Marshall guitar amp schematic

Discussion in 'Electronics Resources' started by imperatormk, Apr 29, 2013.

  1. imperatormk

    Thread Starter Member

    Mar 1, 2011
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    Hi. Can anybody suggest me a good PCB schematic of a DIY Marshall guitar amp? Please let me know if you need more details.

    Thanks!!
     
  2. #12

    Expert

    Nov 30, 2010
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    Marshall didn't make do-it-yourself guitar amps. A pcb is different from a schematic.
    I can't post the dozens of schematics I have, on this site.
     
  3. paulktreg

    Distinguished Member

    Jun 2, 2008
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    Search for "guitar amplifier schematic diagrams" on Google images!
     
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  4. bertus

    Administrator

    Apr 5, 2008
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  5. imperatormk

    Thread Starter Member

    Mar 1, 2011
    96
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    Maybe you could upload them on some 3rd party site and link them here?

    I found Marshall amp schematics, but I wonder how would I make a PCB from them? It seems impossible to draw on the board manually and make it correct...

    Any suggestions appreciated!!
     
  6. square wave

    New Member

    Apr 25, 2013
    6
    1
    There's a free version of Eagle that's commonly used for DIY PCB creation. Once you've got the gerber files generated, you can send them to a fab company or try and etch one yourself with a transfer. I've never done my own PCB work but there's a lot of guides around the internet if you take a look.
     
  7. imperatormk

    Thread Starter Member

    Mar 1, 2011
    96
    2
    I have done some PCBs using Eagle already. But this schematic is complicated far more than I can imagine drawing manually. Maybe someone can give me some finished PCB layouts?
     
  8. tubeguy

    Well-Known Member

    Nov 3, 2012
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    Which Marshall amp are you building ?
     
  9. imperatormk

    Thread Starter Member

    Mar 1, 2011
    96
    2
    I have not started to build anything yet, and I don't know what exact model to build. It needs to output ~45w max.
     
    Last edited: May 2, 2013
  10. imperatormk

    Thread Starter Member

    Mar 1, 2011
    96
    2
    Okay, I managed to find a good Marshall amp schematic (in attachments). But I need advice how to make a PCB layout out of it. I can't imagine drawing everything manually in Eagle, and I don't have a better idea.

    Thanks!
     
  11. tubeguy

    Well-Known Member

    Nov 3, 2012
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    Well, hold on to your hat. ;)

    Not sure if you realize this but the 6100 schematic you posted is just the power amp section. You will also need to construct a quite complicated pre-amp circuit for a complete guitar amp.

    This amp is in the 100 watt range, (you had mentioned wanting 45 watts).

    Have you built advanced projects like this from scratch before?

    Must point this out: And do you understand that these are VERY dangerous and possibly lethal high voltage circuits. ???
     
  12. tubeguy

    Well-Known Member

    Nov 3, 2012
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  13. tubeguy

    Well-Known Member

    Nov 3, 2012
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    Here's an example of a kit with turret-board construction to build a Classic Marshall:
    http://triodeelectronics.com/50wmarshkit.html

    Scroll down to the Old and New wiring layouts to see how turret-board construction works.
     
    Last edited: May 4, 2013
  14. imperatormk

    Thread Starter Member

    Mar 1, 2011
    96
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    Let me think about it, I'll post back later:).
     
  15. imperatormk

    Thread Starter Member

    Mar 1, 2011
    96
    2
    Okay, making the Marshall schematic I posted is too big bite for me, so I'll just start by something more simple.

    But I need a little help. I found two schematics using one opamp, one of them is standard amp and the other one offers distortion effect. But I am not sure if that second one is to be used as-is (it's input goes to the guitar, it's output to the speaker) or it needs to be connected in cascade to the first one to work properly (it's input to the other one's output).

    http://www.runoffgroove.com/ruby.html - the *standard* amp
    http://www.runoffgroove.com/grace.html - distortion schematic

    Thanks!
     
  16. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    The shown schematics will output 1 maybe 2 watts.
    You stated you wanted about 45 watts power.

    Here is a page from ESP that has a lot of audio projects:
    http://sound.westhost.com/projects-0.htm

    Bertus
     
  17. imperatormk

    Thread Starter Member

    Mar 1, 2011
    96
    2
    The idea was to start with something simple. The link you posted has only one 100W amp under the 'Musical instruments' section. What I am not sure about is can I use a power amp as a guitar amp in some way? (might be totally wrong about this!) Thanks!
     
  18. tubeguy

    Well-Known Member

    Nov 3, 2012
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    Yes, a 'typical' power amp can be used to make a guitar amp.

    What's required is a preamp designed for guitar. This preamp converts the high impedance low level signal from a guitar into a line level signal to drive the power amp. The preamp can include various overdrive and tone control circuits

    You could start by building a guitar preamp circuit and connect it to a ready made power amp or make a simple power amp using one of the many power amp chips available. This preamp could use vacuum tubes and/or solid state components.

    There are many choices. I'll post some ideas, just out of time now. Check back later !!
     
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  19. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    You can use a poweramp.
    You can make the effects in the preamp.
    On this page from GEOFEX, you will find some schematics for guitar preamps and effects:
    http://www.geofex.com/

    Bertus
     
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  20. imperatormk

    Thread Starter Member

    Mar 1, 2011
    96
    2
    I'll take a look at some schematics and stuff and will post back later. Thanks!!
     
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