ubuyguitars 5E3 project

Discussion in 'Shock Brother's DIY Amps' started by RollingBender, Apr 18, 2019.

  1. SacDAve

    SacDAve Poster Extraordinaire

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    :eek: sell sell 26 OMG
     
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  2. awasson

    awasson Poster Extraordinaire Gold Supporter

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    All this time I thought you had bought all of the extra 5E3 chassis when they were on sale but it was @ecoast :eek:

    When they were on sale I went to the site but they sold out before I could get one. The listing was still on the site but they had no stock. I kept going back for maybe 6 months checking and even contacted the guys but they never got any more. What a killer deal those were. I ended up buying a bunch of octal and 12 pin sockets and a few other things. Everything seemed to have decent prices.
     
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  3. muswell_hillbilly

    muswell_hillbilly Tele-Meister

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  4. muswell_hillbilly

    muswell_hillbilly Tele-Meister

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    Error: Duplicate post...
     
  5. RollingBender

    RollingBender Tele-Holic Vendor Member

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    After playing around with the 3-way NFB mod for a few days, I like it enough that I made it permanent by putting the mini switch between the input jacks and the first knob.

    I also tried the Pre phase inverter master Volume. I just temporarily wired it in to play around with it. I didn’t really care for the results...not enough to poke another hole in the chassis at this point. Maybe I’ll revisit that one later.

    I think the next mod I’ll try is revoicing the normal channel to a lead channel.
     
  6. RollingBender

    RollingBender Tele-Holic Vendor Member

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    Being that this project is based on the chassis and PT from the big ubuyguitars sale of 2016, the PT is actually the PT from a VHT Standard 12. The voltage of these transformers is 310-0-310 which is pretty low compared to what most folks are using in their 5E3 builds. I’m getting a B+ of 336. I think the combination of the lower voltage PT and the 5Y3 rectifier are contributing to the excessive sagginess that I’m finding a bit unpleasant.

    Suppose this PT could handle the extra draw of a 5U4GB rectifier ( I have a couple of those lying around from organ donors ) or could it handle a GZ34 ( which would take B+ to the positive side of ideal?
     
  7. RollingBender

    RollingBender Tele-Holic Vendor Member

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    I put in a GZ34 and that raised B+ voltage too much. I also tried a 5U4 and though it brought B+ up, it was still quite a bit low and I’m not comfortable with what the extra amperage draw would do to the transformer ( don’t know the specs beyond where it came from).

    I’m out of town for my “day job” but was able to stop at a friend’s repair shop today. He was able to find a NOS RCA 5V4-GA. I’m hoping this will bring my voltages in line with the 5E3 star charts without taxing the PT.
     
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  8. RollingBender

    RollingBender Tele-Holic Vendor Member

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    Here’s the voltage result from the different rectifier tubes...

    118 VAC at the wall
    308-0-308 from the PT

    B+ DC volts
    5Y3GT = 332
    5U4GB = 340
    5V4GA = 380
    GZ34S = 385
     
  9. RollingBender

    RollingBender Tele-Holic Vendor Member

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    I think it was over 2 years ago that I built this cab. Got it cut out and glued together then stalled. Having the amp to go in it now is certainly inspiring

    Rounded the corners and made the back panels...
    DDBD6BD3-A829-4826-A0C4-14986521312E.jpeg
    I used the painters tape and super glue trick to make “double thick” back panels so that the router guide bearing would have something to ride against then they split apart easy with a 10” drywall knife.
    321643AF-F303-4EDE-BA8B-34236708AC90.jpeg
    Just need to glue in the strengthening dowels on the top where the chassis mounts.

    Covering this one with brown tooled leather type stuff.
    D5087ED3-4CC4-4BC3-A155-F0D0DF610970.jpeg
     
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  10. RollingBender

    RollingBender Tele-Holic Vendor Member

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    Mostly done!

    Need to add a handle yet (might try making my own... I have some leather that color matches close enough) and I need to do something with the hole for the standby switch. Maybe RobRob’s Mute switch?

    At idle, it’s very quiet. Strumming a guitar at any setting past 2 is very loud.

    93153AEF-E465-4445-AB6D-5C75A12B1AD6.jpeg
    FA6D209F-CBB8-4AC3-B100-F5D44CF3E481.jpeg
    F0AAB802-38C5-4FCC-9D38-D227DD55B430.jpeg

    Because of the color, every time I look at it, I get a craving for chocolate???
     
  11. BigDaddy23

    BigDaddy23 Tele-Meister

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    Mute switch sounds like a good plan - Is that mini toggle for the Negative Feedback settings?
     
  12. Uncle Daddy

    Uncle Daddy Tele-Holic

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    Paint the inside with some blackboard paint?
     
  13. RollingBender

    RollingBender Tele-Holic Vendor Member

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    Yes, the mini toggle is RobRob’s 3-way negative feedback mod.
     
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  14. Preacher

    Preacher Friend of Leo's

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    @RollingBender check out my "After much trepidation 5E3 build". I made my own handle out of the cheap fender black vinyl handle by wrapping it in the vinyl I was using. It turned out really nice and I have had it for a few months with no issues.

    Great build by the way!
     
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