First build. 5E7 PRO.

Discussion in 'Shock Brother's DIY Amps' started by ginomolinari, Oct 28, 2019.

  1. ginomolinari

    ginomolinari TDPRI Member

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    Good morning to everybody. I just wanted to introduce myself and my first build. At this point I have a self built pine cabinet with a coffee bag grill with a 15" WGS G15C. The cabinet is open back and quite wide and I am hoping to emphatize the room effect when placed at least 3 feet away from any wall. (nerdy details)
    5E7_006.jpg 5E7_007.jpg
    I have a Weber chassis, Classic Tone iron and I have self sourced all the parts, with the help of a old audio engineer friend. I quickly realised the value of buying a kit vs sourcing. I have now a small collection of wrong parts that is constantly growing. I have been using Mouser even though it gets a bit expensive with shipping and taxes to Italy.
    So far I am done with populating the board (besides the bias circuit) and it already looks pretty mixmatchy. The 220K 1watt resistors are an eyesore. But I am trying to get over it. I am using metal film Vishay for everything but the plate resistors which are carbon comp (they seem to be unusually close to specs, for now).
    5E7_010.jpg 5E7_011.jpg 5E7_012.jpg
    I would love any feedback on the building process and parts sourced. Thank you!
     
    Tube Life, idjster and King Fan like this.
  2. RollingBender

    RollingBender Tele-Afflicted Vendor Member

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    Love the cab!!!
     
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  3. John E

    John E Tele-Afflicted

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    I had a 5E7 that Mark Norwine built into a burnt out Fender Blues Deluxe. Had an EV12L. Weighed about 700 lbs... lol. Was loud enough to cause a stampede in Africa with the volume on 3.

    It was absolutely without question the very finest clean sound I have ever had in any rig. The way Mark structured the volume was it sounded incredible even with the volume on 1. Didn't need to be up loud to sound (SO) sweet.

    And yes, another one I stupidly sold due to G.A.S.
     
  4. D'tar

    D'tar Friend of Leo's

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    Looking great! IF you don't like the grid leak resistors change them out. Really no need for a 1w in that position. IMO.

    Love the grill cloth!

    Only thing I would change on the board is rotate the zip tie so the locking head is against the board for a cleaner look. :)

    Keep it coming!
     
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  5. ginomolinari

    ginomolinari TDPRI Member

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    Thanks. I previously had 1/2 watt resistors for everything but the B+ droppers. However, after reading the specs of the Vishay metal film resistors I realised many have a voltage rating of 250. So i got scared and upped to 1 watt. I didn’t expect to be gigantic like that.
     
  6. King Fan

    King Fan Friend of Leo's

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    Nice build. Self sourcing is a pain, isn’t it? But extra points for effort.

    Speaking of wattage, whats the rating of the tiny and small MFs on the right end of the board?
     
    Last edited: Oct 28, 2019
  7. D'tar

    D'tar Friend of Leo's

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    I undestand:)

    Those resistors should never see anything close to that voltage.
    I enjoy sourcing my own components knowing I'll have enough spare parts for a whole other build!!!
     
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  8. idjster

    idjster VERY grateful member Ad Free Member

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    Great build! Looks terrific!
     
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  9. ginomolinari

    ginomolinari TDPRI Member

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    Thank you for the encouragement!
    The 820 ohms resistor is a Vishay 1/2 watt and rated 200 volts. I know it's crazy small but I feel it should be safe in that position.??

    The grill cloth is a coffee bean bag I got from a local roaster. He thought it was a fun idea so he let me pick my favourite bag from a big pile.

    Every day I learn something new and every shipment of parts is like WTF did I just order? Why doesn't anything look like everybody's else build? I guess that's part of the fun.
     
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  10. dan40

    dan40 Tele-Afflicted Silver Supporter

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    The cathode resistor and grid leaks only see a few volts as D'tar mentioned. No problem using the smaller resistors.
     
  11. ginomolinari

    ginomolinari TDPRI Member

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    OK, here is one of the many times when I get discouraged. I tried to implement a bias pot like I've seen many do and decided to go with a 22k trim pot and a 44k resistor. I even wanted the 1M safety resistor. So the upside is that the trim pot is very accurate to the decimal point. The bad thing is, well, obviously, it sucks! It is my first build and I wasn't expecting to win the price for neatest build but this is pretty bad.
    My question is, besides the looks, is it even safe?
    Any word of advice would be extremely welcome.
    Thanks.
     

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  12. joeford

    joeford Friend of Leo's

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    I've seen uglier on my amps and didn't die or get electrocuted. but maybe you could do a panel mounted pot so you could dial in the bias without having to open it up? hate to see a little dangler like that when everything else is so clean
     
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  13. ginomolinari

    ginomolinari TDPRI Member

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    Radioshack PCB?
     

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