toggle switch, or did you audition them in and out of the circuit while playing?
     
  12. James Knox

    James Knox Tele-Meister

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    Beautiful tone. What pedal do you use in this clip?
     
  13. HBamps

    HBamps Tele-Meister

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    alligator clips
     
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  14. HBamps

    HBamps Tele-Meister

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    I am using a JHS Morning Glory, JH Fuzz Face with the volume rolled back on the lead part, delay.
     
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