Here's a collection of vero (stripboard) and tagboard guitar and bass effect layouts that we have put together covering many classic and popular effects in growing numbers. Many of these have been posted on freestompboxes.org, so check that site out for great discussions on building your own effect pedals. Enjoy the builds and please also visit us on Facebook and Twitter
Here is V.2 of Catalinbread SFT Overdrive.
You can find schematic and extra info on the original FSB's thread here.
09/08/16 Layout updated! Changed Sw6 to Sw4.
Is there a link to the schematic? It works on one switch setting with the other being feedback and oscillation. It is also incredibly dark at all tone settings.
I'd love to add a separate 3pdt and pot to act as a boost side to this, is there a small one knob vol boost circuit I can add in separately as per the off board wiring section?
thanks so much for that, where would the LED for the boost side go to? I have a few builds id like to add a volume boost to so will look at the AMZ as well
also looking again at the offboard section there is a diagram for a switchable boost, the "boost in" and "boost out" wires at the top, would they go to the volume pot?
Think of it as two completely separate circuits in series with each other. No different than turning on 2 pedals on your board. The off board switchable "boost" circuit could be anything...phaser/chorus/compressor etc.
But in your case you want a volume boost. This diagram would put a boost circuit BEFORE your SFT...so it would increase the distortion, not the volume. You would want to put a boost circuit AFTER the SFT for that. So have a look at the Dual Effect example. Spend some time examining both and you'll see they are exactly same, only that the primary circuit (SFT in your case) is either first in series or last.
Boost In/Out refers to the boost circuits In/Out as shown on its layout.
For the two volume pots solution...follow my previous post and add an LED to the 3rd pole just like you can see on the off board page.
I've made the 1st SFT a while back and i love it for both guitar and bass. IMHO it responds great with a booster in front of it to crank it up like an amp. Like Ciaran mentioned, it mainly increases the distortion. FYI, I use a Super Hard On booster.
Today I was telling myself to stop building overdrives, fuzz... (I'm still waiting for partes to build 2 more). Now I realize I need one more :) Forex Enigma Review
How does this compare to the Formula 5? Anyone built both? I was not very impressed by the Formula 5 with 2n5457, eventhough the demos sounded great. These demo's sound great too, but i'm scared it will resemble the formula 5 (which for me meant a compressed overdrive with not a nice grainy texture if that makes sense)
the catalinbread OD pedals are supposed to be based on different amps. with that in mind the formula 5 is a completely different animal since it's based on a different amp. the formula 5 is supposed to be based on an old fender amp, where the sft is supposed to be based on the ampeg svt.
Hahaha welcome to my world, mate! I thought I wont build nothing anymore but today I oredered parts for 3 overdrives and a fuzz... I dont know how could anyone stop this thing.
HI all, built this and sounds brill, I have noticed a couple of issues with other builds this one doesn't seem to have, I build a skreddy mayo and p19 amongst others. Some of my pedals have an audible pop when engaged, is there a way to get rid of this? thanks in advance
I had a the same problem with one of my builds. Read this, it helped me a lot. http://www.muzique.com/lab/pop.htm For me was the LED...I managed to get rid of it using a combination of AMZ true bypass mode (http://www.muzique.com/schem/dpdt.gif) and a small board to delay the LED turn-on (http://www.muzique.com/lab/led.htm). In my case I used the 3º schem. Hope this helps.
awesome thanks man, I'm having one of those days, desperately trying to get my P19 to work but its really quiet, the effect is there but vol is all the way up and sustain all the way up just to be near bypass vol
Is there a link to the schematic? It works on one switch setting with the other being feedback and oscillation. It is also incredibly dark at all tone settings.
I've same problems apparently, I A/B the clone and the original:
- The pedal is really low/dark tuned compared to the original, I think there is a problem on the bass pot, like you can't shut up the bass frequenciens (on the original, on bass at 0, you only get treble)
- There is a switching mode problem, on "stoner mode" in the clone, I get the same the same amount of gain than the "stones mode" on the original, and on the stones, I've clearly less gain.
Me too, now it works better, just the sound it's a little bit different, like 90%, from the original, more low mid thant high mid. Certainly there is a little mistake on it.
I made some progress :) Now the LED works, bypass mode also works like a charm... However, as soon as i switch the Pedal on, it turns silent... I used J111 as JFETs, could they be the wrong ones? My resistance between In & Out varies between around 450kOhm and 750kOhm, depending on the Volume Pot... Is that correct?
Hi, I've built many pedals but this is the first time I can't find why my build is not working. The first second I plug the 9V, the pedal works well but really fast the output is stuttering and volume is lower and lower. In 6-8s there's no output at all. I have to unplug and replug the pedal to hear something again. I tripled-checked the layout, the tracks. I used PN4393 instead of MPF4393. Do you have an idea ?
This is strange. Mine build had exactly the same behaviour. When I plugged it to my testbox the circuit came alive. But after playing a while the sound began stuttering like there was a lose connention on the guitar jack/ cable. But it wasn`t and from then on the volume output got lower and lower. Now with volume and gain maxed the output is below unity (and sounds a kind of shitty). I used MPF4393 and built everything as per layout.
This is strange because I can´t imagine that we both made the same mistake at the same time. Does anybody have an idea where to start debugging?
Clearly looks the switch wiring, the pins are not correct based on "standard switch pin location", look the original schematic to understand how to wire it. I get lot of issues with this thing, now I made 2 of this babes and sounds really great.
I had to check the original layout to understand how to wire the DPDT but I'm sure I'm good on this side.
I have solved the stuttering issue, I had a really tiny almost invisible connection between 2 tracks.
Now I only have a problem with the gain which is continuously lower and lower. In 8 second I have no distortion even if the gain is at max. If I made a connection between the 9V and ground, the gain come back to full but starts again to lower. It looks like I have to reset the pedal :)
Hello all. I have built this and find i have way too much gain when compared to the first SFT in either mode. Is there a problem with the switch or is there a way to mod it for less gain? Thanks.
Hi, someone measured the voltage of the transistors? I built this , but it sounded as if not there is enough power in transistors. I used J113 for the JFETs. Thanks.
Hello all. Been a lurker here for a year & a half now. First time I've had to ask a question I wasn't able to find an answer for somewhere on this wonderful site!
The DPDT: The schematic shows an "ON-OFF" designation. Is there such an animal? I've seen the 3 varieties at Smallbear & Mammoth. The ON-OFF-ON, ON-ON, or the ON-ON-ON variety. Is there an ON-OFF DPDT type switch and is that what is required for this build?
I've seen and used an ON-OFF SPDT type switch but not that type of DPDT. That's why I'm a bit confused and want to make sure I use the right type. The schematic hasn't really helped me figure it out this time.
As always, great site and thank you Alex, Mark, Miro, and all the others. You have taught me much over the last year.
How are you guys numbering the switch? Like this..
1 6 2 5 3 4
Or..
1 4 2 5 3 6
I've got some trouble with my build. Checked for bridges and checked the cuts with a DMM. Double checked component placement and values. Checked wiring. It has to be either bad components, or I've wired the switch wrong? I got some MPF4393's to use with this circuit.. they could be bad I guess?
Can somebody with a working example post voltages please?
Same issues as a few above. Double checked all component values tracks, cuts, links, wiring, etc. Tried various combos of J201, 5457s, 5485s with widely varying results. All controls working properly, just really sound and oscillation with some FETs and settings. Someone please post voltages.
Found an incorrect resistor biasing Q1 and corrected. Working now but had to correct the switch wiring again. It appears as though the last layout revision swapping the 33K to 2K2 the switch wiring was inadvertently mixed up. Should be Sw2 and Sw4 on the left side and Sw5 and Sw3 on the right, top to bottom. Voltages now read:
Hi, with the 2k2 mod it's almost similar to the original, but it's not 100%, in my opinion it's not perfect yet...(maybe i hear this because i tried it only with bass) I tried to wire the switch as you suggested but it oscillated in the 1st position and i had a high pitched feedback kinda sound at the "stoner" setting so i changed the 2 wires back. (I dont know how does it compare to the 1st version, i built that from Sabro's layout and they sound like 2 different animals). If the stones position supposed to sound similar to the 1st version, then they are completely different. This 2nd version has too much gain (compared to the 1st one) in my opinion. I will try to post some drain voltages tomorrow .
Yes, it matches, but O.K., here are my voltages (my supply gives 8,9V):
Q1: 3,6 Q2: 8,9 Q3: 3 Q4: 8,9 Q5: 4,6 Q6: 8,9
I was searching for some demo videos and I came to that conclusion that this pedal sounds like as it should, with the much gain. It completely sounds like in this video: https://www.youtube.com/watch?v=FQMhiv7CigE
Just getting round to having a second go at this. I have redone to board, because I think there was some damage to the first. Thanks for all the voltages that you guys posted, it's really helpful.
Can Alex or another moderator please confirm the switch pinout..
Can anyone advise what the caps are that aren't polarized? I'm guessing the yellows are poly box but not sure whether to use multi layer ceramics or standard or another type for the orange circles on the layout.
Hi, you can use any non-polarized caps that you want really, it's whatever you prefer. When doing the layouts they seem to use the box caps vs the multi layer ceramics more for spacing than sound. For instance the multi-layer ceramics usually have a 2.5mm spacing while the poly-film box caps usually have a 5mm spacing. So as you can see in the layout where space is tight they will go with a ml ceramic, where space permits a poly film box type or even like a Panasonic (if you can source them). I tend to use poly film (either box or Panasonic type) for values from 1nf to 1uf (space permitting), and mlcc for smaller values (in the pf range). Of course anything larger than 1uf would have to be an Electrolytic or tantalum (tantalum's are usually specified). Hope this helps you, Will
I noticed other people that have built this have had issues with the stoner setting where it gives oscillation on the bass pot. Also someone that had an issue where the gain fades away on the stoner setting. Has anyone managed to work out where the issue lies and how to fix this ?
Hi all, I'm hoping someone can help point me in the right direction with debugging this build. I've built it all and the circuit lets the signal through when engaged but the gain is weaker than demos.
The main problem I'm having though is that I get a weird squeal when stoner is engaged. Here's a quick vid to explain better in terms of pots involved:
https://photos.app.goo.gl/1Bwv7Qc03aNyy5g03
Can anyone think where to start with debugging?
DPDT switch is wired lkike this: https://photos.app.goo.gl/d839CmHh40PKJbrE2
Solder on the veroboard looks like this: https://photos.app.goo.gl/Vqg7srdPfQ6kB6a03 https://photos.app.goo.gl/YRxqSaZpcJJ4YAnO2 https://photos.app.goo.gl/O91edceJB54DqYpu1
As far as I can tell the 3pdt switch is fine.
Give me a shout if you need other info that might help.
I have this same problem as Greg. Gain is full but after few seconds is lower and lower. When I sw2 & sw5 put together (only put in and out) is something like reset and effect works fine next few sec. Greg or someone - do you have any solution?
Ceramic caps, or rather the use of them in these projects is really a personal preference. Unless they are the 20% variety. That may be a little too far off of the needed value, then again that might just be the "Mojo" that will make it sound special!
It seems that ceramic caps are often used because of space constraints, or perhaps because of the temperature sensitivity of nearly all other types.
Personally I never use ceramics if I have an alternative, and if I do I only use the mlcc variety of ceramic cap. but truthfully I have never been able to hear much of a difference at all. Even so I think you are correct about 1nf being the limit. I prefer Panasonic's and I use many box cap types as well.
Looking at the schematic at least one of the 4n7 caps is in a critical spot, it is part of the Treble control, or low-pass filter. I would try to avoid a ceramic there, but as I said there may be space constraints. The circuit (vero) board can only be so large to fit in the enclosure ....
Thanks for answering Will! ;) The caps in any of my layouts can be whatever you prefer. I just use those "redish" ones cause they are easier to read when spanning 2 rows instead of the normal 3. Just a question of practicality.
I came back to this after leaving it in my junk pile for almost two years.. the layout is absolutely fine, the way the switch is wired is also fine - no need to alter anything on the layout. The tricky part is getting the JFETs to bias.
Since there are no trim pots and in any case, adding trimpots to force a mismatched bunch of transistors to bias will alter the character of the pedal anyway, you need to buy a bunch of JFETs and plug away until you get between 4-5v on the drains of Q1, Q3 and Q5. Mine does have a touch more distortion than the original, but if I turn the gain pot a little lower than they do in the demo videos it sounds pretty much spot on. It has that SFT character - great pedal in my opinion, and great work by the guys here at tagboardeffects for doing the legwork for us and making the layout - thanks guys.
So, take notes of the voltages as you test different transistors; you will get there eventually. In my experience 2n5458's won't work well.. I never got a reading above 2.5v with 2n5458s. Luckily I managed to score a batch of MPF4393s; there was enough so I could swap them out until it biased up correctly. Good luck guys.
Thanks a lot! I have a problem with my build - it works, but sound sucks, so I've measured drain voltages on Q1, Q3 and Q5 and got 4.5, 2.3 and 5.1 V. I will try to replace Q3 and see what happens.
What about Q2/4/6 - do they have to have some special properties or not?
Hm, I ran out of MPF4323, all of them appear with 2.3-3.0V, so I tried with J202 and the first one I picked from the pile had 4.5V. Pedal works fine at one settings (with switch pins 2 and 3 connected), but when I switch to another (pins 4 and 5 connected, or 22u cap connected to Q5 source), the sound is too prone to microphonic and it has some kind of vibrations.
Was a little reluctant but I finished this. Sounds great with matched Motorola MPF4393 transistors! A little noisy however, and very touchy when you don't play in stoner mode with too much gain but, it's over the top so I get it. It doesn't squeal or anything at all. For those asking still, the switch is really simple to wire up, using this numbering and the layout SW number notations:
Please read my comment below (HGE Contraptions is still me , I only changed the google name for the Blogger in posting):
''HGE Contraptions5 August 2019 at 06:28
Hello Alex/IVIark
For the first time ever in my 120+ pedal building adventure :)) this particular pedal came back from the owner.
There is a clear mistake in the schematic and subsequently, all over the internet and in the vero as well.
If we look at the input, the 470K resistor connected to the first leg of the 100nF capacitor, that should be connected to the second leg of the 100nF! then going to ground as it is.
like so: https://i.imgflip.com/379mgx.jpg
The problem is that it being like that...(it depends on the adapter current,I have 9.71 V), the bias at Q1 will start to drift because it has no reference with the 470K resistor connected like that. It starts to sound strange/and splattered, like a dying battery. As others noticed, if you simply unplug the power and put it back, it ''sounds ok again'', like a ''reset''.
Please correct this in the schematic, it's quite important. With the 470K resistor leg moved 2 rows below from the 100nF upper leg to the lower leg of the 100nF, the bias remains constant and not drifting and so the pedal sounds as it should after 1-2 hours when it used to do this.
I think I have to write this comment everywhere haha.
This is probably going to be my first pedal build, would 2n5485s work in place of the mpf4393s? I know this post is quite old so i hope someone can help me out with this!
Hello Tom, really sorry. Did not try with anything else, and I also matched my MPF4393 (physically selected all to be the same by measuring from what I had). :(
For the first time ever in my 120+ pedal building adventure :)) this particular pedal came back from the owner.
There is a clear mistake in the schematic and subsequently, all over the internet and in the vero as well.
If we look at the input, the 470K resistor connected to the first leg of the 100nF capacitor, that should be connected to the second leg of the 100nF! then going to ground as it is.
like so: https://i.imgflip.com/379mgx.jpg
The problem is that it being like that...(it depends on the adapter current,I have 9.71 V), the bias at Q1 will start to drift because it has no reference with the 470K resistor connected like that. It starts to sound strange/and splattered, like a dying battery. As others noticed, if you simply unplug the power and put it back, it ''sounds ok again'', like a ''reset''.
Please correct this in the schematic, it's quite important. With the 470K resistor leg moved 2 rows below from the 100nF upper leg to the lower leg of the 100nF, the bias remains constant and not drifting and so the pedal sounds as it should after 1-2 hours when it used to do this.
I think I have to write this comment everywhere haha.
Thanks for this pedal! I build it and it works. Just asking myself if it sounds like the original. The drive/ is on the slower/fuzzy side and in stoner mode at full drive there is almost a gate/compression fx after low notes. Is that as it should be? I also moved the 470k resitor to the right place. Could it be the mpf4393s? Thanks!
I built this effect and used 2SK170 JFET (I twisted legs to match DSG topology). Unfortunately I had exactly the same symptoms as other users: dark tone and at Stoner settings sound after 10 seconds of use became splattered and disappeared. Reset (remove and re-plug) restarted pedal but after few seconds situation has repeated. I checked schematics of FSB and layout match it perfectly the same as my vero build. I dig further and found schematics on pedalpcb (https://www.pedalpcb.com/docs/SOFTii.pdf). This schematic is almost the same as on FSB forum with one exception. There is additional 1M resistor that connected Q1 gate to ground. Once I applied this change to vero (it is easy to add on left bottom corner of layout), this pedal became exactly the same as on Youtube videos. First - sound was consistent on Stoner settings all the time, it did not splattered anymore or disappeared. Second: sound stopped to be very dark. It became exactly the same as on Youtube with the same spark. I even checked how Bass and Gain reacts comparing to ProGuitarShop video and it is the same. I highly recommend to add 1M Q1 Gate to GND. I believe that some builders were OK without this resistors perhaps they were forced to match JFETs to somehow make it work, probably some transistors are more prone to connecting gate to ground then others. I tried BF256B, J201, 2SK170, 2N5457 and there were some differences between them without 1M resistors on Q1 gate to gnd, some of them (J201, 2N5457) were very prone to oscillations. Once 1M was applied between GND and Q1 gate, there were not too many differences between transistors, all were pretty consistent.
Hi, i retried this project this week. I redid the Vero. The pedal works, but its does not sound good. The only usable setting is -> Stones -> Bass all the way down, Treble all the way up, Gain at maximum. When I turn up the bass it starts to hum really low, when I engage the Stoner mode, it just is noisy as hell. I did the 1M resitor on Q1 Gate, changed the 470k like described above. I just use J201, and I only have those around. Where should I start?
@HGE Contraptions: I just did my own trace of the SFT V2 and can confirm that the 470k resistor does go on the input as shown, not after the 100n capacitor. There is no gate resistor on the first JFET.
However, the original SFT V2 uses a 470uf filter capacitor, and it turns out this is critical. I originally used 100uf and experienced the bass oscillation everyone's talking about. But after confirming everything else in the earlier trace is correct, I replaced the 100uf capacitor with two 220uF's in parallel and it went away.
So to anyone with the oscillation issue... increase the PSU filter cap, either 2x 220uF or a 470uF, and see if that fixes it.
A couple other minor differences, probably changes in production and not tracing errors: the first two mu-amp stages have 10k resistors in between the source and drain of the two JFETs, while in mine these were 1k, as in the third stage. Also, the bass pot limiting resistor was 10k in mine, compared to 4k7 in the original trace.
The FSB trace was an early unit while mine was later, so I suspect they changed these values along the way and that mine represents the updated circuit.
I just finished building this, and thanks to Alex for the original layout, as well as Iczico and Aion for their posts. Everything works great, though the pedal is absurdly loud! I may follow Ciaran’s suggestion of putting a volume pot on a switch for two preset volumes and no additional circuitry
I wanted to add that there was some serious hum when I engaged the “stoner” switch, which abated when I boxed it up. It’s a really good sounding pedal with a lot of sounds available. If you’re building it, read through the comments above, as well as the documentation for Aion’s version.
One more thing! I used 2n5457s, which work great. I experimented with 2n5458 and 2n5459. The 2n5458 worked in some spots, but I settled on 2n5457 for q1-6.
Noticed a difference between the 2 sides.
ReplyDeleteline 4 to the right, the cut moves one place in the clean cut/link vero.
Thanks. Fixed.
DeleteThis comment has been removed by the author.
ReplyDeleteThanks for this.
ReplyDeleteThanks, I always wanted to try that one out!
ReplyDeleteIs there a link to the schematic? It works on one switch setting with the other being feedback and oscillation. It is also incredibly dark at all tone settings.
ReplyDeletehttp://freestompboxes.org/viewtopic.php?f=7&p=259181#p259181
Deleteoh boy, now this is exciting!
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteWhich would be the best substitutes for the MPF4393s?
ReplyDeleteShould test other JFets (2n5457, J201,..)
DeleteI'd love to add a separate 3pdt and pot to act as a boost side to this, is there a small one knob vol boost circuit I can add in separately as per the off board wiring section?
ReplyDeleteThe AMZ Mini Booster is a great sounding booster, and really simple.
Deletehttp://tagboardeffects.blogspot.hu/2013/01/amz-mini-booster.html
I think the Fulltone Fat Boost was copied and modded from this circuit.
If the circuit has plenty of volume you could just add a switchable volume pot on a DPDT on-on switch (or 3PDT for a Boost LED)
DeleteBoard Vol 3 to Sw2
Boost pot 3 to Sw1
Boost pot 2 to Sw4
Vol pot 3 to Sw3
Vol pot 2 to Sw6
Output from Sw5
This way you can have 2 preset volumes and the tonality shouldn't change....and no extra circuit to add.
thanks so much for that, where would the LED for the boost side go to? I have a few builds id like to add a volume boost to so will look at the AMZ as well
DeleteThis comment has been removed by the author.
ReplyDeletealso looking again at the offboard section there is a diagram for a switchable boost, the "boost in" and "boost out" wires at the top, would they go to the volume pot?
ReplyDeleteThink of it as two completely separate circuits in series with each other. No different than turning on 2 pedals on your board. The off board switchable "boost" circuit could be anything...phaser/chorus/compressor etc.
DeleteBut in your case you want a volume boost. This diagram would put a boost circuit BEFORE your SFT...so it would increase the distortion, not the volume. You would want to put a boost circuit AFTER the SFT for that. So have a look at the Dual Effect example. Spend some time examining both and you'll see they are exactly same, only that the primary circuit (SFT in your case) is either first in series or last.
Boost In/Out refers to the boost circuits In/Out as shown on its layout.
For the two volume pots solution...follow my previous post and add an LED to the 3rd pole just like you can see on the off board page.
cheers man, huge help.
ReplyDeleteI've made the 1st SFT a while back and i love it for both guitar and bass.
ReplyDeleteIMHO it responds great with a booster in front of it to crank it up like an amp. Like Ciaran mentioned, it mainly increases the distortion.
FYI, I use a Super Hard On booster.
This comment has been removed by the author.
ReplyDeleteverified. with an assortment of fets (j201, j111, 2n5458)
ReplyDeletesounds great.
Hi Daniel, does it need any changes or is it just fine as it is?
DeleteI changed only a few values for something close, but everything seems in place.
Deletesome Jfets in Q1 didn't work so well, so it took some playing around.
Thank you, I think I will give it a try after my mpf4393's will arrive.
DeleteThank Daniel!
DeleteIs the switch working properly?
With J201 in Q1 It worked fine.
Deletewith different Jfet i had some oscilations.
And thank you, Alex!
DeleteThe DIY Smart Saw pdf
DeleteToday I was telling myself to stop building overdrives, fuzz... (I'm still waiting for partes to build 2 more). Now I realize I need one more :)
Forex Enigma Review
What transistors did you have in Q2 till Q6 when you had j201 in Q1
DeleteIf I wanted to make the Bass control steeper, I'd need to up the pot value right?
ReplyDeleteHow does this compare to the Formula 5? Anyone built both? I was not very impressed by the Formula 5 with 2n5457, eventhough the demos sounded great.
ReplyDeleteThese demo's sound great too, but i'm scared it will resemble the formula 5 (which for me meant a compressed overdrive with not a nice grainy texture if that makes sense)
the catalinbread OD pedals are supposed to be based on different amps. with that in mind the formula 5 is a completely different animal since it's based on a different amp. the formula 5 is supposed to be based on an old fender amp, where the sft is supposed to be based on the ampeg svt.
DeleteToday I was telling myself to stop building overdrives, fuzz... (I'm still waiting for partes to build 2 more). Now I realize I need one more :)
ReplyDeleteHahaha welcome to my world, mate! I thought I wont build nothing anymore but today I oredered parts for 3 overdrives and a fuzz... I dont know how could anyone stop this thing.
DeleteHI all, built this and sounds brill, I have noticed a couple of issues with other builds this one doesn't seem to have, I build a skreddy mayo and p19 amongst others. Some of my pedals have an audible pop when engaged, is there a way to get rid of this? thanks in advance
ReplyDeleteI had a the same problem with one of my builds.
DeleteRead this, it helped me a lot.
http://www.muzique.com/lab/pop.htm
For me was the LED...I managed to get rid of it using a combination of AMZ true bypass mode (http://www.muzique.com/schem/dpdt.gif) and a small board to delay the LED turn-on (http://www.muzique.com/lab/led.htm). In my case I used the 3º schem.
Hope this helps.
awesome thanks man, I'm having one of those days, desperately trying to get my P19 to work but its really quiet, the effect is there but vol is all the way up and sustain all the way up just to be near bypass vol
DeleteIs there a link to the schematic? It works on one switch setting with the other being feedback and oscillation. It is also incredibly dark at all tone settings.
ReplyDeletehttp://coradar.org/
I've same problems apparently, I A/B the clone and the original:
ReplyDelete- The pedal is really low/dark tuned compared to the original, I think there is a problem on the bass pot, like you can't shut up the bass frequenciens (on the original, on bass at 0, you only get treble)
- There is a switching mode problem, on "stoner mode" in the clone, I get the same the same amount of gain than the "stones mode" on the original, and on the stones, I've clearly less gain.
Just realized the switch numbering on the schematic was wrong.
DeleteI've corrected it.
Me too, now it works better, just the sound it's a little bit different, like 90%, from the original, more low mid thant high mid. Certainly there is a little mistake on it.
DeleteThere could be a value or connection mistake somewhere in the schematic.
DeleteThis comment has been removed by the author.
ReplyDeleteI made some progress :) Now the LED works, bypass mode also works like a charm... However, as soon as i switch the Pedal on, it turns silent... I used J111 as JFETs, could they be the wrong ones?
ReplyDeleteMy resistance between In & Out varies between around 450kOhm and 750kOhm, depending on the Volume Pot... Is that correct?
There is a revision, the 33K resistor is a 2.2K, it will increase the sound. I will try it tomorrow and tell you.
ReplyDeleteOk.
DeleteCool.
Let me know if it improves it!
2K2 is the way!! Now it sounds really like the original :)
DeleteThanks David!
DeleteLayout updated.
This comment has been removed by the author.
ReplyDeleteHi,
ReplyDeleteI've built many pedals but this is the first time I can't find why my build is not working. The first second I plug the 9V, the pedal works well but really fast the output is stuttering and volume is lower and lower. In 6-8s there's no output at all. I have to unplug and replug the pedal to hear something again. I tripled-checked the layout, the tracks. I used PN4393 instead of MPF4393. Do you have an idea ?
This is strange. Mine build had exactly the same behaviour. When I plugged it to my testbox the circuit came alive. But after playing a while the sound began stuttering like there was a lose connention on the guitar jack/ cable. But it wasn`t and from then on the volume output got lower and lower. Now with volume and gain maxed the output is below unity (and sounds a kind of shitty). I used MPF4393 and built everything as per layout.
DeleteThis is strange because I can´t imagine that we both made the same mistake at the same time. Does anybody have an idea where to start debugging?
Any thougts would be appreciated. Thanks.
Clearly looks the switch wiring, the pins are not correct based on "standard switch pin location", look the original schematic to understand how to wire it.
DeleteI get lot of issues with this thing, now I made 2 of this babes and sounds really great.
I had to check the original layout to understand how to wire the DPDT but I'm sure I'm good on this side.
DeleteI have solved the stuttering issue, I had a really tiny almost invisible connection between 2 tracks.
Now I only have a problem with the gain which is continuously lower and lower. In 8 second I have no distortion even if the gain is at max. If I made a connection between the 9V and ground, the gain come back to full but starts again to lower. It looks like I have to reset the pedal :)
In my SFTII schematic this effect have a 470uF not an 100uF, could this be the source of the problem?
DeleteThis comment has been removed by the author.
ReplyDeleteHello all. I have built this and find i have way too much gain when compared to the first SFT in either mode. Is there a problem with the switch or is there a way to mod it for less gain?
ReplyDeleteThanks.
Switch wiring, switch wiring looks the original schematic.
ReplyDeleteChange Sw6 to Sw4.
ReplyDeleteI'll change it on the layout.
Thanks! That did it.
DeleteIt´s a bit noisy and one switch setting has really much gain, but yep, it´s working now. Thanks for that.
DeleteHi, someone measured the voltage of the transistors? I built this , but it sounded as if not there is enough power in transistors. I used J113 for the JFETs. Thanks.
ReplyDeleteHello all. Been a lurker here for a year & a half now. First time I've had to ask a question I wasn't able to find an answer for somewhere on this wonderful site!
ReplyDeleteThe DPDT: The schematic shows an "ON-OFF" designation. Is there such an animal? I've seen the 3 varieties at Smallbear & Mammoth. The ON-OFF-ON, ON-ON, or the ON-ON-ON variety. Is there an ON-OFF DPDT type switch and is that what is required for this build?
I've seen and used an ON-OFF SPDT type switch but not that type of DPDT. That's why I'm a bit confused and want to make sure I use the right type. The schematic hasn't really helped me figure it out this time.
As always, great site and thank you Alex, Mark, Miro, and all the others. You have taught me much over the last year.
You are more than welcome.
DeleteYou need an "On-On" DPDT switch.
Thank you again Alex.
DeleteWill
How are you guys numbering the switch? Like this..
ReplyDelete1 6
2 5
3 4
Or..
1 4
2 5
3 6
I've got some trouble with my build. Checked for bridges and checked the cuts with a DMM. Double checked component placement and values. Checked wiring. It has to be either bad components, or I've wired the switch wrong? I got some MPF4393's to use with this circuit.. they could be bad I guess?
Can somebody with a working example post voltages please?
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ReplyDeleteSame issues as a few above. Double checked all component values tracks, cuts, links, wiring, etc. Tried various combos of J201, 5457s, 5485s with widely varying results. All controls working properly, just really sound and oscillation with some FETs and settings. Someone please post voltages.
ReplyDeleteHaven't seen any voltages from a working version so here's what I'm getting with mine:
ReplyDeleteQ1 .58-1.08
Q2 9.4
Q3 2.5-3.5
Q4 9.4
Q5 5.16-5.45
Q6 9.4
Found an incorrect resistor biasing Q1 and corrected. Working now but had to correct the switch wiring again. It appears as though the last layout revision swapping the 33K to 2K2 the switch wiring was inadvertently mixed up. Should be Sw2 and Sw4 on the left side and Sw5 and Sw3 on the right, top to bottom. Voltages now read:
DeleteQ1 4.8
Q2 9.4
Q3 4.1
Q4 9.4
Q5 5.2
Q6 9.4
Hi, with the 2k2 mod it's almost similar to the original, but it's not 100%, in my opinion it's not perfect yet...(maybe i hear this because i tried it only with bass) I tried to wire the switch as you suggested but it oscillated in the 1st position and i had a high pitched feedback kinda sound at the "stoner" setting so i changed the 2 wires back. (I dont know how does it compare to the 1st version, i built that from Sabro's layout and they sound like 2 different animals). If the stones position supposed to sound similar to the 1st version, then they are completely different. This 2nd version has too much gain (compared to the 1st one) in my opinion. I will try to post some drain voltages tomorrow .
DeleteThe layout switch wiring matches the schematic.
DeleteYes, it matches, but O.K., here are my voltages (my supply gives 8,9V):
DeleteQ1: 3,6
Q2: 8,9
Q3: 3
Q4: 8,9
Q5: 4,6
Q6: 8,9
I was searching for some demo videos and I came to that conclusion that this pedal sounds like as it should, with the much gain. It completely sounds like in this video:
https://www.youtube.com/watch?v=FQMhiv7CigE
Hi,
ReplyDeleteMy switch is:
1-4
2-5
3-6
1 - wire sw4
2,5 - wire sw3
3 - wire sw2
4 - empty
6 - wire sw5
I think it`s the best sounds results.
Voltage:
G - S - D
q1: 6,4 - 8,43 - 5,8
q2: 0 - 4,17 - 4,22
q3: 4,66 - 8,71 - 7,20
q4: 0 - 4,23 - 2,98
q5: 4,28 - 8,85 - 7,90
q6: 0 - 4,24 - 3
I used 2n5457, and q2-J201
Hi guys..
ReplyDeleteJust getting round to having a second go at this. I have redone to board, because I think there was some damage to the first. Thanks for all the voltages that you guys posted, it's really helpful.
Can Alex or another moderator please confirm the switch pinout..
1 4
2 5
3 6
or
1 6
2 5
3 4
Thanks in advance!
Hi! I hope this will help: http://mirosol.kapsi.fi/varasto/boxes_other/pots_switches.png
DeleteWhats the difference within this an the mk 1¿
ReplyDeleteLost with the switch wiring. In schematic it shows
ReplyDelete1 | 2
3 | 4
5 | 6
what is the correct way? I get low pitch noise in the higher gain setting.
Can anyone advise what the caps are that aren't polarized?
ReplyDeleteI'm guessing the yellows are poly box but not sure whether to use multi layer ceramics or standard or another type for the orange circles on the layout.
Cheers
elbee
Hi, you can use any non-polarized caps that you want really, it's whatever you prefer.
DeleteWhen doing the layouts they seem to use the box caps vs the multi layer ceramics more for spacing than sound. For instance the multi-layer ceramics usually have a 2.5mm spacing while the poly-film box caps usually have a 5mm spacing.
So as you can see in the layout where space is tight they will go with a ml ceramic, where space permits a poly film box type or even like a Panasonic (if you can source them).
I tend to use poly film (either box or Panasonic type) for values from 1nf to 1uf (space permitting), and mlcc for smaller values (in the pf range). Of course anything larger than 1uf would have to be an Electrolytic or tantalum (tantalum's are usually specified).
Hope this helps you,
Will
Thanks for the info Will
DeleteI noticed other people that have built this have had issues with the stoner setting where it gives oscillation on the bass pot. Also someone that had an issue where the gain fades away on the stoner setting.
ReplyDeleteHas anyone managed to work out where the issue lies and how to fix this ?
Here's a video clip to demonstrate the problem:
Deletehttps://photos.app.goo.gl/f6Z0eNFXiMpP3jDo1
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DeleteHi all,
ReplyDeleteI'm hoping someone can help point me in the right direction with debugging this build.
I've built it all and the circuit lets the signal through when engaged but the gain is weaker than demos.
The main problem I'm having though is that I get a weird squeal when stoner is engaged. Here's a quick vid to explain better in terms of pots involved:
https://photos.app.goo.gl/1Bwv7Qc03aNyy5g03
Can anyone think where to start with debugging?
DPDT switch is wired lkike this:
https://photos.app.goo.gl/d839CmHh40PKJbrE2
Solder on the veroboard looks like this:
https://photos.app.goo.gl/Vqg7srdPfQ6kB6a03
https://photos.app.goo.gl/YRxqSaZpcJJ4YAnO2
https://photos.app.goo.gl/O91edceJB54DqYpu1
As far as I can tell the 3pdt switch is fine.
Give me a shout if you need other info that might help.
Cheers
Elbee
I have this same problem as Greg. Gain is full but after few seconds is lower and lower. When I sw2 & sw5 put together (only put in and out) is something like reset and effect works fine next few sec. Greg or someone - do you have any solution?
ReplyDeleteSorry for the late answer. I solved the problem by using a 12V power supply instead of 9V.
DeleteThx, but I know what was wrong - switch was broken :(
DeleteThis effect is one of my favorite!
Cheers!
This uses 4n7 ceramic caps? Is that right? I thought you weren't supposed to use ceramics for values over 1n?
ReplyDeleteCeramic caps, or rather the use of them in these projects is really a personal preference. Unless they are the 20% variety. That may be a little too far off of the needed value, then again that might just be the "Mojo" that will make it sound special!
DeleteIt seems that ceramic caps are often used because of space constraints, or perhaps because of the temperature sensitivity of nearly all other types.
Personally I never use ceramics if I have an alternative, and if I do I only use the mlcc variety of ceramic cap. but truthfully I have never been able to hear much of a difference at all. Even so I think you are correct about 1nf being the limit. I prefer Panasonic's and I use many box cap types as well.
Looking at the schematic at least one of the 4n7 caps is in a critical spot, it is part of the Treble control, or low-pass filter. I would try to avoid a ceramic there, but as I said there may be space constraints. The circuit (vero) board can only be so large to fit in the enclosure ....
Good luck and happy building ....
Will
Thanks for answering Will! ;)
DeleteThe caps in any of my layouts can be whatever you prefer.
I just use those "redish" ones cause they are easier to read when spanning 2 rows instead of the normal 3.
Just a question of practicality.
I came back to this after leaving it in my junk pile for almost two years.. the layout is absolutely fine, the way the switch is wired is also fine - no need to alter anything on the layout. The tricky part is getting the JFETs to bias.
ReplyDeleteSince there are no trim pots and in any case, adding trimpots to force a mismatched bunch of transistors to bias will alter the character of the pedal anyway, you need to buy a bunch of JFETs and plug away until you get between 4-5v on the drains of Q1, Q3 and Q5. Mine does have a touch more distortion than the original, but if I turn the gain pot a little lower than they do in the demo videos it sounds pretty much spot on. It has that SFT character - great pedal in my opinion, and great work by the guys here at tagboardeffects for doing the legwork for us and making the layout - thanks guys.
So, take notes of the voltages as you test different transistors; you will get there eventually. In my experience 2n5458's won't work well.. I never got a reading above 2.5v with 2n5458s. Luckily I managed to score a batch of MPF4393s; there was enough so I could swap them out until it biased up correctly. Good luck guys.
Thanks a lot! I have a problem with my build - it works, but sound sucks, so I've measured drain voltages on Q1, Q3 and Q5 and got 4.5, 2.3 and 5.1 V. I will try to replace Q3 and see what happens.
DeleteWhat about Q2/4/6 - do they have to have some special properties or not?
Hm, I ran out of MPF4323, all of them appear with 2.3-3.0V, so I tried with J202 and the first one I picked from the pile had 4.5V. Pedal works fine at one settings (with switch pins 2 and 3 connected), but when I switch to another (pins 4 and 5 connected, or 22u cap connected to Q5 source), the sound is too prone to microphonic and it has some kind of vibrations.
DeleteWas a little reluctant but I finished this. Sounds great with matched Motorola MPF4393 transistors!
ReplyDeleteA little noisy however, and very touchy when you don't play in stoner mode with too much gain but, it's over the top so I get it. It doesn't squeal or anything at all.
For those asking still, the switch is really simple to wire up, using this numbering and the layout SW number notations:
1 |(4)
(2)|(5)
(3)| 6
Here is my built and a youtube sample also:
https://hgecontraptions.blogspot.com/2019/02/hge-contraptions-catalinbread-sft-ii.html
https://www.youtube.com/watch?v=vNEEkHNQ3p0
Please read my comment below (HGE Contraptions is still me , I only changed the google name for the Blogger in posting):
Delete''HGE Contraptions5 August 2019 at 06:28
Hello Alex/IVIark
For the first time ever in my 120+ pedal building adventure :)) this particular pedal came back from the owner.
There is a clear mistake in the schematic and subsequently, all over the internet and in the vero as well.
If we look at the input, the 470K resistor connected to the first leg of the 100nF capacitor, that should be connected to the second leg of the 100nF! then going to ground as it is.
like so: https://i.imgflip.com/379mgx.jpg
The problem is that it being like that...(it depends on the adapter current,I have 9.71 V), the bias at Q1 will start to drift because it has no reference with the 470K resistor connected like that. It starts to sound strange/and splattered, like a dying battery. As others noticed, if you simply unplug the power and put it back, it ''sounds ok again'', like a ''reset''.
Please correct this in the schematic, it's quite important.
With the 470K resistor leg moved 2 rows below from the 100nF upper leg to the lower leg of the 100nF, the bias remains constant and not drifting and so the pedal sounds as it should after 1-2 hours when it used to do this.
I think I have to write this comment everywhere haha.
Thanks guys! Pedals sounds phenomenal.''
This is probably going to be my first pedal build, would 2n5485s work in place of the mpf4393s? I know this post is quite old so i hope someone can help me out with this!
ReplyDeleteHello Tom, really sorry. Did not try with anything else, and I also matched my MPF4393 (physically selected all to be the same by measuring from what I had). :(
DeleteHello Alex/IVIark
ReplyDeleteFor the first time ever in my 120+ pedal building adventure :)) this particular pedal came back from the owner.
There is a clear mistake in the schematic and subsequently, all over the internet and in the vero as well.
If we look at the input, the 470K resistor connected to the first leg of the 100nF capacitor, that should be connected to the second leg of the 100nF! then going to ground as it is.
like so: https://i.imgflip.com/379mgx.jpg
The problem is that it being like that...(it depends on the adapter current,I have 9.71 V), the bias at Q1 will start to drift because it has no reference with the 470K resistor connected like that. It starts to sound strange/and splattered, like a dying battery. As others noticed, if you simply unplug the power and put it back, it ''sounds ok again'', like a ''reset''.
Please correct this in the schematic, it's quite important.
With the 470K resistor leg moved 2 rows below from the 100nF upper leg to the lower leg of the 100nF, the bias remains constant and not drifting and so the pedal sounds as it should after 1-2 hours when it used to do this.
I think I have to write this comment everywhere haha.
Thanks guys! Pedals sounds phenomenal.
Thanks for this pedal! I build it and it works. Just asking myself if it sounds like the original. The drive/ is on the slower/fuzzy side and in stoner mode at full drive there is almost a gate/compression fx after low notes. Is that as it should be? I also moved the 470k resitor to the right place. Could it be the mpf4393s? Thanks!
ReplyDeleteDoes 18v change the drive/fuzz sound significantly?
ReplyDeleteI built this effect and used 2SK170 JFET (I twisted legs to match DSG topology). Unfortunately I had exactly the same symptoms as other users: dark tone and at Stoner settings sound after 10 seconds of use became splattered and disappeared. Reset (remove and re-plug) restarted pedal but after few seconds situation has repeated.
ReplyDeleteI checked schematics of FSB and layout match it perfectly the same as my vero build. I dig further and found schematics on pedalpcb (https://www.pedalpcb.com/docs/SOFTii.pdf). This schematic is almost the same as on FSB forum with one exception. There is additional 1M resistor that connected Q1 gate to ground. Once I applied this change to vero (it is easy to add on left bottom corner of layout), this pedal became exactly the same as on Youtube videos. First - sound was consistent on Stoner settings all the time, it did not splattered anymore or disappeared. Second: sound stopped to be very dark. It became exactly the same as on Youtube with the same spark. I even checked how Bass and Gain reacts comparing to ProGuitarShop video and it is the same.
I highly recommend to add 1M Q1 Gate to GND. I believe that some builders were OK without this resistors perhaps they were forced to match JFETs to somehow make it work, probably some transistors are more prone to connecting gate to ground then others. I tried BF256B, J201, 2SK170, 2N5457 and there were some differences between them without 1M resistors on Q1 gate to gnd, some of them (J201, 2N5457) were very prone to oscillations. Once 1M was applied between GND and Q1 gate, there were not too many differences between transistors, all were pretty consistent.
Hi, i retried this project this week. I redid the Vero. The pedal works, but its does not sound good. The only usable setting is -> Stones -> Bass all the way down, Treble all the way up, Gain at maximum. When I turn up the bass it starts to hum really low, when I engage the Stoner mode, it just is noisy as hell. I did the 1M resitor on Q1 Gate, changed the 470k like described above. I just use J201, and I only have those around. Where should I start?
ReplyDelete@HGE Contraptions: I just did my own trace of the SFT V2 and can confirm that the 470k resistor does go on the input as shown, not after the 100n capacitor. There is no gate resistor on the first JFET.
ReplyDeleteHowever, the original SFT V2 uses a 470uf filter capacitor, and it turns out this is critical. I originally used 100uf and experienced the bass oscillation everyone's talking about. But after confirming everything else in the earlier trace is correct, I replaced the 100uf capacitor with two 220uF's in parallel and it went away.
So to anyone with the oscillation issue... increase the PSU filter cap, either 2x 220uF or a 470uF, and see if that fixes it.
A couple other minor differences, probably changes in production and not tracing errors: the first two mu-amp stages have 10k resistors in between the source and drain of the two JFETs, while in mine these were 1k, as in the third stage. Also, the bass pot limiting resistor was 10k in mine, compared to 4k7 in the original trace.
The FSB trace was an early unit while mine was later, so I suspect they changed these values along the way and that mine represents the updated circuit.
I just finished building this, and thanks to Alex for the original layout, as well as Iczico and Aion for their posts. Everything works great, though the pedal is absurdly loud! I may follow Ciaran’s suggestion of putting a volume pot on a switch for two preset volumes and no additional circuitry
ReplyDeleteI wanted to add that there was some serious hum when I engaged the “stoner” switch, which abated when I boxed it up. It’s a really good sounding pedal with a lot of sounds available. If you’re building it, read through the comments above, as well as the documentation for Aion’s version.
DeleteOne more thing! I used 2n5457s, which work great. I experimented with 2n5458 and 2n5459. The 2n5458 worked in some spots, but I settled on 2n5457 for q1-6.
Delete