This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Friday, March 18, 2016

Cornish Buffer

Got a request for the Pete Cornish Buffer in dual form like the one I did with the Klon Buffer. So here's both a single and a dual Cornish Buffer. The original uses a 1N5401 for polarity protection, but a 4001 or similar will work too. And you can probably get away with a small value on the power filter cap (220µ).

20 comments:

  1. I am really excited to see this buffer. I was looking at this and was wondering how you recommend wiring? I was looking at the layout at http://3.bp.blogspot.com/-DSD3O8O8mx8/U5rGpCi5KgI/AAAAAAAAHzQ/u5fPoB7Dgwo/s1600/Cornish+G2+bypass+buffer+wiring.png
    and was wondering how you would wire the in and out buffer option. Also I was wondering if you were thinking of layouts for the Cornish G2 and SS2 as well? I appreciate all that you do. I love this site.

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    1. Thanks! You'd wire it the same way as Mark's drawing. Input jack would go to the In pad of the buffer, Out pad to the switch. The same lug of the switch the buffer Out is wired to would connect to the In pad of whatever effect you're using and the Out pad of that effect would connect to the switch where Mark's drawing says "Vol 2". Hope that helps!

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  2. The single one is verified.I would install it into my guitar!

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    1. I thought about doing this.
      as I've connected it to my guitar strap connected by a 7" cable and it definitely added more fidelity than placing it 20' down the line.
      honestly this buffer does very well being 'overused' every single one of Petes standalone pedals has this on this I/O. I always make sure to have this at the beginning of my chain and at the end on the way to the amp.

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  3. I have a problem with this pedal. I've made 3, 1 in protoboard, 1pcb and 1 in a breadboard. Every pedals have a volume drop. I don't know if this volume drop is normal. I use a bc549b, and the same values of the template.


    Who could help me?

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    1. Try using a BC549C. The B version is much lower gain.

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    2. Also I've tried with bc547 with more hfe and 3904 with the same result.
      Don't you notice volume drop in your Cornish Buffer?

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  4. THANK YOU
    it worked very well without volume drop

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  5. I'm wondering about the 1N5401 diode.
    I've done this build, and it seems pretty accurate.
    I'm not by any means an electrical engineer. I've just done couple DIY's
    BUT the 1N5401 it doesn't seem to be in the pictures and it's not in my OC-1 that I have opened or my TES that I purchased that was open.

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    1. It's for polarity protection and was probably on the main board of production models. I included it on this board as people have used it as a stand alone effect.

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    2. thanks. I just saw this.
      I understand this now...
      you are the first person to respond to this and confirm what I assumed.

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  6. Sorry, i have a question.
    I do not remember where but I read that the 50k resistance is fine so if the buffer is used alone. Instead, if the buffer is in front of an effect, the 50k does not go to ground but connected in series between the 150R and the output. It's right?

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    1. It's quite possible. I would probably just remove the 50k resistor all together if it were me. YMMV

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  7. hello I have the same problem of alb ie a drop in volume, I followed the pattern as it is in the picture. How can I solve?

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    1. I would try just removing that 50k resistor if you're getting low output.

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  8. can i replace non standard R values with standard values? like... 7.5k by 8k,20k by 22k,50k by 47k, 200k by 220k?

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  9. I built this and it definitely is a nice buffer but I've found that it does cause some noise problems with other pedals in my chain, for example I now get a pulsing noise from my univibe even when it's switched off, but if I disconnect the buffer that noise goes away. Plus, it makes my fuzz pedals more noisy. It is lovely with just a clean sound though, and also really enhances my tubescreamer, so I'll probable keep it for certain situations. Thanks for the layouts on this page... I've made three from this site so far and they've all worked first time! Peace :)

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  10. *update* It turns out that I've uncovered a few gremlins in my pedalboard, so the noise issues weren't anything to do with the Cornish buffer. Apologies for any confusion ;)

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  11. *update 2* The Cornish buffer has been on my pedal board for about a week and it's definitely a keeper now! In my setup it works best as the second in my pedal chain after my compressor...

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