Monday 6 February 2012

Lovepedal Eternity Burst - SIP8 inline opamp

After a thread on Freestompboxes, I thought it would be interesting to try out a few layouts using inline opamps and see how they compare in board size.  Tayda sell the NJM4558 which would be perfect for a lot of these effects and so I thought it would be good to see how the layout looked for an Eternity Burst as I have a recent DIP8 layout to compare to.  As you can see in this I managed to save 3 columns on the vero compared to the DIP8 layout I posted today, but an extra row was needed.  I'm sure a lot more space could be saved by people who don't have the aversion to standing resistors that I do, so this would be a good option for some people, especially for high parts count circuits.



16 comments:

  1. Built this today, works great, but looks like Tone 1 & 3 need to be swapped, and Drive 2 should be connected to Drive 3.

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  2. After tracking down the gremlins in mine, I got it working(cold joint)
    It sounds great for a fairly simple build. Can't remember if I changed the tone but did reverse the gain lugs as Alan suggested above.
    Funny side note: It took me forever to find my way back to this layout. I bought the IC and could not remember what I planned to build with it to save my life. I finally came across it and happy I did.

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    1. I was positive I'd already updated this layout. Now done, thanks for the reminder

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  4. Does anyone have a schematic for the Roadhouse variant?

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  5. Hey guys i am having an issue with my build when I turn the tone control almost fully clockwise I start to get some oscillations. Twiddling the guitar volume and tone controls alters the frequency of the oscillations. It happens with a battery or power supply. I saw someone on diy stompboxes that had the same issue but it never was resolved. Any suggestions?

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  6. Hey guys i am having an issue with my build when I turn the tone control almost fully clockwise I start to get some oscillations. Twiddling the guitar volume and tone controls alters the frequency of the oscillations. It happens with a battery or power supply. I saw someone on diy stompboxes that had the same issue but it never was resolved. Any suggestions?

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  7. Hi, Does pin 1 on the IC go towards the top side of the board? eg towards the ground rail side or towards the diode section side?

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  9. I put a klon buffer in front of the circuit and it fixed the oscillation issue I was experiencing when the tone and gain were maxed. When I turned the buffer off the squealing returned.

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    1. Try replacing the 1M resistor from ic pin 5 to vref with something like 22K-120K. This'll lower the input impedance of the circuit, but it'll kill the squeeling.
      +m

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  10. I think the mistake is in this layout. The line "Output" must be called "Volume 3" indeed. Am I right?

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  11. Eugen, you're right on that one, and I think I found another small error. I was troubleshooting this build (only worked when gain was set to zero) and literally going over my work with a magnifying glass when I noticed that the middle cut in the three-cuts-in-a-row seemed to be redundant.

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  12. Bishop, you'll find redundant cuts sometimes because when we're doing the layouts there may have been something that needed isolating that was moved before the layout was finished. So you don't need it, but it won't do any harm and in fact is sometimes useful to keep audio rows away from power rows which could cause noise, as would be the case here. I have put in cuts which may seem redundant in a lot of my layouts for this very reason and in all likelihood that's why this one was there (although I can't remember for sure).

    And Eugen, this is a hobby site that gives people like you something for nothing. We don't get paid for the thousand of hours we have put into it and so occasionally you may find a misnamed label. Often this is due to copy and paste oversights, but usually people from the community we have tried to build will point out errors which are then corrected. That's how a lot of people learn and gain experience.

    If you don't want to run the risk of coming across one again can I suggest you hire your own designer who you can pay to give you the quality you demand. Either that or suck it up buttercup.

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  13. Output goes to Vol 2/ Vol 3 goes to output. Sounds cool. Oh and I dunno if it’s like the original but the tone is wired in reverse. If you don’t like it just swap tone 3 and Tone 1. Thanks for the layout as always. I ordered a few of these ic’s accidentally and decided to spend one on this. Thanks again Ivlark and co.

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  14. I like this more than I thought I would. Screamer derived but with plenty of warmth and sustain. Kinda Eric Johnson type of vibes maybe. I dunno. Btw, B2K seems sweeter as the tone control to my ears. Thanks again.

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