The Quantum Mystic Overdrive was developed working closely with Mike Scheidt from the Portland Oregon band, Yob. Mike is known for great tone and groundbreaking music in the metal and doom community. We decided to adapt his favorite pedal from the seminal early YOB records into an updated and upgraded circuit. The Quantum Mystic is an opamp based distortion/OD featuring a 3 band active EQ and germanium clipping. It draws cues from Mike favorite old Grey Distortion, boiled down by a wizard, tweeked, manipulated, upgraded and using both mine and Mike’s ear, we sculpted the form you now hear and feel. Use the active Eq to cut frequencies to represent the old school sounds, or use the EQ to boost the final gain stage to go into the heavily saturated and distorted tones of the future. Dial back the distortion, boost the volume and use the active EQ to find sparkling clear boost tones. Dime it all and get a ball molten lead that propels the Universe Throb. Needing a captivating presentation, we summoned the artwork of another underground legend, Arik Roper. We pulled together something pretty special and I think you all will like this one.
IMO, that thing sounds pretty darn good. i'll have to build it soon.
ReplyDeletetonestack looks fun - http://audioamplifier.web44.net/schematics/
ReplyDeleteHa, I recognise that, virtually identical
DeleteI just built it...and something isent right. Then I turn the volume theres a plenty of sound at 1 oclock, but its very scratchy and ugly (my english is not very good :) I tried to replace the pot, but its exacyly the same, even tried to change the opamps and d1 & d2 with 1n34 and even tried with silicon 4148, but its the same scratchy noise. The tone fades the signal distorts and dies very quickly....
DeleteI think John K is building it so I'm just waiting to hear how his build has gone down. Around that section is true to the schematic and there is something unusual about it IMO, but I don't want to confuse matters by suggesting a modification until the problem is confirmed. Simply because you could have a faulty component and so if John's works ok then we know that the problem must be somewhere other than an issue with the schematic.
DeleteI just finished testing mine and I also had that problem.
ReplyDeletelug 1 of the volume pot should go to VR= (the junction of the two 1M resistors= 1/2 of the supply voltage). also all of the tone controls work backwards so swap lugs 1 & 3 on ALL of them.
IMO, a C1M pot (1 meg reverse audio) works a lot better for the gain control since the linear one has all of it's gain bunched up at the end of it.
Lug 1 of the volume pot goes to ground in the schematic.
DeleteThe thing that I thought looked unusual was no coupling caps between the last two stages which may account for noise
well, IMO, the schematic is wrong then. with lug 1 going to ground, the volume pot is erratic, scratchy, noisy, and the signal fades out. I've seen other circuits that use VR at that part of the circuit.
DeleteYes some do like the Tubescreamer, but VR is just used as a virtual ground to dump the signal. I'm wondering if the omission of the coupling caps is causing the issue then because we know volume 1 to ground is a standard with most effects. But either way, it means one part of the schematic needs correcting and I suppose it's easier to move the volume 1 wire than add two extra caps. Nice one John and thanks for verifying.
DeleteMark, any news or update on this vero? My last build was an erratic gain (works only at the end), and low output.
DeleteI've just been over the schematic and I did spot an error, but only a value. The 10n at pin 2 of IC1 should be 47n, and that will effect the high pass filter at the gain stage opamp channel, but it could also potentially affect the frequencies the gain is applied to which could obviously alter the final sound. That could be the issue so I'd definitely try changing that, but apart from that the layout matches the schematic and so I won't have any more updates unless I see another version of the schematic which may correct errors if they exist in the one I have.
DeleteThank you Mark! Just for report purposes i must say gain is ok with 47n. Output is super low. Mid knob do not act as expected (as a mid boost), but seems just to muffles and drop the volume.
DeleteThough my build is far from perfect (see below), the 10n sounds much better to my ears. 47n turned my build into mud. More bass, but at the expense of a LOT less clarity and bite. I, like many folks into BAT pedals, play doom, so I really like bass heavy guitar tones, and I think the 10n has plenty of bass but allows for more versatility and less of a "neck pickup under a blanket on all settings" kind of sound. Again, could be because my build is a little bit botched, so YMMV. If 47n is on the schematic, then I can't argue with the video demos of this pedal, as they all sounds fantastic with that value cap. Regardless, this cap seems to play a big role in the sound, so it might be worth socketing. Thanks again for the layout Mark!
DeleteWorks perfect now, thanx John! I replaced the gain pot to C1M pot as you suggested and its a lot better. A great distortion!
ReplyDeleteBTW, I found it to have a bit too low of an output so I raised the output on mine X11 by adding just two resistors.
ReplyDeleteBWT, to increase the output, it's easiest just to add another column like this:
Deletehttp://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/BlackArts/QuantumMystic-moreoutput.png
Excelent John! Thank you!
DeleteLooks like lvlark has a 4k7 resistor on gain 3 and you have 47k John. Any reason for the change?
Deletethanks for catching that dumb error. it's now been corrected.
DeleteGround is the same on John´s layout. I tried to build John´s Mod, since it has more output, but mine not work until now. Checking if you guys built this one yet!
DeleteI built this and am getting extremely thin, low output, with only a pretty mild overdrive. All of the pots seem to work as they should. Both diodes read 0.00v on both ends. I can pull them out of the board and the sound doesn't change at all, so I imagine my problem is there, but I can't find a misplaced component, and all of the cuts seem clean. If anyone could think of anything that wold keep these diodes from getting any voltage I'd appreciate it (having trouble tracing the circuit...sorry, still learning). The top IC measures:
ReplyDelete1: 4.12v
2: 3.97v
3: 3.50v
4: 0.00v
5: 3.96v
6: 4.11v
7: 4.12v
8: 8.46v
The bottom IC measures:
1: 4.13v
2: 4.13v
3: 4.12v
4: 0.00v
5: 3.94v
6: 4.13v
7: 4.02v
8: 8.46v
Any tips would be greatly appreciated! Thanks (and thanks for the layout!).
So I still haven't gotten to the bottom of this. I've reflowed a few joints and verified my components and placement, but I'm still just getting a thin, low output overdrive. I cans still take the diodes out of their sockets without the effect changing, so they're still not in the circuit as far as I can tell. I understand now that each diode goes to ground, so they should and do have 0v on one end, but they don't have any voltage up on the first column. Any ideas on what they should be reading and what could be preventing them from getting any voltage? Thanks again.
DeleteI figured out that my diodes read 0v because I wasn't playing through the pedal. If I strum a chord they swing up to about 0.7v. If I substitute 1n4148s for them I hear an audible difference, so I guess they're working more than I realized.
DeleteMy temporary fix for this pedal was to move the Gain 3 wire one row up (so it connects directly to IC1 pin 2) and to move Gain 1 & 2 one row up so it meets Volume 1. Now the pedal really roars and as far as I can tell sounds as it should (sounds pretty much like what the above sample sounds like). The one catch is that now with the gain pot turned 90-100% up, the pedal self-oscillates when I'm not playing. I can control the pitch of the oscillation by adjusting the volume knob on my guitar. I can also get the oscillation to go away by putting it anywhere but first in my pedal chain. It's a rough fix, but it'll do for now. The oscillation is annoying but also really cool, so I'm considering just leaving it be.
and the volume works well to you Frank?
DeleteFrank drop a small resistor less than 100R on pcb to gain 3 and see what happens with oscillaation.
DeleteThanks Boratto. The 100r resitor didn't change the oscillation unfortunately.
DeleteVolume is sufficient as long as I have the mids set pretty high. If I scoop the mids then it's a little quieter than unity gain, so I'm going to try John's mod to try and get some more output from it.
Cool Frank! Please post your experiences on that! It seems to be a great one!
DeleteI did John's volume mod but now it's not passing any signal. I don't think I messed it up, but I've been wrong before - see above haha.
Deleteyep, i did the Johns modtoo, and same result a yours: any sounds too. First i think is my build, but i think it need some tweak to work.
DeleteFrank here an update, in the mod vero, a 1uf cap is missing - as youc an see in the orginal. I got some sound, but it is still weak, and very gateda, bit better with a 1n270 and a bat46 diodes... but it´s just not sound right for my ears.
DeleteThanks for the heads up. Where should the cap be? I can't find a missing cap....
DeleteI built the original circuit and then modified it using John's layout, so I might have different issues than you.
yeah, John updated it yet. was up on the right.
DeleteI wasn't able to get this to work so I undid John's mod. If you still can't get John's mod to work, I would suggest changing your build to match the original and see if it has enough volume for you. As I said, mine has just enough volume as long as I don't completely scoop all the mids. I might build a simple boost circuit onto the output of the board in the future, but for now I'm happy just to have this boxed up and playable. Good luck!
Deleteyou are right. JohnÅ› mod do not worked for me, and the original versios has major issues with the mids and volume. IMHO this project can return into a unverified status. Sadly, I do not recommend this build until the problems are solved.
DeleteI ended up sticking a little Alembic Stratoblaster build on a separate piece of vero and tacking it onto the end of my circuit. Plenty of output and it doesn't take up much space. I also put the gain pot on a footswitch - one side normal operation, one side just shorting the gain wires - so I can switch between completely saturated and more reasonable/stackable overdrive sounds. This pedal sounds outrageously good.
DeleteWhat are some good replacements for the 1n270 diode?
ReplyDelete1N34A can be bought cheaply and in quantity, or pretty much any schottky diode will have a similar forward voltage drop
DeleteI probably find the error on John layout.
ReplyDeleteThe 100K resistor next to the 100uF need to be on line below next to the other 100K. It's the biggest error.
After it's an other error on the left, it's 4K7 and not 47K. You've to find if you prefer 47nF or 10nF, choose your favorite.
My pedal works.
Is this one completely verified or are there still a few bugs? I'd love to add this to my build collection.
ReplyDeleteI've just built it with the john more output mod.
ReplyDeleteit doesn't work properly:
- the volume and gain are very low
Thus I went back to the Rev3 standard output. Now it works fine. I chose the 47nf (and not the 10nf).
I use it on bass, so it's quite hard to tell if it sounds like the original or not, as I haven't found any bass demo of it.
The more output made me wonder. I've studied both layout and noticed that on the v3 layout the 10µ cap has its positive side first connected to pin 2, then to pin 1 via the jumper.
On the more output layout the positive leg of the 10µ cap is directly connected to pin 1 then to pin 2 through 470K resistor and jumper. The problem might be there.
I modified the layout so as to have the positive leg of the 10µ cap being first connected to pin to, then to pin 1.
BTW I have also used the 47K resistor instead of the 470K and vice versa.
here's my modified layout (I had to add a cut between positive leg of 10µ cap and IC pin1) :
https://www.dropbox.com/s/m8xweac1l56wdkz/Quantum%20Mystic_more%20output%20v2.png?dl=0
The V3 works fine; this version works good, thug there's still pretty loud hiss when gain and volume are cranked.
So which would be the recommended layout to use, the one that's posted here, the more output version or the reworked more output version? I'd still love to make this one.
ReplyDeleteGonna go with V3 and box it up with a Ritual. Should be interesting.
DeleteAny chance you could link us to the schematic you used for this?
ReplyDeletethanks!
Finished V3. Very low output and low gain.
ReplyDeleteMaybe I was wrong. I tested it at super low volume late last night so bwing half asleep didn't help much either. It works but the volume control did nothing through most of the sweep. I swapped it to a B25k and its much better. The mid control dictates much of the gain, so I've been leaving it dimed. It works best with my amp set fairly dirty (Orange OR15 modded to #4 specs) which it usually is anyway. It seems to have much less gain than the demo but it's a damn good OD. Thanks.
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteJim, thank you for the feedback... i am waiting your news considerations after the pots changes.
ReplyDeleteI played around with a few different pots for the volume, mids and gain controls. I swapped in a B100k for volume and got a wider sweep than the B25k and it's way more useful than the A100k, so I stuck with that. I tried a B25k and B50k for the mids and it wasn't worth it. I also tried out an A1m for the gain and it was useless..I'm still going to try out a linear pot to see what that does, but I have no expectations. I think the biggest problem is the sweep of the C1m gain pot. It only works with the last 20% or so of the pot, but it works better than the logarithmic pot.
DeleteThis comment has been removed by the author.
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteVince's layout works after adding a link between both pin 8's on the ICs and bringing the bottom leg of the 1uF open the upper left corner. It's a decent overdrive but unfortunately nothing like the original, not nearly enough gain, output and the EQ isn't the same. I'm shelving this one.
ReplyDeleteOK, with the day off from the "blizzard" that hit NJ, I'm positive that I got this pretty 100% working besides that mid scoop/volume drop issue.I looked up mods for the Ross Distortion, since that QM is based on that, swapping the 10k resistor for a 100 ohm on the top left greatly increased output. Using the modified layout it mad everything extremely fuzzy. Swapping the resistor on the V3 board worked perfectly. Also, I just noticed that on both layouts the 11k resistor connected to volume 3 are in different spots. Since I'm using V3, I moved the top leg up one row drastically increasing the low end. The only issue is if you scoop the mids all the way out the volume drops drastically. I'll have to do another demo but I think it sounds very close to the demo and sound awesome pushing a dirty amp. Any idea on how to make the diodes switchable? That may be a nice addition to it.
ReplyDeleteDemo: https://soundcloud.com/squiresj820/quantum-mystic-clone-demo
ReplyDeleteI'm happy with it. Hopefully someone else will get a good build from this too.
Still tweaking it a bit, I noticed that if I had the treble dimed with the gain at above 3:00, it would actually cut treble. I tried something I read in the Crap Fi Delay pad, use a 250k pot with a 220k resistor in series with lug 3 to mimic a 470k pot. Works much better with very little difference in taper. The other thing that bothered me with the mid control, it would cut volume when scooped out. I threw in a C500k pot with a 150k resistor in parallel and the taper is much better, I'm waiting for a credit from Tayda to put an order in and I'll swap in a C100k pot to see if that works better.
ReplyDeleteThank you Jim, i am waiting the new considerations after Tayda.
ReplyDeleteThe C100k makes a world of difference with the sweep and no volume drop unless it's totally scooped out, like the Black Arts demo has. I think the pedal sounds as close to the demo as it's going to get or possibly even identical to it. I'm running it front of a dirty OR15 as a boost and it works great.
DeleteLet me know how it goes when you give it a shot.
Still struggling with this one. Rebuilt it from scratch using values given by Jim (thank you ;-) i.e.
ReplyDelete- resistor top left 100R, instead of 10K
- 11K resistor connected to bass 3, as on original layout, not to treble 3. There was a huge volume difference with it when maxed out, although no more mid scoop.
- pots Gain C1M, Treble C100K, Mids B500K, Bass B100K, Vol B100K
- no more output mod
Anyway as Jim says it's much better, but there's still a big mid scoop and the bass knob doesn't have enough effect to my ears. I'm still wanting to have it sound better.
Something interesting now I think. While searching for a real unit on Ebay, I found a gutshot picture.
I added the resistor values I could read. It is or so it seems to be on a double sided PCB, so it will be hard to trace.
The IC is a TL074CN.
Here's the link to it:
https://www.dropbox.com/s/ljd7itkf5s9wpbl/BAT%20Quantum%20Mystic_gutshot.jpg?dl=0
Let me know what you think.
Hey Vince, try swapping the treble and mid pots. I'm using the C100k for the mids, that eliminates the volume drop with the mid scoop. I'm also using a B250k with 220k resistor in series to lug 3 of my treble pot. With the 500k when it was maxed out it would lose some signal so I tweaked it a bit.
ReplyDeleteSo I'm guessing the layouts have been wrong considering we've been using two IC's instead of the TL074 or can two TL072's essentially do the job of a TL074? Also is there any chance you can let me know which parts I would have to swap out to the corrected values? I'm not very good with tracing a PCB. I'll definitely be a guinea pig for this experiment if I have what's needed.
Thanks Jim, I'll try swapping treble and mids pots, as they should be. My mistake…
ReplyDeleteI'll also try a 120Ω, as I noticed on the PCB that the color code for 10K gives 120Ω if read reverse:
brown-black-black-red-brown = 10k
brown-red-black-black-brown = 120Ω
I'll also think the layout isn't right: some resistors values read on the PCB are different then on the vero layout. I took a closer look at the picture and there is a 5k6 (instead of 11k) connected to bass 3 and an another one connected to bass 2. There must be a 3rd one on the other side of the board going to volume 3. There's also a 6k2 (instead of 1k8) connected to treble 3. The resistors connected to treble 1 and 2 must be on the other side of the PCB.
Also on the far left, located horizontally, above gain pot, there seems to be a diode, or is it an old style carbon comp.
there are also 3 electro caps on the PCB. Thus the layout seem OK for that point.
what is still a bit strange to me is the four big square film caps. they must be the 1µF, but there are only 3 on the hero layout…
I really have to get a real unit to find out its magic.
Hey Vince,
DeleteI swapped out the 11k's and 1.8k's. Much better with the EQ. I also put the 500k treble pot back in and it works fine. Is it possible the extra 1uF cap on the bottom left could be the 1nF that's after the 1M5 on the vero (near the input)? I don't have any extra 1uF at the moment to check myself. I have no clue about the extra diode, there is a third diode on the vero for the black Ross Distortion that the QM is based on:
http://tagboardeffects.blogspot.com/2012/08/ross-distortion.html
If you're going to rebuild it, definitely use the values that you mentioned.
I wanted to edit my last post because I'm unsure if there was an actual increase in low end but there is definitely a change in the treble and bass. Still, it's actually good the way it is.
Hi Jim,
DeleteToday I reworked my 2nd build. Swapped out the 11k's and the 1.8k's as you advised, put sockets and tried different things:
- replaced both 1.8k with 6.2k, works great for mids, no problems with treble.
- replaced the 3 11k with 3.9k+1.8K wired in series, which gives 5.7k, as I didn't have any 5.6k's. To me volume gain was too big with bass at max. I put back the 11K connected to bass 2. Now it's good, I think.
Changed pots: Gain C1M, Mids C100K, Vol B100K
Treble is B500K and Bass B100K as per layout.
Top left resistor is 100Ω, instead of 10K from layout.
The three 1µF are multi-layer ceramic, should be film.
here's my board: it looks a bit messy with all the sockets and series resistors, but it's not definitive yet.
https://www.dropbox.com/s/5m9g1kksmji2y55/Quantum%20Mystic_DIY_VN.JPG?dl=0
Your board still looks better than mine does Vince.
DeleteSo what do you think of it now? Also are you using it as a stand alone source for dirt or as a boost into a dirty amp. I use it as a boost mainly and it sounds great but on it's own I think you are right about the bass being too much with the gain dimed. Since the resistor values changed the EQ quite a bit, would the reverse log pots be necessary anymore?
Mine's all boxed up and was a lot neater at one point. Taking it apart a few times didn't help:
Deletehttp://i275.photobucket.com/albums/jj316/elessar820/IMG_0127_zps049dfa3e.jpg
And the box:
http://i275.photobucket.com/albums/jj316/elessar820/IMG_0128_zpsf558b0b3.jpg
Pretty happy how it sounds now, bass and mids controls are very good now. Treble could be tweaked to be a little more effective, I think. Still have to order some resistors and put back the 1uF film caps. Could also try the change the Bass pot and Volume too, or at least give it a try.
DeleteBox is going to be a 125B with an acid etched design. But I'm not yet done with the graphics, so wait is the word !
Your graphics look cool; hand painted ?
Thanks, yeah I hand paint them all and spray a sealer on them. I live in a condo so my workbench is my kitchen table and my spray booth is outside my kitchen window. Post yours when it's done if you have some time.
DeleteRegarding the pedal itself, I'm very happy with it now. Unless someone comes up with a full 100% accurate layout, I think mine will stay boxed up and on my board. Thanks for sharing what you find in that gut shot, it's much appreciated.
Hey Jim,
DeleteGetting so bored with this one ,I decided to buy an original one and traced it !
Here's my drawing of it and a few pics:
https://www.dropbox.com/s/67q7zhl903u2rcq/BAT%20Quantum%20Mystic_drawing.pdf?dl=0
https://www.dropbox.com/s/5b9vuy0ykbjyl6a/BAT-Quantum%20Mystic_PCB%20pots.jpg?dl=0
https://www.dropbox.com/s/zw50hzkbbtxkqnb/BAT%20Quantum%20Mystic_values.jpg?dl=0
I haven't drawn a proper schematic, but I think I could.
I took mine off my board last week in favor of a Sonic Titan. I had a feeling there were more differences in our clones than the original.
ReplyDeleteI'll bet the actual Quantum Mystic sounds huge compared to the one on vero. I'd definitely give it another shot if a corrected layout was available. How is it?
hola a todos
ReplyDeletequiero saber si esta veroboard ya funciona al 100%.... en caso negativo me darian las pautas para hacer las modificaciones de una vez y sobre la marcha les agradezco ya que me intereso mucho y no quiero tener errores solo lo quiero hacer y ya para ponerlo en mi cadena de efectos..... gracias
hi to all
I want to know if this veroboard and works 100 % .... if not I would give guidelines to make changes once and progress thank you because I care a lot and do not want only errors I want to do and you to put it in my chain of effects.... thanks
Hi,
Deleteto answer your question: this layout works but is not accurate. Some pots values and parts values in the tonestack are wrong.
I built this layout, struggled a lot with it, trying to make it around like the original heard on YouTube. See my previous posts and ended buying an original unit, to know the magic out of it.
I traced it now and finally drew a schematic and here it is.
https://www.dropbox.com/s/wf0e7smzi072xvk/BAT%20Quantum%20Mystic%20-%20schematic.png?dl=0
Maybe it can help you and others ;-)
awesome. that's what ended up happening with the BATW blacksheep. stupid question, did you take out all the components to check for hidden traces? i know in the blacksheep he hid some traces under some fo the components.
Deleteif you did and you're sure of the schematic i'll take a crack at this.
just an FYI..i drew up a PCB & built one from the schematic that Vince posted on FSB but it doesn't work properly at all. IMO, there must be some errors in the schemo.
Deletegod, why is this one actually so hard to figure out?
Deleteit shouldn't be hard at all. there's just some errors in Vince's schematic. if I had the original I'm sure that I could figure it out. it's just a DOD 250 with a 3 band eq tacked on the end of it.
DeleteAgreed, but it's pretty annoying that it's been wrong every time. It should be a Ross grey distortion with Ge diodes and the 3 band active tonestack. I could be wrong but the dod and the Ross distortion are pretty much the same, but I know for sure its the grey because I saw YOB live and he uses a grey distortion still, and we talked about this pedal, and he said it's based on his grey distortion.
DeleteI'm wondering where the active tonestack is from, because if we can find it, we can get this right already.
I got mine working from Vince's schematic but the eq is really not very effective. I wonder if the original is like that? maybe Vince can let us know?
Deleteokay, mine's working properly now.
DeleteI etched a PCB for it. here's a link for the doc for it:
http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/BlackArts/QuantumMystic/002-MysticLayout.png
awesome. what did you do to fix it? does it sound like the original? better then the one based on the layout from mark posted above?
DeleteIn that case I didn't need to take out everything, only the pots and a few resistors. For the rest I traced for continuity between parts with a multimeter. I'm sure of my drawing. You can see it and the pictures I posted in my previous posts, they are all on dropbox.
ReplyDeleteThis on was easier than the Black Sheep where I needed to take out nearly everything (see what I did on Freestompboxes)...
Vincent
OMG, that's too funny. i'm rocket8810 on Freestompboxes. i just fell out of my chair laughing that it's you and i working on another pedal together. i know, my name isn't john, but for some reason it shows up like that here. did you see the layout for the black sheep?
DeleteHi johns/rocket8810,
DeleteWell that's indeed very funny ;-))
Reading your previous comment also made me wonder if it were you or just another who also followed the Black Sheep there. And I laughed when I read your last one.
In fact we worked on the Overdrive Boost too….
I haven't seen your layout yet, pictures of your build only. The etching is great, really pro looking. Great job you did here.
Regarding the Quantum mystic, I wanna try to draw a single sided pcb, but not sure if it's possible. Schematic was drawn using Eagle. I'll chime in when I'm done. I think I'll start a new post on Freestompboxes on this one too.
IMHO this vero layout for the Quantum Mystic is just too different than the original
(different IC, pots and values in the tonestack). It works but should be reworked to be accurate and newly verified.
wait. the overdrive boost? you talking about the one i was working on designing? it's so funny that it's such a small world within this community. the sad thing is that pretty much everyone here knows my name is actually zach, while i still get called john because of how it shows up here.
Deleteregarding this layout that uses 2 TL072 instead of 1 TL074, shouldn't be an issue as i believe the TL074 is just 2 TL072's in 1 package. i think the other parts have to be worked out. i'm first going to see if marks layout can be adapted, and use 2 TL072's instead of the 1 TL074, then work on making one with the single TL074. i think it will be more difficult with the 1 TL074 then the 2 TL072's as they can me positioned to have space for easier parts placement.
side note, you know what's really funny? i saw yob and met mike at a show they played a few months ago at a small bar in NYC, and he doesn't even use this and it's been made with his input and to meet his specs. hit had 3 pedals if i remember correctly, a delay, an old ross distortion (grey i think), and a tuner. also, he's one of the nicest guys i've met in the metal community. not saying all the others are assholes or anything, just he was incredibly nice and humble, and just hung out with everyone before and after the show.
Not sure if anyone cares at all but, just saw them last night and remembered this comment when I was checking out his pedalboard. Seems he's changed it up a lot, he had TWO full pedalboard, one of which literally had 2 of these oh it.. maybe his trusty ross distortion kicked the bucket finally?
DeleteHi Zach,
ReplyDeleteWith overdrive boost I meant the "THROBAK Overdrive Boost".
Regarding the IC you should be right saying that 1 TL074 is 2 TL072, but I'm not 100% sure of this. I'm no engineer, just a hobbyist. Good idea to see with Mark if he can adapt the layout using the drawing I did. I sent him an email on the forum (on Tagboard) but didn't get an answer. I don't know him. I'm quite new on the DIY scene; the Throbak Overdrive Boost was my first attempt on a vero layout actually.
Thank you for the side note. Yeah funny, especially when you know the Quantum Mystic is based on this old grey Ross distortion. My interest in BATW actually began about two years ago when I started a long talk with Mark to make me a modified Pharaoh with different clipping possibilities. The one he built for me then led him to the Pharaoh Supreme. I had it made with etched graphics. It looks like this:
https://www.dropbox.com/s/uck18v6dgltmkud/CIMG2882.jpg?dl=0
https://www.dropbox.com/s/2g6hfyx8lgao9g9/CIMG2886.jpg?dl=0
that's pretty cool, that you know him and the story behind the supreme. i had no idea that you knew him.
Deletei know marks been pretty busy, so he may not have had time to take a look at it. but, i'm sure he will do something if he can. i did post this on the request thread too, so hopefully if someone has more time then me they can take a crack at it.
Someone poster an updated schematic!!! I think it will sound now really great, I never been happy with the last schematic.
ReplyDeletehttp://www.freestompboxes.org/viewtopic.php?f=7&t=26050
con el permiso de todos y desviandome del tema y colocando otro tema diferente... pero en el otro post nadie me contesto...... espero aca si me saquen del problema que tengo....hice el proyecto del ZW44 OVERDRIVE..... y suena.... pero tiene un silbido en el pote de 1M (GAIN) cuando esta a maximo y me toca bajarle casi todo el gain para que deje el silbido y esto me ha pasado en muchos otros, ya he probado de todo he repasado soldaduras... los cable que yo utilizo son apantallados y nada... he cambiado los potenciometros y tampoco, he cambiado el transistor y nada, he cambiado el IC y sigue el silbido, he hecho otros proyectos y les ha pasado lo mismo y nunca he llegado a la conclusion de que podra ser..... en cambio hice el proyecto del MXR GT-OD y me salio de una y sin problemas....... al que me pueda ayudar con lo del silbido quedare eternamente agradecido
ReplyDeletewith permission of each and deviating from the topic and putting a different subject ... but on the other post nobody answered me here ...... I hope if I take out the problem .... I have made the project ZW44 OVERDRIVE ..... and it sounds .... but has a whistle in the 1M pot (GAIN ) when the maximum and touches me to turn down most of the gain to stop whistle and this has happened to me in many others, and I have tried everything I have reviewed the wire welds ... I use are screened and nothing ... I changed the potentiometers and neither , I changed the transistor and nothing, I changed the IC and follow the whistle , I've done other projects and same thing happened to them and have never come to the conclusion that may be ..... however the project did MXR GT -OD and I came over and smoothly ....... when I can help with whistle will stay forever grateful
http://tagboardeffects.blogspot.com/2012/02/mxr-zw44-zakk-wylde.html
post your problem in the forum under the open chat thread.
Deleteno lo hice porque no me contestan... por eso me atrevi a hacerlo aca.... porque este hilo si lo siguen
ReplyDeleteI did not because I do not answer ... so I dared to do here .... because if you follow this thread
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ReplyDeleteMark, if you want, i don't mind to give support in spanish in the blog, but i'm not sure if it's correct or is even a good idea. Anyway, google translator is a piece of crap :P
ReplyDeleteJ.
That would be fantastic if you could mate. I struggle enough supporting the English language at the moment :o)
DeleteMARK... with permission of each and deviating from the topic and putting a different subject ... but on the other post nobody answered me here ...... I hope if I take out the problem .... I have made the project ZW44 OVERDRIVE ..... and it sounds .... but has a whistle in the 1M pot (GAIN ) when the maximum and touches me to turn down most of the gain to stop whistle and this has happened to me in many others, and I have tried everything I have reviewed the wire welds ... I use are screened and nothing ... I changed the potentiometers and neither , I changed the transistor and nothing, I changed the IC and follow the whistle , I've done other projects and same thing happened to them and have never come to the conclusion that may be ..... however the project did MXR GT -OD and I came over and smoothly ....... when I can help with whistle will stay forever grateful
ReplyDeletehttp://tagboardeffects.blogspot.com/2012/02/mxr-zw44-zakk-wylde.html
I used the PCB layout John provided and altered the values of Mark's original layout and came up with this:
ReplyDeletehttp://i275.photobucket.com/albums/jj316/elessar820/BAT%20Quantum%20Mystic%20TL072%20Version_zpsf57rdflb.png
I just made it myself and besides a horrible squealing with the gain dimed (much like Bravewolf's ZW44) it sounds awesome. It's my first attempt at even recreating a layout, so yeah.
If anyone could help with the squealing, that'd be most helpful,
eyy jim thanks for supporting over here what the screech of zw44 if anyone can help please give us your input
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ReplyDeleteHey Vince, I read your post before it was deleted. Should I not do that? The only thing I noticed that volume 2 and 3 would be together.
DeleteHey Jim,
Deletethere are some more problems, thats why I deleted my post. What I said was right but it's not enough.
To make it short, the connections on the IC2 go first to 2nd opamp then to first opamp. That's wrong ! It's not like that on the original.
I'm writing a detailed answer and also trying to adapt there original layout, but it's not that simple.
and here it it… First the layout then the answer.
DeleteLayout adapted. I hope it will work. I haven't tested it yet, but checked connections twice. I hope I didn't miss anything !!
https://www.dropbox.com/s/m7wonsi37ptdbuj/BAT-Quantum-Mystic-v2.-layout.jpg?dl=0
an the answer:
While working on the original (when tracing it) and comparing it to the layout here, I noticed two things (apart from all the values that are now correct):
- the 100R resistor, in series with the 100µF cap to ground, in the power supply is not present in the original. Instead there is a 1N4001 diode in parallel with the 100µF to ground.
- the other thing could be even more important, I think. On the layout the connections to the IC2 go first to the 2nd opamp (2IN, 2OUT), and then to the first opamp (1IN, 1OUT). On the original with the TL074 the opamps are connected 1->2->-3->4.
TL072 pin go like this:
1 1OUT 8 VCC+
2 1IN- 7 2OUT
3 1IN+ 6 2IN-
4 VCC- 5 2IN+
TL074CN pins go like that:
1 1OUT 14 4OUT
2 1IN- 13 4IN-
3 1IN+ 12 4IN+
4 VCC+ 11 VCC-
5 2IN+ 10 3IN+
6 2IN- 9 3IN-
7 2OUT 8 3OUT
I try to explain myself clearly but it's not so easy. Problems begin after the tonestack; the input 1 and 2 of the IC2 are mixed up in the layout:
- Bass1, Mids1, Treble1 go to Vol3 and to IC2 pin7 (2OUT), it should go to Vol3 and IC2 pin1 (1OUT), on the original it goes to IC pin 8 (3OUT)
- Bass2, Mids2 and Treble2 go to IC2 pin6 (2IN-), on the original it goes to IC pin 9 (3IN-), it should then go in the layout to IC2 pin2 (1IN-).
- Vol2 goes to IC2 pin3, it should go to IC2 pin5 (2IN+), IC pin12 (4IN+) on the original.
- IC2 pin3 should go to Vb (row with Vol1).
Vince
hello vince69 and jim that I can do then to remove the squeak ???
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteI have the same problem with the triple wampler wreck and the crunch box and always when the gain is at maximum .. just want to know how to remove the shrieks and you .... thank you very much
ReplyDeleteHey Vince, what does the to and from Vol. 3 connections mean?
ReplyDeleteI meant as following:
Deleteto Vol3 should first go to IC2 pin1, then to Vol3 (violet wire as on my left drawing).
That makes one more double link. I was unclear on this one, my bad...
Did you use my new layout or just altered connections on the old one ?
I used your new layout. I just ran the to vol. 3 wire across to the left side of the board to the IC2 pin 1 track and got nothing. I'll have to play around with it in the morning.
DeleteWhere is the double link Shouldn't bringing the wire over from to vol. 3 to the pin 1 rail do the same thing?
I took a stab at connecting both to volume 3 and nothing. I'm honestly not sure about that connection, I'm probably wrong. If I am, please let me know what I can do to correct it.
ReplyDeleteIt did work before with the altered layout I but I just had the oscillation problem. Maybe a TL074 layout is needed for this one to get it 100%.
Thanks for all the info.
Hi Jim,
DeleteI re-checked my new layout completely, comparing it to the original pcb layout.
Some slight mistakes were found (connections to and from Vol 3) and thus I edited my layout in v2.2
Now it should be 100% OK.
link to my layout on dropbox:
https://www.dropbox.com/s/vfctyp1dqko49o0/BAT%20Quantum%20Mystic%20-%20layout%20v2.2.pdf?dl=0
V1nce69
Still nothing. I got crazy voltages too.
ReplyDeleteTop IC:
1: 1.38v
2: .96v
3: .91v
4: 0
5: 0
6: 4.11v
7: 8.13v
8: 8.79v
Lower IC
1: 8.03v
2: .13v
3: 0
4: 0
5: 8.02v
6: 8.03v
7: 8.03v
8: 8.72v
I'm going to order more parts to take another shot at this. Would it be more realistic if a TL074 was used considering that's what is already in there?
ReplyDeleteVince, if there is another fix for your TL072 layout I'd definitely be willing to try it out.
Another question is that if the original layout is so far off from the actual schematic (not including the difference in ICs) why did it work when I rebuilt it with the altered values... besides the oscillation?
a TL074 is exactly two TL072's in one chip so that wouldn't make any difference at all.
DeleteI get that, but what I meant was would it be easier to make a new layout with the TL074 as opposed to two TL072's? That way the pins wouldn't need to be transposed to accommodate the two separate chips.
ReplyDeleteOk, after a little debugging, Vince's V2.2 layout works... Almost. The mid pot turns to a mid cut when maxed out. I'm guessing that I can put a small resistor in series with lug 3 to lower the value a bit but is there a flaw on the layout I'm missing?
ReplyDeleteI had the double link that goes from pin 1 on IC2 to volume 3 going to mids 2. After correcting that, the EQ began to work correctly but now oscillation when everything is maxed out. I must have a damaged component since last time I had this problem was with the BAT Black Forest which I rebuilt and it's fine now. I'm about to give up on this one for good but I think I'll give it one more shot rebuild the board.
ReplyDeleteHi Jim,
ReplyDeleteI rebuilt it from the ground up using my new layout v.2.2.1 and I can confirm it works, though I have a squeal when both gain and any tone pot are maxed out. I don't know why. It disappears with either pot just a little CCW. This squeal isn't present on the original.
Regarding the mid cut, it does the same on the original. with Mids fully CCW there is a strong mid scoop; it's about flat between 12 and 14, there's a mid bump fully CW.
Bass pot on the original behaves the same: fully CCW bass scoop, from 15 to full CW bass bump.
On the layout v.2.2, value of the Vol pot was wrong, i.e. 500K log, instead of 100K log. It's now corrected in v.2.2.1. I tagged it as VERIFIED.
Here is the link for it:
https://www.dropbox.com/s/b15sqt0af6my4xh/BAT-Quantum-Mystic---layout-2.2.1.jpg?dl=0
Notes on my build:
- Treble pot is a B500K, as I didn't have a 500K log.
- Gain pot is a C1M pot with a 1M resistor wired in parallel with lugs 1&3.
- 5k6 resistors are a 4k7 and 1k in series, which makes a 5k7. Those a used in the bass eq.
- the small yellow cap on the top is a 1µ multi layer ceram cap, the film one wouldn't fit there.
Here are the the voltages I have on the IC's. Power source is a T-Rex FuelTank Jr
IC1
1 4.54v
2 4.20v
3 1.81v
4 0v
5 3.02v
6 4.20v
7 4.52v
8 8.99v
IC2
1 4.53v
2 5.99v
3 3.02v
4 0v
5 3.0v
6 4.55v
7 4.54v
8 8.99v
And I took some pictures of the board itself:
board components side
https://www.dropbox.com/s/38ti5qjaqzwlrv1/IMG_0708.jpg?dl=0
general view
https://www.dropbox.com/s/860lfsma3nm8a4f/IMG_0709.jpg?dl=0
solder side
https://www.dropbox.com/s/9dm175exn9vjg9h/IMG_0711.jpg?dl=0
So your last version it's the "good one"? Thanks a lot for your work!
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DeleteIt works and sounds great. I had to stick a small buffer in front to tame some oscillation though. I had two different build and both did the same thing.
DeleteThanks, and compared to the original one?
DeleteI'd call it verified too but I recommend a buffer in front. Sometimes I'll get some oscillation when everything is pretty much at max but I don't use it that way.
ReplyDeleteVince, thanks so much for everything. It was incredibly generous to share what you found in your pedal. It is very much appreciated.
Here's a quick soundclip: https://soundcloud.com/squiresj820/quantum-mystic-clone-demo
ReplyDeletePRS SCT (Lace Hammerclaws)-->QM Clone--> Orange OR15 (modded to #4 spec)--> PPC112 cab--> iPhone Garageband... yeah, I don't have a good mic or anything.
The QM was set as:
Volume:10
Bass: 10
Mids:8
Treble: 4
Drive: 7
It definitely sounds better with the drive up.
I finished mine with the Vince69 layout sounds great, but I also get the oscillation when I put the gain full and turn the mids. By the way, it's really cool :)
ReplyDeleteI used one of the JFET buffers in front of mine and it cured the squeals. I'm using it as a dirty boost and it sounds awesome. Between this, the Black Forest and LSTR I have my doom, stoner and sludge tones covered.
ReplyDeleteThe oscillation is in all three confirmed builds. I also had it when I changed the component values on the original layout. Could the use of two separate IC's have anything to do with it.
Maybe it depend if we use TL072 CP or IP?
Deleteor find TL072CN (I never get one) like the TL074CN on the original pedal.
DeleteBuilt using the v.2.2.1 layout.
ReplyDeleteLike others have reported , it squeals when the controls are up. I experimented with other op amps:LM833, NE5532, OPA2134, but it was the same.
There's no squeal at all when I use active pickups, or place it after a buffered pedal, so I'm going to add a simple buffer to the input as others have suggested.
The buffer worked pretty well but could it be something with the layout itself? I know that two TL072s are essentially a single TL074 and the original posted layout had no issues but could there be some type of interference with the difference EQ and higher gain? It's a massive sounding pedal using Vince's layout.
ReplyDeleteJohnK did a PCB layout with a TL074, I wonder if his had the same issue?
mine has zero issues with no mods
ReplyDeleteSuccess. I just built it on perf board with a TL074 using your layout as a guide. I only had to nudge a few parts over.
DeleteIt's dead quiet, high gain and the tone section works just like my v2.2.1 TL072 build. The bass and mids cut a lot when fully CCW.
Correction, after comparing my vero board adaptation of JohnK's layout with the updated schematic linked at "13 April 2015 at 23:41" , I linked Vol#3 with pin#8 of the TL074.
DeleteIn other words, the 5.6k from bass#1 is now connected to the 3.6k off mid#3 and the 6.2k from treble #3. The treble control now works as well as the other controls.
This is only for that TL074 build, the layout posted here has the correct connection, and I also built it (w/ original EQ values) and got it working, but it squealed without a buffer at high settings.
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ReplyDeleteHi, First of all, congratulations for this website.
ReplyDeleteI built it and it sounds great! but I have a problem of a big pop when i switch it on and off. Do you have it too?what can I do?
Decrease the 1M resistor from out to ground to 1k.
DeleteThat will make the effect dramatically less loud
DeleteYes, but it is loud enough. I used all the methods to prevent pop, but no one worked here.
DeleteSO this seems to be dead now sort of, but I was curious what version people are building now. The one at the top or the 2.2.1 in Vince's post? It seems the Vince layout with a buffer in front of it is the choice? What buffer would you recommend if anyone who has built it with a buffer cares to chime in :)
ReplyDelete-Brett
https://www.dropbox.com/s/vfctyp1dqko49o0/BAT%20Quantum%20Mystic%20-%20layout%20v2.2.pdf?dl=0 i built it with a buffer. Work really nice, but i switched the 1m resistor from out to ground to 1k.
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DeleteCan we get an updated version of this with the TL074?
ReplyDeleteIs this veryfied without changing the component?.
ReplyDeleteIs this veryfied without changing the component?.
ReplyDeleteIs this veryfied without changing the component?.
ReplyDeleteHas this been verified/ is the current layout updated?
ReplyDelete