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Monday, December 15, 2014

Ramble FX Marvel Drive (version 1)

One of the many Plexi-in-a-pedal options out there, the Marvel Drive has parallel input stages allowing you to create your own blend between the normal "channel" and the treble "channel." Gearmandude can show you better than I can try to explain it:




26 comments:

  1. You can tag this one! Just finished it and sounds awesome!

    Greetings from Brasil!

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  2. https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-xap1/v/t1.0-9/10408572_843593565684511_570581818976263635_n.jpg?oh=f49133209eccbf935424ef2848cb9b67&oe=55563955&__gda__=1430826268_055d2b9dd716518f7c256b221a3f5cd4 btw, this is how it looks like (I did it with a mod for a presence control)

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  3. Great looking build. What did you add for the presence control?

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  4. Thanks! It's actually pretty simple:
    Use a 20-25k linear pot for the Presence control, take the Master 3 wire (from the board) and solder it to Presence lug 3, conect Presence 2 to Master 3 (in this case, straight on the pot) and solder a 22nF capacitor from Presence 1 to ground. The output wire still Master lug 2.
    My english isn't very good, but I hope you can understand the directions!

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    Replies
    1. Your english is better than mine :) Me too, I've added a 22nF but later I decided to change it to 15nF. I did a lot of modifications and I'm planning to make something like a Marshall channel and the other channel is Mesa Boogie.

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  5. Your English is just fine Guilherme! Thanks for the mod!

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  6. Hey I'm getting a lot of noise out of mine and I can't work out why.
    I've set the voltages at q1: 4, q2: 5,q5: 5.35 as per recommendations on the tagboardeffects page.
    I put a switch in for an 18v supply from a 7660s on a daughterboard (which sounds awesome. I highly recommend it).
    Used a 1uF instead of the 680n and about 500pF for the 2.2n.
    I get a ground hum sort of sound that gets louder with 18v.
    I put a resistor from the sleeve of my plastic sockets to my enclosure..
    Could it be the j201s i got from tayda?
    I've looked over everything and all the links look good.

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    Replies
    1. I kinda doubt it's your J201s. I would double check to make sure everything's grounded properly. Is the 1ยต cap you're using electrolytic/polarized?

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    2. Try setting all bias voltages to half first. If you have a fresh battery usually it is higher than 9V it is around 9.2V to 9.6V, so set your voltages to around 4.6 to 4.8. You (may) have a different set/brand/make of J201s so those voltage may not work for you.

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  7. thanks https://www.youtube.com/watch?v=Vr9FlJknwTE

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  8. tem como colocar o controle de presence ?

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  9. what are the settings for each trimpot ?

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    Replies
    1. Set them to about half of your supply voltage, then adjust by ear.

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    2. as I know they are in the middle of my supply voltage (it is regulated 9v)

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  10. I can use linear potentiometer(B)
    instead of logarithmic(A)

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    Replies
    1. You can but it may not give the greatest control sweep. But it will function

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  11. I can exchange the following components by:
    4001 by 4007
    180pf by 150pf
    33k for 47k
    2.7k by 3.3
    820ohms by 1k
    thank you

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  12. friend
    how do I measure the stresses of the J201
    with multimeter?

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  13. Great layout and circuit also. I want to point out one possible mistake in the circuit schematic used. At the end of the circuit there are two low pass filters made by combination of two 50k resistors and two 2.2nf capacitors.

    50k resistor and 2.2nf capacitor make a low pass filter that cuts all frequencies above 1.4 khz wich is unacceptable. Tone is so much muddy. If you change two 2.2nf capacitors with two 470pf you get much better results with low pass filter that cuts all frequencies above 6.7khz.

    Try this, I think you will be happy with results.

    Thanks again for this and all the other great layouts you made so far, you are a really cool dude! :)

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    Replies
    1. No, It's not a mistake Acika. There are other circuit/design (e.g. BSIAB2 & some ROG Projects) which uses this capacitor value for LPF at the later stage of a circuit to somewhat simulate speaker response and some do have higher or lower value. But you change this value, it's what they call modding. :)

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    2. Also try changing the 50k resistors to 15k or 10k, you will also have a slightly higher output volume/level.

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  14. I build the pedal was very good !!!
    I wanted to thank.This site is very good, keep it up !!!

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  15. The layout can fit into a 1590a enclosure if you do it very carefully.
    This is my build:http://subefotos.com/ver/?d8dbf7328f9eaefdbbded46ded4f9ffdo.jpgGreat sounding pedal!.

    Thank you, "Effects layouts". :D

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