So we have:
IC vero using TL071
IC perf using TL071
JFET basic buffer
JFET buffer with voltage divider for increased headroom.
Looking at the differences in sizes I'd be tempted to try the basic JFET buffer first, because if that does the job well enough it's so small that it should be easy to fit in any effect's box with the minimum fuss.
Looks like I'll be trying out the basic JFET in my volume pedal. Any thoughts on how to incorporate it in?
ReplyDeleteThanks! I'll try out the fourth one to see if it cures my squealing OCD build. For those who want more information on these (and other) buffers by Jack Orman, here is a link:
ReplyDeletehttp://www.muzique.com/lab/buffers.htm
I built buffer number one and buffer number four last night and they both work fine (how could they not being simple circuits?). However, they didn't cure the OCD squealing.
ReplyDeleteIn my tests, I discovered that the BOSS TU-2's buffer seemed to tame the squealing. There is a schematic of the TU-2 online, and it looks like the buffered bypass is an FET buffer at the input followed by a BJT buffer at the output. Maybe that's the magic? I may try building the Klon buffer eventually and see if that does the trick.
Very interesting. I knew a version with two resistors, 1M or 2M both, but it wasn't impressive.
ReplyDeleteMust try this one.
Is there possibility to have a vero with gain and/or tone control?
Thanks
BTW: verified TL071 is verified and sound very good and transparent ;)
DeleteHi Guys, I put #3 in a guitar after the PU select switch and before the vol pot. The middle PU has a coil select switch that pops when switching coils. I like the sound- I used a J201 instead of the 2n5457 for this one as it sounds brighter to me. Where should I put a pull down resistor to silence the popping? 10k, 1m?
DeleteNo way to have a gain control? :(
ReplyDeleteIf it has a gain control it isn't a unity gain buffer
DeleteThe IC perf TL071 seems weird to me... maybe I wrong, but the 1M resistance is not connected properly on the 3rd PIN?
ReplyDeleteIt's just two different configurations, check out the top two opamp buffers shown on the AMZ buffer page: http://www.muzique.com/lab/buffers.htm
DeleteI built Buffer#3 for its compact layout and put it on board my guitar after the pu selector switch and before the vol pot. It sounds great, and is so tiny I just stuck it to the battery w/ double sided tape. Thanks for helping me improve my tone!
ReplyDeleteIs there an alternative for the 2n5457 in the third layout?
ReplyDeleteThanks!
Pretty much any JFET should be ok in a simple unity gain buffer. Just watch the pinouts
DeleteThank you, is a J201 the same pinout?
Deletenot sure, but if you search google for "j201 datasheet" and "2n5457 datasheet" you should find the data sheet for each on the first or second page. just compare to see if they are the same or not. if not you may need to twist the pins or flip the transistor 180 (backwards from how it's shown on the layout) to get it in the right orientation. always consult the datasheet, it's one of the best things that can help you out.
DeleteFor the jfet buffers, can I replace the resistor between the Source and Ground with a trimpot to create a boost?
ReplyDeleteNo. That would be the case, if you took the signal out of Drain, but from Source - that won't work.
Delete+m
This comment has been removed by the author.
ReplyDeletehi, i had a couple of 2n5457's laying around so i built the third layout (verified).
ReplyDeletethe tone of my guitar is back!
i am housing all my pedals under a single box at the cost of low-volume-and-less-treble sound, but not any more.
however my fuzzes are not the same any more, they sound way too harsh than before.
the buffer is placed before the fuzz.
is there a way to control the impedance and make it more fuzz-safe ?
like this guy suggests?
http://screaminfx.com/tech/why-and-when-to-use-a-guitar-buffer-pedal.htm
Hi Guys, I put #3 in a guitar after the PU selector switch and before the vol pot. I like the sound, but there is a pop when I toggle the coil cut selector switch. where should I put a pull down resistor to silence the pop? What value resistor 10k,1m ? Thanks, and always thank you so much for all your time and info
ReplyDelete1M
Deletespent the last 3-4 days and got nothign ..finally got frustrated and just wired the few reamining ic chips up p2p , and they worked, just to make sue I am nt crazy ,..no I dea why these wouldnt turn out ..
ReplyDeleteI have been using the above vero TL071 buffer for some time, but it never felt really transparent to me. I was wondering if it might be worth adding soulsonic's stupidly awesome buffer to the above list: http://www.freestompboxes.org/viewtopic.php?f=13&t=26102 It's a more complex circuit but the difference in transparency is night and day. I posted a somewhat crude but verified vero layout in that thread.
ReplyDeleteI know this is over a year old, but thought you might be interested in just How small I've managed to make 2 of these buffers using PCB and SMD technologies...
ReplyDeleteThe Opamp one is based on the perf, while the JFET one is just the simple version.
http://imgur.com/TDScpqu.png
Fender Medium pick for scale.
-Ryan
Crikey! That IS small. Well done. You get them done at OSH Park? They must have been like, $3 haha.
DeleteNot even! $1.70 for the Opamp buffer PCB, and $0.60 for the JFET one. And that's for THREE OF EACH. And yeah, got them done at OSH Park.
DeleteMaaaaan! Genius. Cheap. I'm impressed. SMD is a little daunting but it's doable huh...
DeleteNice job Ryan. SMD isn't as bad as many people may expect, as long as the board isn't designed around anything daft like the 0603 or 0402 packages. For 0805 or 1206 it's actually really easy. Just tin the pad slightly then line up the components and touch the legs with your iron. That usually give you enough heat to secure it in place and then you can add more solder if you feel the need.
DeleteFor DIY I really couldn't understand why some people ever consider using the smaller (0402 or 0603) packages. There is never a reason to. You could easily fit a Klon or I bet even a huge flanger circuit in a 1590A using the larger 0805 or 1206 size components so what is the point in ever doing it smaller?
Hi, All!
ReplyDeleteWill these circuits reverse the phase of the signal?
The JFET circuit is a source follower and the IC circuit is non-inverting, so in both cases the input and output will be in phase
DeleteThanks for these curcuits!
ReplyDelete#4 in 6x5 http://oi61.tinypic.com/sf9yxw.jpg
Got a Question regarding the JFET version with voltage divider... Shouldn't there be one more 10uf within the voltage divider? E.g. from 7/5 to 6/5 ? Its done like this in http://www.muzique.com/lab/buffers.htm for Vr, which is basically the same...
ReplyDeleteHi,
ReplyDeletewill this cure HM-2 clone from this site? I have build one and it starts to squeal on 85% of treble when gain is at max. Is this a issue that will buffer cure?
Thanks,
Hello, can anyone tell me what the 'red squares' indicate on the diagrams? (Red square filled with white and a red dot in center) Please pardon my ignorance, I'm new to electronics. Thanks for the info!
ReplyDeleteIt indicates a place where you have to make a cut on your vero board. Left side has no connection to the right side any more. Can be done by using a simple drill bit.
DeleteThanks Peter, much appreciated!
DeleteOk, so I'd like to build one IC and one jfet buffer from this post (the topmost layout and the bottom layout) just to hear the difference. I'm using these as a 'piezo buffer', and I've noticed that a lot of the buffers specifically for use with a piezo pickup use a 10m resistor... Can I build the layouts above and just substitute a 10m in place of the 1m?
ReplyDeleteYes
DeleteThis comment has been removed by the author.
ReplyDeleteThis comment has been removed by the author.
Delete(Thanks for the quick reply lvlark) Ok, so I've got the topmost buffer built, (tl071) and I get no sound at all :( I've double checked my layout and it's correct, no visible shorts or anything. I used a 0.1uF 100v capacitor (little grey flat box) for the part marked '100n' and my ic has the #1 leg in the top left corner... I used a 4.7m instead of the 1m shown. I've got the 9v+ wired to the pad marked 9v, and everything grounded to the ground pad. It should work just as is right, I don't need to ground the ground to a metal box? This is my first circuit, thanks for your patience and incredibly cool help.
ReplyDeleteAnyone have an idea of the input and output impedances one these?
ReplyDeleteAll inputs 1Meg except number 2 = 500K. All outputs not worth talking about.
Delete
ReplyDelete254/5000
I built a Vico Vibe tremolo and it has a loss of volume. I put an LPB-1 in the output of the tremolo, but it messes up the sound and changes the drives and fuzzes on the line. Would any of these buffers be the one to compensate for this volume without changing the sound? Thank you.
hello. i was trying to use different buffers in a box with a "true bypass" switch (different ways of true bypass wyring). and i always hear "pops" when i turn it on. how to fix it?
ReplyDeleteHow much headroom is lost when using the JFET basic buffer instead of the JFET buffer with voltage divider?
ReplyDeleteIn theory it should allow a hotter signal before you get clipping but I honestly don't think it will matter too much in the majority of cases. If you have particularly hot pickups then it may be useful, but I've never had clipping out of the basic design with single coils and humbuckers I've used. But then for an extra couple of components it's not a big deal to err on the side of caution if you have room for the bigger board.
ReplyDeletewhat i have to do to turn the phase 180 ° with the JFET version so that i have a buffer that inverts the phase?
ReplyDeletesuggestion: this bunch could be labeled verified...
ReplyDeleteperhaps with checkmarks after the 3 verified ones in the OP
I mean, these have long been verified... (except for that tagboard layout...)
I actually think the other layout is verified too so I'll just change the tag. Thanks for the heads up
DeleteA little late to the party here, but if anyone's watching, I have a question. I've built #4 from the layouts in this post, and it works well, but even after multiple builds I see anywhere from 2 to 4 volts on the output when first engaged (but that voltage dissipates over time). I've also built the JHS little black buffer, and it behaves in the same way.
ReplyDeleteAm I doing something wrong, or is it ok for a standalone buffer to show so much DC voltage on the output? ...and if it's ok, why is it ok?
Thanks to all who contribute here; this community is giving me a great education, and a lot of joy in learning and building!
The 10u cap at the output should block DC so it sounds like you may have leaky caps. Have you got any others you can try?
DeleteAfter learning about decoupling and bypass capacitors, that's what I thought too. I've tested by replacing the 10Uf with different brand names, as well as different voltage ratings, with no change. Then I socketed the JFET so that I could replace and test more easily there. I've also completely rebuilt, verifying values and tolerances of each component before install.
DeleteI've tested in the box by connecting a DMM to tip and sleeve of the output jack, as well as out of the box with only power connected and DMM probes to the board. I get similar results from both dedicated power supply (a Joyo JF-18R) and 9v battery power.
Observed voltages at the JFET are:
Drain: ~9 volts.
Source: ~5 volts.
Gate: ~4 volts.
With the latest build of #4, today voltage at the output is ~4 volts when I first power it on (out of the box). It will dissipate over time, but the goal is to get rid of the "thump" if I have to power off/on for any reason after setting up.