Sunday, 5 February 2012

Cornish Buffer

This one is sprinkled with fairy dust.  Put it in front of any Boss effect and you'll sound just like Dave Gilmour.  Allegedly.


BUY A KIT

162 comments:

  1. You don't have a Light Drive SS-2 vero to go with this do you Mark??

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    1. I will have soon, it's getting near the top of my "To do" list! :o)

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  2. I've made three of these successfully - so it's verified. Guitar input and send/receive of my effects loop. I use 20 to 30ft cables and this buffer really brings the 'body' of the tone back to life. I can heartily recommend people to give them ago. They cost nothing to make and take no time at all. The guitar sounds so much more musical.

    Thanks Mark.

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  3. Hey mark, can I replace the BC549 transistor with MPAS18 instead?

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    1. You can, but the pins are reversed so remember to rotate through 180 degrees to the way shown in the layout

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    2. Thanks man! I had 3 of those laying around! So excited to make this!!!

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    3. I used the mpsa18 and this thing is the best thing since sliced bread. I love it in front of fuzzes.

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    4. yep, i found out the same thing. it brightens up the top end and actually gives a little more gain to my greer ghetto stomp. love this one.

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  4. Hey mark, what are the voltage for the e. caps? And, is that value consistent for every effect on your site? Thanks again for the help

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    1. It's only really the higher value caps that you'd need to consider voltage. The polyester box and Panasonic caps that I use in many builds, and most ceramic, polystyrene or mica caps are rated at least 50V so you're safe with them for any of these layouts. Electrolytics and tantalums for the higher values should be rated at 16V minimum if youre using a 9V supply, 25V if the effect can accept 18V (and you intend to use it of course). The truth is that most of the caps in the builds will have nothing like the full 9V or 18V going through them, but the power supply filter cap will, and that is always an electrolytic or tantalum so you should stick to the minimum voltage rating convention with those.

      I got some 16V rated 100uF caps and they are tiny (6mm x 7mm), so you can get some compact-build-friendly comoponents if you don't go overboard on the ratings of your electrolytics and buy them that are sensible to your supply voltage.

      If you are using caps that may not be suitable for an 18V supply, then it may be worth considering using a 9V1 zener diode between supply and ground rails, so that any higher voltages are dumped and so protect your components.

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    2. Cool thanks. I kinda just bought the caps without really taking the voltage thing into consideration. I think I got 35-50v rated e.caps so I'm hoping that'll be fine. Thanks for the run down. I'll keep that in mind next time I do a build

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  6. Hello Mark,
    Thank you for this layout. On the 220uf, is the positive side jumped to two of the tracks? I see the neg shares the same "track" as the 9volt and diode, but I'm curious if I'm reading this right. Thanks for any insight.

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    1. Yes with the link, the cap essentially sits between 9V and ground. Caps block DC so their function in instances like this is for filtering the power supply

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  7. Hi Mark, can I use a 1N5400 diode, true? Thanks.

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    1. Yes no problem, or even something like a 1N4001 which you may have to hand

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  8. im building a true bypass looper and want to add this buffer in there (switchable on or off). where do you think it should go? before or after the loops?

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    1. I'd put it right at the beginning, or if you want to reserve the first loop for a temperamental fuzz pedal, put it before the second loop.

      I've heard people putting buffers at the end but it never really made that much sense to me. At the beginning means that all pedals following it (and "capacitance building" cable runs, soldering, jacks, sockets and switches) will benefit from the low impedance provided by the buffer.

      Or for ultimate mojo have a switchable Cornish buffer at the beginning and Klon buffer at the end, so you can do it anyway you want. Then go on TGP and tell them all about it! :o)

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  9. thats what i thought, im putting it right after a tuner bypass mute. im still debating the klon buffer or the cornish. after im done making up this diagram, do you want me to send it to you to see what you think?

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    1. Yes no problem. Seriously though, they don't take up much room and all the components are cheap so why not do both and have switchable switchable buffers? A looper with either a Klon or Cornish buffer has to be cool and it'll only take an extra DPDT toggle. Mention it at the right places and I bet you'd get lots of orders!

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  10. Well take a look at this one im sending over and let me know if ive lost my mind or not haha i think everything looks right, youll have to excuse the messyness. very bored at work and i dont have my adobe illustrator or photoshop handy to make it pretty haha

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  11. Will a 1N4007 work as well?

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  12. Hi IvIark,
    would to test this one on my setup, but could you tell me about wiring ?
    No 3dpt, that's right?
    Thanks

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    1. If you want it permanently on then just wire straight to the input and output sockets. If you want the option to switch it on and off then you could just use a mini toggle to bypass it, it's not the type of circuit that really needs a footswitch because you're unlikely to want to turn it on and off while playing.

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    2. Thanks lvlark, I'm getting ready to build this, and I'm a newbie. If I use a toggle switch, do I use a 3dpt version like this and just wire the offboard like normal:

      http://www.taydaelectronics.com/electromechanical/switches-key-pad/toggle-switch/mini-toggle-switch-3pdt-on-on.html

      Thanks!

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  13. This is maybe the most musical item i have ever had....
    I mean, the way it makes my guitar respond, the overtones it emphasises, the presence and dynamic. Why should i wait 20 years as a (semi)pro and 40 years as a guitarplayer to experience this?
    Everyone should have this little bugger first in their chain to make life better. I almost don't need any overdrive anymore because the guitar sound so sweet itself.

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    1. Well that's a glowing endorsement. No doubt Pete makes some fantastic products.

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    2. I'm guessing you're not joking. If you are, my apologies.

      Mr Cornish will see you as soon as he has finished his tea.
      (http://www.petecornish.co.uk/history.html)

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  14. Done, sounds great! I have read in the official page that the LD-1 can be use it with 18v, can I double the voltage? Thanks!

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    1. As long as your caps are rated above that.

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    3. Thank you and cheers from Spain.

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  15. I made a mistake that sounds so good to me (thats what i thought was the fairydust). I did put in a 1ok resistor in place of the 1k as a failure. Then i build myself another one with the correct values and i missed something. I found the mistake and swapped the correct 1k with the incorrect 10k and there it was, the fairydust thing. It opens it up in a sweet way. The strange thing though is, that the new one doesen't have as much juice as the first one???( are the fairy angry at me?)

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    1. If i could spell right... "doesen't"....

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    2. So do you think it's better with a 10K then? Part tolerances can be a bitch sometimes, there are a number of times that I've made the same effects and you just end up getting one that sounds awesome, and the others don't quite reach the same sort of heights. Sad part is I always end up selling the best sounding ones before I realise they are!

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  16. So far i like the 10k better. It colors the tone a fragtion in a wonderful way, so one day i might think it is not neutral enough. I will not sell mine as it looks like a rats nest..........(Patience has not always been my strongest side)

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  17. A question from a non engineer. How much difference will a 50k Ohm resistor vs a 47k matter in this layout? And a 18k vs 20k?
    The only way i can pay back here, is if you need some music theory explanation. (i have been teaching for many moons)

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    1. If we think those as percentages, the difference in 50K - 47K is little more than 5% and in 20K - 18K exactly 10%

      That kind of variance is not that much, considering that normal (and probably cheapest) resistors are rated with 5% tolerance. Those being the resistors with gold stripe as tolerance mark.

      I know that resistors with silver strip for tolerance are rated to have maximum of 10% variance.

      What it does to the sound? That depends where the resistor is. If it is part of high pass or low pass filter, that kind of variance could easily change the frequency response. That 50K is forming a high pass filter with that 220uF cap, so changing that to 47K would mean that your high frequency response changes. (sorry. i'm not going to calculate how much..:))

      Probably the simplest explanation to low/high pass filters i found in this document: http://www.generalguitargadgets.com/richardo/distortion/index.html

      Anyway, that kind of changes to the values won't change the effect too dramatically. With more (or less) high (or low) frequencies coming out, you can just say that you modded it to suit your needs :)

      If i've written something way off, someone please correct me. I've been doing this for only six months, and some of my "knowledge" is still based on assumptions... :)
      +m

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    2. Thanks for your response mate, it all sounds good to me. I keep track of all the parts I have in a big Excel workbook, and I've included a couple of worksheets in there which will automatically do certain useful calculations for you like filters, parallel components, voltage dividers etc, things like that. I'll put up a new guide at some point and include a copy of the calc worksheets so that others can download and use them if they feel they're useful.

      One thing that I will add is that people should never get hung up too much on something like resistor accuracy being all important. In some cases that is definitely the case, such as voltage dividers where you want to be able to predict accurately what voltage you'll get, and for that 1% metal film are excellent. But where resistors are being used in the signal path or in filters who's to say that a bang on 100K will give you the best results to your ears? 100K is only used in the first place because it's a standard resistor value, but that doesn't mean that an old drifted 115K carbon resistor won't end up making the effect sound much better to you just because the extra resistance in that particular location hits a sweet spot.

      That's why I've got a good selection of different types of resistors from MF25 carbon and metal film, to brand new highly regarded and accurate Dale metal film, to old drifted 1970s carbon comps. Sometimes E12 values in a one off build (where you don't have to consider or even care about easily repeatable results) aren't going to provide the values to get the best out of a circuit to your ears, with your gear.

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    3. Personally, i'm using mostly generic 1% metal film resistors. These need to be measured before soldering on, because there may be faulty ones. I still have some 5% in stock, but since the price difference is next to nothing (1 cents against 1,2 cents a piece), i'm sticking with those 1% generic metal film ones. Like Mark said, 1% is tight enough for reproducing same thing over and over.

      Here you can find out more about E12, E24 and other standard values:
      http://www.logwell.com/tech/components/resistor_values.html

      I like those Dale military graded ones, but they are a bit expensive for my taste.. I've ordered a few values in these for special purposes (like woolly mammoth's 4K99), but like in this case, i'd probably get "close enough" results even with 4K7 carbon film.
      +m

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    4. Yes you could definitely get close enough, and it may even sound better. Like I mentioned, who's to say that 4K7 doesn't sound better in that position to you with your gear?

      Everyone should play about with values like that sometimes when they get chance. Using the resistor you mention as an example which is part of a filter, try a 3K9, 2K7 or a 6K8. If you can't hear much of a difference then you know that getting exactly a 4K99 would be unnecessary. If you can hear a difference, which one did you think either sounded, or made the EQ control react best. I bet that you don't choose the original value more often than you may think.

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    5. Thank you guys....
      And i started something here, didn't i?

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  18. I bought some 1N5401 diodes specifically for this, just got them in the mail, these things are huge. the leads are so fat they dont fit in the vero board holes and i had to drill larger spots. Definitely going to be using a 1N4001 instead the next time building one of these buffers.

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    1. Yes I think that makes sense. I think Pete must have got a cheap batch of the 1N5401's which he's used ever since but it is just for reverse polarity protection so there's nothing wrong with using a 1N4001 instead.

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  19. This thing is actually fantastic on bass. It gets rid of that 200hz wooliness, which often leads to the room "swallowing up" your signal. Even with Nichicon Muse caps, this cost me $2.50 to build. That's a lot better than $250.

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  20. just thought i could share how i used this buffer :)
    https://dl.dropbox.com/u/2828668/vpjr%20mod/index.html

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    1. Nice job Jimmie, looks very cool

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  21. Hello, sorry I'm a noob but where do i solder the sleeve of the output jack to the circuit?

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    1. Input and output sleeves are both connected to ground.

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  22. IvIark, will this fit into one of those tiny 2"x2" tap tempo enclosures?

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    1. Yes that should be easy enough. I fitted an opamp buffer in a 2" x 1.5" box and this layout isn't too much bigger, so it should go in easy. You'll probably have to put the DC adapter north, input west, output east and stick the buffer board to the south side so they don't interfere with each other though, like this:

      http://i76.photobucket.com/albums/j6/IvIark_2006/DIY/Mark%20Builds/MB2.jpg

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    2. awesome! hopefully this will bring my bass to life a bit more. maybe I can even scrap my sansamp

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    3. Nooooo! It's always input east, output west... :D
      +m

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    4. Hi.
      Firstly, great blog, and brilliant layouts!

      I want to make two of these buffers, but want to put both in one, 4 1/2" x 2 1/2" enclosure, as a space saving venture.

      Can I run both from the one 9v dc connector or, would each unit need their own?

      Cheers, Paul.

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    5. Thanks for that, and yes there's no problem doing that, just daisy chain the supply wire and grounds from one board to the next. The 100R in series with the supply offers some isolation and each will have their own ps filter cap.

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    6. Great!
      Thanks for the quick reply too!!

      Cheers, Paul,

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  23. I put this on my board in front of everything, and it seemed to make it sound just a touch fuller. Should I change any values to use it with bass? I'd like to squeeze a little more low end out of it if possible. I use an active bass too, if that matters. Also would it be better to try it somewhere else? I was thinking maybe put one in my amp's effects loop and one at the input of the board, since I run the board in front.

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    1. I can't see any filter in there that would cut bass guitar frequencies so I'd just give it a try as it is.

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  24. Hi, Just wondering what schematic you based this on. I haven't found any with the D1 Diode in it.

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    1. http://i76.photobucket.com/albums/j6/IvIark_2006/Layouts/Schematics/CornishG2InputBuffer.gif

      The only other versions I've seen of the schematic didn't show any power components at all, only the buffer circuit. With Pete's reputation for being thorough, he'd be unlikely to omit reverse polarity protection from any of his pedals.

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    2. Excellent, thank you. I built the buffer. It is my first build ever. I thought it was working...but now I'm not so sure. When I unplugged the buffer from the power supply I didn't lose my signal. My guitar was still coming through. I'm guessing this shouldn't be the case.

      Here's a photo of the buffer... http://db.tt/WNiV5Ffg

      The sleeve of both the input and output are going to the negative ground.

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    3. I also used a 2N3904 instead of the BC549, and I used a 1N5408 instead of the 1N5401. If this matters at all in terms of polarity or anything.

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    4. My God those diodes are ridiculous! I bought some specifically for Cornish pedals and didn't notice how big they were when I threw them in my diode box, but I'll probably use something else based on that pic. :o) Are you sure the leads of the diode are separate from the 220u cap leads by the way?

      If you look at it, this is one of those circuits that could pass signal unplugged because there is a passive path through the buffer. Are you using it in a chain of effects or testing it on its own? With no other buffer or buffered pedal in line, put it at the front of a long line of true bypass pedals with patch cables between them all, and I would be amazed if you could hear no difference between the plugged and unplugged sound. Unplugged it isn't acting as a buffer, it's just a bunch of passive components in the signal path. Plugged in it provides the low impedance output you want from a buffer which could drive a long chain (and cable) to the amp.

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    5. If you used a 2N3904 did you rotate it 180 degrees because the pinouts are the reverse of the BC549. And ha, that explains the huge diode! :o)

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    6. I couldn't see the transistor properly in your pic, but looking closer you haven't. Turn it round the other way and you should be good to go.

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    7. I'm fairly certain once I rotate the 2N3904 it will solve my problem. I just installed it the way it is drawn in the diagram. Honestly, I barely know what I'm doing. I'll repost tomorrow once I've had a chance to switch it.

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  25. Great layout! I would like to ask to which tracks the 220uf elco is connected? I'm not sure if I understand the image correctly.

    Tx, Harry

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    1. The top row and the 4th next to Q1 collector. The other dots that you can see in the cap's body are the standard layout of electros with DIY Layout Creator, and are supposed to represent the pitch of the capacitor. I may edit the source of the electrolytics in the software's library to remove them though because a couple of people have found that confusing now.

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    2. That indeed clarifies why it didn't work. I started this circuit as my first vero board circuit and created it fully mirrored. ;-) I ended up connecting row 3 and 4 of the 220uf cap on one side which is why it sounded so dull probably. Didn't do much in any case. LOL.
      Will rebuild this one again because I'm eager to find out how it sounds compared to other buffers I'm trying out,

      Thanks for providing these great circuits!

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    3. I haven't been lucky yet with this one. I've tried with an audio probe to detect where the input/output signal stop and my multi meter measuring voltage.
      I only get a very tiny bit of signal and I've tried a BC549 and a 2n5088 with minding the orientation. The output signal somehow dies at the 120k resistor going to the base, this is where it connects with the input too of course. From full to very low and tinny sounding.
      I will first start breadboarding this to see if I can find the issue.

      BTW, I read 9v on the collector and 5v on the base. Is that correct? So the VB on the schematic is 9v and the 120k and 200k voltage dividers result in 5v.

      Not sure what else to check? I verified that the transistors are working.

      Positive side is that I learn from doing it wrong. :D

      Thanks!

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    4. Post a high res front and back pic of the board

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    5. Sorry, already took it apart. I will build it up again to see what's wrong.

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    6. If you're using the same components check them with a DMM before soldering because oneor more may have been damaged by the heat of soldering/desoldering causing the issues.

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    7. I've breadboarded the circuit and it's working now with the old components. I've ordered some new ones because I had to extent the legs of the components which is not working nicely when used in the vero board version.
      When I was bread boarding I was thinking that it would be great to have a tutorial in how to convert a scheme to a bread or vero board version. I noticed for instance that the order of components (say caps and resistors) is not always identical to the scheme, so which rules apply would be handy,
      Also n the tutorial it would be nice how you could build only a part of a circuit in a working state. This way it's easier to build up the end result module wise and prevent mistakes on bigger circuits.

      Just some ideas. Lemme know what you think.

      Harry

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  26. I finally had the time to solder this circuit again and it's working correctly now. I've tried a BC549B and BC549C where the latter has a higher HFE (the ones I had were 470 and 640). The BC549B was about 305 which sounded much better to my ears than the BC549C. The C somehow lacked the sparkle the B version has. Not sure why this is but it seems this circuit is more based on lower HFE transistors?

    Thanks for the layout!

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  27. A quick question to any that have made this....
    I've just finished my first (of two) and, while it clears up my tone brilliantly, it also creates a huge volume drop.

    Anyone with similar outcomes?

    Cheers, Paul.

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    2. Well all the values are shown in the layout. Use metal film resistors, electrolytic caps for the 4u7, 22u and 220u, polyester film cap for the 100n, ceramic cap for the 1n and you can use a 1N4001 instead of the 1N5401. It's just for reverse polarity protection for the supply and so has no affect on the sound at all.

      I don't know what brands Cornish uses but it really doesn't matter with something like this. He wouldn't use expensive mojo components for a unity gain buffer and if you use the types listed above you'll be able to make something that is a sonic match of the original. All the parts should be readily available from any electronics store.

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  29. I currently have in issue with this buffer. I use it at the front of my chain and have a Wampler Sovereign Distortion pedal somewhere at the end. The Sovereign started choking (signal cut out for a split second) when playing with a guitar with a high output bridge humbucker while really diggin in the low strings. I have done a demo for the Sovereign Distortion with the same guitar and I never had this issue.
    So I just played the Sovereign straight into the amp with my guitar only. No issue there.
    I added the buffer in front and the issue is there again!
    Another test I did was put the buffer after the Sovereign. No issue again.

    So what causes the Cornish buffer to choke on high output pickups and can I do something to fix it?

    Thanks!

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    1. Harry,
      I had a similar reaction with a high gain pedal also.
      The buffer seemed to work fine with all my pedals except just this one particular one.
      Any ideas IvIark?

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    2. It can happen. A buffer may colour the tone in a pleasing way, but ultimately its job is to convert a high impedance signal to low impedance, and some pedals following just don't like it whether it's a Cornish buffer or a generic opamp buffer performing the task. You just need to experiment and either have some sort of switching arrangement where the buffer can be disabled when you use the affected pedal, or put the buffer after them.

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    3. Thanks IvIark.
      It's clearly a mis-match with certain pedals.
      I've just noticed that, the non obliging pedal, when run with the buffer, half turns itself on, ie; the led is dimly lit when off....
      Odd.

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    4. Hey Paul and Mark,

      Thanks a lot for your replies! I have tried it with 3 different buffers now (Cornish, Klon opamp buffer and a 2n545 based buffer). All buffers in front of the Sovereign distortion and the Tweed 57 cause the same issue. I will need to set both pedals in front of my first buffer to fix this like I've done with my fuzz face pedals. It's a bit of a shame because there will be a slight tone loss by the cables in front of the buffer but that's not too bad.

      I will have a look to build a looper like the Octaswitch to have the pedals in loops and a switchable buffer. :D
      BTW, a schematic for an Octaswitch with the 8 pole dipswitches would be very cool Mark! :D:D

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    5. I meant a 2n5457 based buffer.

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  30. after reading some of the 'rave' reviews here, i decided to build one of these today. i find it to be an extremely nice buffer with no gain loss or tonal changes, but if you're looking for a tonal change, i'd look elsewhere. i think that if it is changing your tone ( i.e. fuller, more 'body' or top end), then either you're running cables that are too long, of poor quality, or your pickups may have an issue. all it does is what it's supposed to do, i.e., turn a high impedance signal into a lower impedance one.

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  31. Does anyone knows a way of wiring it in combination with a booster pedal?It is a small vero so it can fit in with a booster. But I don't know how to wire this.

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    1. Do you want them together or do you want to be able to select either the buffer or a booster? If you want buffer > booster permanently just take the output of the buffer to the input of the booster of your choice to make one bigger circuit.

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    2. Hmmm I didn't explain well sorry...I want the buffer always on and the switch to control only the booster.

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    3. If the buffer is being used for bypass then you only need a SPDT stomp, or DPDT if you want LED indication. The input sockets connects directly to the input of the buffer and then:

      Stomp lug 1 connects to the output of the buffer and the input of the booster
      Stomp lug 2 connects directly to the output socket
      Stomp lug 3 connects to the output of the booster

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    4. I am thinking of that: instead of wiring the cable from the input jack(tip) to the switch(pin 9), I will try to wire the tip to the buffer input and then the buffer output to pin 9 (?)

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    5. You're over complicating it by trying to implement the true bypass wiring for a buffered effect. You don't need to do that. You can of course use a 3PDT stomp if that's what you've got in but you only need to use two of the poles, one for the LED and the other as outlined above.

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  32. Hello,
    will a PNP silicon transistor work? I have a bunch of them and no NPN right now...
    Thank you Mark, I'm a big fan of your website.

    Vincenzo

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    1. Basically yes - you'll need -9V supply and reverse all electrolytics. For -9V you'll need to make it as positive ground or use voltage inverter with ICL7660 - I think it'll be easier and cheaper to order a bunch of 2N3904s :)
      +m

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  33. Hi guys,
    do you understand the purpose of the 1nF and 4.7uF capacitors in this circuit?
    Common collector designs usually don't have these...maybe that's the secret...
    Thanks,
    LC

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  34. Thanks for your answer Miro! I just found a couple of BC549 into my mess. Time for cleaning up my work bench haha!
    Built this into a crappy tone sucking plastic made volume pedal (Bepesco) and it sounds totally awesome. Now I loose some high end if I play without the volume pedal! Everyone with more than 4 pedals should own at least one of these. My clean tone sounds perfect.

    This is my second vero build from a tagboardeffects layout, thank you, you made vero way easier to me.

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  35. Hi,
    I've been trying to do a double one in the same pedal using a -9vDC.
    It sounds really different than a single standard one. it sounds like no buffers at all.
    I've put two buffers in a single box. Each of the buffers is connected individually on its own to an input/output. they just share the same 9vDC.

    any thoughts why?

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    1. Hi! I've heard/read that buffer do not like being daisy chained but only because it creates unwanted noise in the circuit. Never heard of something like this.

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  36. I think I have built this properly, and have triple checked my component values and placement...but I am still getting a very weak signal through the buffer. Any suggestions?

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    1. Did you socket the transistor?

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    2. No, I soldered it directly to the board.

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    3. What voltages do you get on the tranny?

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  37. Wait, have I not woken up properly or is D1 reversed?

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    1. No it's right, it's a parallel reverse polarity protection diode. It should also have a fuse in series with the 9V line (and I'm sure Cornish will include this even if virtually all other builders omit it), and so under reverse polarity the fuse will blow (or the diode will if you omit the fuse).

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  38. Hello and thanks for this great idea. But I have a problem : I built 3 of them, all properly checked and all of them with high-grade components (Styroflex and MKP capacitors, Elna Simic electrolytic capacitors, 1% metal-film resistors, Mogami cable...), but all of them have a noticeable white noise when I raise the volume in clean mode and the guitar is connected. And the white noise is even more noticeable when in front of an overdrive. Without the buffer the noise disappears. The buffer is connected to a 1 Spot regulated power supply. Thank you very much.

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  39. Hi, I got it working, but with the 200k switched to a 220k and the 7k5 to a 8k2 due to sourcing reasons, it is not unity gain.

    I tried to swap a 180k for the 200k and a 6k8 for the 7k5, instead, but that doesn't work at all, it just makes the buffer prone to clipping.

    Is it reasonable to expect unity at all, and if it is, which resistors should I adjust?

    Thanks in advance

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    Replies
    1. This buffer is an emitter follower which by its very nature is always very slightly lower than unity, you can't make it boost. It should be very close though and most probably imperceptible. Check for other potential causes such as cold joints.

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    2. Mark, thank you once again. It appears I'll be checking my components before soldering from now on (yeah, I know, I know). My 50K resistor to ground from output was actually ja 50 ohm one. No wonder the output was somewhat lacking :)

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  40. Works even with the lid closed :)

    Fit it into a 52,5x38x31mm case, just.

    https://fbcdn-sphotos-e-a.akamaihd.net/hphotos-ak-prn1/6685_10151533026629617_900975043_n.jpg

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  41. Hey, just getting started here, thanks for all the work you guys are putting into this. Quick question, will this or the Klon buffer fit well in a 1590A enclosure? This is gonna be my first build... Any cautions/suggestions?

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    Replies
    1. Ok, just noticed the post before this one, that's a tight package, maybe too tight for a first timer like me... Any other recommendations on enclosures for this one...

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  42. What does the 10m resistor do? I didn't have any when i built it and forgot all about it. Then I boxed it up and it sounds great. Was that resistor necessary? Can I substitute it? Thanks for all the help! Your site is amazing!

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    Replies
    1. It's just a pulldown resistor, if you're not getting any pops when switching then don't worry about it, but you can sub it for any value 1M or above

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  43. I made this buffer several months ago, but I didn't use it.

    After checking my cables, I noticed huge treble loss so I decided to finally try this and I was amazed - what a difference. I have many pedals on my board and many cables, but sound is now clear and guitar sounds to my ears the same as plugged directly to amp. This is really great buffer and great layout.

    I placed it in my wah because it is first pedal in chain. Wah does not sound good after this buffer so I wired it after wah effect, just before output jack, it sounds great that way.

    Thanks one more for great layouts.

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  44. I wonder why this thing gives me hum with power supply?

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  45. I noticed other schematics of the Cornish Buffer have the 150R resistor listed as 51R. This is the only Schematic/Layout that I can find with the 150R. Is this the correct value or a Type-0?

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  46. Does this have the RF filter or is it just the buffer? I'm thinking I could use a little of both in my pedal chain.

    Thanks in advance!

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  47. Is there some way to hook up an led to this without having to install a switch?

    ReplyDelete
    Replies
    1. Would I just sent the negative side of the led to ground.

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  48. This comment has been removed by the author.

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  49. I´m new to this, and wanted to ask a question. First of all, sorry for my english, I´m from Spain. I have the next setup:

    Ibanez JS-100->Morley Bad Horsie->Lovepedal Eternity Clon->Bogner Alchemist

    Bogner Send->Boss GT-6->Bogner Return

    The GT-6 sucks a lot of tone when Bypass (like CryBaby did), will this buffer set behind the GT-6 before de return help?

    Thanks for all the work you do for this site, it´s amazing. Cheers from Spain.

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  50. because in your scheme has 51R? as some found on the net.
    and the addition of the 50k also, why?
    grateful

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  51. Hey!
    If I add a mini toggle switch, what should i get, and how should i wire it? Thanks

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    Replies
    1. Oh man, I was just talking about this with a buddy. Weird! Use a mini DPDT switch (on-on) and wire it exactly like the right two columns of the 3PDT switch Mark shows on the "offboard" wiring page.

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  52. Hey guys. I wonder if anyone can help me understanding how to wire this with a DPDT switch to bypass/engage the buffer but also with an LED? Thanks a lot!

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    Replies
    1. The LED would be to indicate when the buffer circuit is ON, in case that wasn't clear. Any tips?

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    2. You can't do it with a DPDT switch unless you use millennium bypass like this:

      http://i76.photobucket.com/albums/j6/IvIark_2006/DIY/MilleniumBypass2.png

      Are you doing it with a stomp switch? I would normally use a toggle switch with a buffer because I'm unlikely to ever want to turn it on or off mid-song, so it's likely to me an always (or at least almost always) on effect. If you use a toggle the LED isn't so important because the position of the toggle will indicate it's state, but if you do want to doit with just a DPDT switch of some description you'll need to use the millennium bypass layout linked above.

      If you use a 3PDT stomp you can use the normal offboard wiring layout shown here:

      http://tagboardeffects.blogspot.com/2012/02/offboard-wiring.html

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    3. Thanks for confirming that, IvIark. I wasn't sure whether I was missing something and perhaps it could be done. And yeah, I am going to use a toggle switch, not a footswitch.

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  53. Stupid question I guess, which 549 should I be using I have a 549b and 549c

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    Replies
    1. Either, it doesn't matter. The buffer is unity gain so higher hfe won't make any difference.

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    2. Well. It is a buffer, so the hFE of the transistor doesn't matter on this one. The difference between B and C are the hFE gain ranges. But you should probably buy 549Cs, because those will come handy for other builds like Big Muffs.
      +m

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  54. Cheers guys, don't quite grok hfe's yet, working on that though.

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  55. I wonder if you guys could help. I've built a few pedals before but somehow I'm having a problem getting this one (which should've been the easiest?!) to work correctly.

    Basically, I get signal through the circuit (although around -6dB quieter than the bypass signal) provided I don't connect a ground connection to the board. As soon as I connect the ground, the signal disappears and I only get a small amount of noise.

    Pics of the board: https://drive.google.com/folderview?id=0B5zYI2n4nmX9R0lTa0xLOTVONkk&usp=sharing

    Any help is much appreciated!

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  56. Hey Saulo, looks like the 100R needs a bit more solder reflowed on the row to the collector, and some at the base connection might help too.(Maybe take the transistor out first)

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  57. Ha, you nailed it, Benno! All working now. I'd removed the solder there when troubleshooting it and then completely forgot to redo it so thanks very much for the extra pair of eyes.

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  58. This comment has been removed by the author.

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  59. Hello Ivlark, the r8(150r)? I found there looking layout with the value of 51r? that would be ideal? thank you very much!

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    Replies
    1. I've seen a layout where it is 150R, one where it is 51R and even higher values when used directly into the first stage of the G2. With the low values it really won't make any difference at all.

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    2. R8 is 51R and when the effect which is included is bypassed then the 51R goes to output Jack via an 91R resistor so 51+91R =142 R are close to the 150R used when buffer used as a standalone buffer , by the way if the buffer is placed in front of the effect then the 50K resistor from output to ground should go as well to the output jack too and not on the board so when the effect is engaged the 50K resistor is in the output and not in front of the effect , like this way works on G-2 .

      I repeat when buffer is standalone buffer 91R goes with 51R and is 150R and also with the 50K both are included on the board like the vero here.

      Analog Design Pedals Greece

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  60. Here is my Cornish Buffer. I built it into a tiny black 1590lb box. It's the one on the right of the photo. It fits great under a Pedaltrain Mini as you can see. And here it is next to some others.

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  61. Built 2 into a 1590B. One wired for board input and one for board output. Put a DPDT switch inline with both so they can be bypassed. Did that simply to hear the difference they make rather than any notions of bypassing for particular pedals, although that may come in handy at some point!

    Mounted the box under my PT-2 and patched both to the start and end of my fx chain. This makes a convenient patch panel for the entire board as both my guitar and amp cable now plug in on the same side and that will help keep a tidy/safe stage.

    There is definitely a difference in tone. Top end sparkle and a more 3D like (no so undefined mids) sound. Switching them in and out resulted in my experience of the following....

    Its pointless having one at each end of your board. I run 6 TB pedals and 3 Boss buffered ones. Buffer at the start only sounded the best IMO. Buffer at the end was more subtle. Both on I couldn't hear much of a difference from having one at the start only. This may be a different story with your rig or even the size of your board may play its part. YMMV.

    I'm having a somewhat love/hate relationship with it. I play a strat into a twin reverb in a wedding band so I have to cover lots of different genres. I've found that for some of the rock tunes (AD/DC, Status Quo etc) my rhythm sounded fine but my solos were borderline shrill or piercing. TBH I don't really think I actually needed one at all now. Or maybe I have to play with my settings everywhere else and get used to what this buffer does. The other side of that coin is that for the clean funky stuff its great!

    Anyway...hope this helps some people and cheers for the layouts!

    Ciaran

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    Replies
    1. Yes the problem you're having is that you've made allowances at the amp for the treble loss you were experiencing without the buffer, so those settings will need tweaking to accommodate it. I agree it can become one of those situations where you may not really need one and you're happy with your sound as it is, rather than use one and having to tweak the EQ on your amp to try to make it sound more like it used to :o) I have a couple of buffers built, but don't use them in my usual chain for that very reason. But then I'm a bedroom player now, maybe that would change if I was also having to make allowances for a couple of 20+ foot cables.

      The one thing that will still make a buffer attractive to a lot of people is that once you have tweaked your amp to accommodate it, you should get consistent tone from then on no matter what pedals you change in your effect chain.

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  62. Hi - not sure if this is the right place to ask, but here goes. I want to build a buffered splitter (basically exactly like the JHS one). Would there be any problems using this one and just hooking ot up to two different outputs?

    ReplyDelete
    Replies
    1. Yes, there would :) If you simply split the output of this buffer, the impedance differences between the two different devices (what you hook up to the outputs) will cause the signal to choose only one of those paths.

      You'll need a splitter circuit, not only a buffer. Or you could build two of these and take the incoming signal to both circuit's inputs. This way you'll even out the impedance difference, because the two buffer circuit inputs are identical.

      As it seems we're missing a splitter from the library, i may post a layout for AMZ-style buffer/splitter soon. Not tonight, since i've been tinkering with effects for 16 hours straight. And i need to sleep too...
      +m

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  63. Right that makes perfect sense. Thanks miro. I just took a look at the AMZ splitter you mentioned and I guess I will just build that instead. But just to make sure, the outputs on the layout seem completely modular, so if I only want a two output device, I can just leave out columns 14-18, right? http://www.muzique.com/lab/splitter.htm

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    Replies
    1. Yes. I've drawn 2 channel version of it about a year ago. There just hasn't been a lot interest for it :) I'll post it right now.
      +m

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    2. There you go.
      http://tagboardeffects.blogspot.fi/2014/08/amz-2-channel-splitter.html
      +m

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    3. Yeah, I guess Im just weird like that:-) No, seriously, I've recently using a two amp setup which sounds cool in itself. But I'd like to split the signal just before my delays, so that I have dirt and whatnot from one amp and delays from the other. The sound becomes much more focused that way.

      Check out this video: 10:50 when he kicks in the fuzz

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    4. Perhaps it works better with the actual link... http://youtu.be/zXiJ-Tw8WN4

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