led hard clipping, adjusting the decay

[pinkjimiphoton]

hey fam
so i got this new thing i'm working on, began as a bluesbreaker but its been fairly molested genetically

i kinda been digging pink leds for clippers for a while, they break up really nice... but on the decay, when they run out of voltage, it bugs out.

low notes and chords will cut off rather abruptly, high notes will change pitch before dropping out completely.... usually down a 4th! kinda cool...almost.

i have a switch, on off on... one side is ge and leds, center no clipper, other side just the leds.

the ge diodes n<1n34a> allow a BEAUTIFUL BREAKUP with the led's..with a natural fade out that doesn't glitch.

so i don't want to add them to the other side. so i was curious is maybe a schotke or even a 914 would allow a similar fade?

maybe adding ONE ge diode?

its already boxed so i hate to rip it apart needlessly

i know, sockets are your friend, pangkay.... 


of course, the schematic





in the box








basically a modified guitarpcb.com bluesbuster

i changed the 1.5n from u1 to ground to 470p 1.5 was overkill

anyways... i'm open to anything with this.. maybe a big cap between that clipper n ground?


thanks peeps

[Fancy Lime]

Hi Jimi,

sorry, I don't quite get what you want to do, can you elaborate? Do you mean: "what if the I use the same diode setup as for the feedback clipping also for the clipping to ground?"

Something I like for smoothing the decay of the clipping goes a something like this:
LEDs directly to ground as usual.
Parallel to that, a pair of lower threshold diodes (Si, Ge or Shottky, adjust to taste) in series with a 1k-10k resistor or a 10n-100n cap (again, adjust to taste). With the resistor it mostly softens the clipping knee, which has little effect while the signal is loud but takes care of the abrupt fizzing out on decaying notes. With the cap it mostly clips transients (depending on the cap value) but may also make the sound boomier on the louder notes (try making the DC blocking cap in the clippers of a Big Muff 22n and you'll know what I mean. Also do that for the ultimate stoner rock Muff but I get sidetracked).

Does that help at all?

Andy

[pinkjimiphoton]

andy, that's perfect.
i looked at jack orman's warp controls too, had some plays with various circuits, but it seems a 1.8k resistor (jack reccomends 2k) in series from vb to the led's is all it took.. still get the tone and compression of the leds b<yes pink ones DO sound different> but the fade out is nice n smooth with a good sustain and feedback.

so... problem solved, thanks man!!!

[Mark Hammer]

Sir James, take a hint from the Big Muff Pi.  It clips, then boosts again, before re-clipping, which is the secret to the long sustain.  You have a complement of diodes in the feedback loop that provide one degree of clipping, and the output of that op-amp feeds some diodes with a lower clipping threshold.  When the signal+gain is insufficient to clip in U1b, the likelihood of clipping via the LED pair to Vb goes down considerably...unless you insert some gain between U1b and the LED pair.

OR, as you suggest, replace the LED pair with diodes having a lower forward voltage.

Personally, I find "Presence" controls on these Bluesbreaker-derived circuits a waste of time and parts.  Run a cap to ground from the junction of R12 and the diodes to take out the highs you don't, and will never, need and be done with it.

[pinkjimiphoton]

hi Sir Mark
i got my own big muff too, lol, wanna see it?



the loudest big muff of all. for all intents took a violet rams head and grafted in a 3 band active bax where the tone stack was. wanna talks sustain? fugeddabout it!

impossible to crank all the knobs open... heheh #FuzzyGoodness

what i ended up settling for was turning it into more of a "warp" control. i think due to the size of the huge caps added to the breaker circuit, it was motorboating/oscillating somewhat with the gain pegged .

i did a little lookin around and revisited jack's warp controls and realized it needed a series resistance to actually function well... so about 2.7k seemed to work. kept most of the tone <yes, them pink led's sound wayyyyy different than the common green and red... btw, pink and green are light spectrum opposites> and allowed a much better decay from the leds. it still glitches a little, but the sustain's about thrice as long now and it fades out close to perfect.... well, as close to perfect as led's allow.

i LIKE the presence circuit, but i did revoice the circuit a bit. i made it a trimmer,  cuz i darkened up the signal some earlier in the circuit and it adds a nice edge.

barry calls it a treble control, but its more presence than treble.  the tone control works better when its there as well i found.

does it merit a knob on the face? hell no.

i will try and get video at some point this week. i've been busy poppin fuzzes out
and getting ready for the "premiere" of 3 circuits from a georgia company called missing link audio i've been working with. should be fun. i redesigned their pea%^&* and devised a couple other things for them.
i can't share those circuits


yet


lol

[willienillie]

^ D5, D6, D9 aren't doing anything.

[Gus]

You can simplify the 6 diodes to 5 with the 4 others being a bridge with the pink in the middle

[pinkjimiphoton]

^ D5, D6, D9 aren't doing anything.

yeah they are. breadboard it and take them out. see what happens.

any EE shit goes out the window with fuzzes dude.
the 1n34 and led in series is a great clipper sound, you should try it.
the 914 raises the clipping threshold a little higher. for all intents, the 1n914 and led in series gives you a little over 2 volts of compression, and the germanium slows the discharge of this voltage considerably.

as for d9, it absolutely is making a difference tonally as well, in fact, that was where the issue i asked about was happening from. adding a small resistance between vb and the top side of the clipper helped smooth out the decay.

smaller signal diodes won't work there. oscillation. ya need something robust enough to take more than a volt there, standard silicon or ge you can only clip one side of the wave without the circuit becoming unstable. two leds however can handle the voltage just fine and have a marked effect on the tonality of the pedal.

peace.

[pinkjimiphoton]

thanks gus
i'll try that sometime.
but for this, its done. the ONLY time i normally use leds for clipping is with the ge in series. otherwise i don't much care for the tone. so i'd be more inclined to ditch the 914's, but they are part of what keeps the volume of that particular clipping stage up... the ge drops it down a lot, even with the leds and the si's help "bring it back up" as it were.

the stock as per barry's build doc would be two 914's in series with one led on one side, and one 914 and one led on the other, and the warp control 2 3mm red leds. fwiw. i see why he did it like that, it was so the volume would stay about the same between the two ways of clipping it. i added a center off position so i can have either or none, which i prefer.
nice hearing from ya man.
peace!

[dschwartz]

^ D5, D6, D9 aren't doing anything.

yeah they are. breadboard it and take them out. see what happens.

any EE shit goes out the window with fuzzes dude.
the 1n34 and led in series is a great clipper sound, you should try it.
the 914 raises the clipping threshold a little higher. for all intents, the 1n914 and led in series gives you a little over 2 volts of compression, and the germanium slows the discharge of this voltage considerably.

as for d9, it absolutely is making a difference tonally as well, in fact, that was where the issue i asked about was happening from. adding a small resistance between vb and the top side of the clipper helped smooth out the decay.

smaller signal diodes won't work there. oscillation. ya need something robust enough to take more than a volt there, standard silicon or ge you can only clip one side of the wave without the circuit becoming unstable. two leds however can handle the voltage just fine and have a marked effect on the tonality of the pedal.

peace.

Then your breadboard is not like the schematic. Those diodes are not doing anything unless connected to the transistor collector. EE works in fuzzes, "dude", a short is a short, and no connection is no connection everywhere.

[pinkjimiphoton]

dude, which thing are you referring to? there's no transistors in the circuit in question, its a 1458 ic. you're confusing one schematic for another.

you can connect a clipper to vb or ground

this is a modification of a commercially available pcb
seeing as how there's been many of them built and other than my changes to it drew it verbatim to the original schematic.

https://guitarpcb.com/wp-content/uploads/2018/06/BD_Blues-Buster.pdf


i think the confusion is coming fron two things

first, you guys are referring to a modded big muff schematic, not the modified bluesbreaker

second i think you're seeing the box i drew around part of the switching as connections. the connection should be dashed i guess but drawing shit up at 3 am i guess i just drew a box around it, its for me anyways for my book of shit i've cobbled together.

if i look at it from what i thiMk you guys see, it looks like there are 6 diodes connected cuzza the box drawn around where it says sw1a dpdt center off.

there are two 914's on one side of the switch. the other side is leds with ge's in series with them forming the diode clipper for the other side of the switch.

in the center it lifts the connection for no diode clipping, the so-called muffbender mod.

so you guys are looking at the schematic i posted to mark as a bigmuff with a 3 band eq grafted in.

not the one in the thread. i guess ya didn't read big muff variant?

you guys are getting butthurt "dude" talking about a completely unrelated circuit.
my bad for the way i drew it. so i'll split the difference with you.   

look at the schematic in the original post.

i'm not gonna argue something that's built when you aren't even looking at the circuit the thread was about.

maybe if you read the posts you would have noticed they were two vastly different circuits.

there's no warp control in the big muff, and no "collectors" in the bluesbreaker.

"dudes"



ahem.... anyways, as reported, issue solved, a small resistance will help the fade out... not perfect, but unless trying to play really long notes without FAS
i can live with it.

late

ps no breadboard involved or needed here, i suggested trying it to see cuz i hear a lot that this don't work and that don't work, and a lot of ya'll would be surprised what you can get out of stuff using it completely wrong. EE is about minimizing distortion more than intentionally creating it in most cases. i speak only with what i do, i guess ya never seen me mention i am just a monkey with a breadboard?

peace

[DIY Bass]

EE is about minimizing distortion more than intentionally creating it in most cases.

peace

oh man, this reminds me of a time in about the mid 90's I think when Electronics Australia published a project for a valve guitar preamp.  It had a power supply of a type I had never seen before (from memory a type of switch mode thing like you see these days) to give high voltage for the tubes.  The engineer who had designed it basically said "I have no idea why guitarists seem to like valve preamps but they do so here's one that I designed, and these are all the things I did to get the distortion level as close to solid state specs as I could"  So, so missed the point.

[Fancy Lime]

Hi Jimi,

I think I know where the confusion is coming from. You are talking about D5,6,9 in your blues thing schematic, the others are talking about D5,6,9 in your Muff thing schematic. In the latter they indeed do nothing at all because they are shorted or dangling (depending on which way you want to look at ist). If the Muff thing is breadboarded they might still have an audible effect, if the parasitic resistance of the shorting connections is high enough, which should not happen but does. But that is of course neither shown in the schematic nor reproducible.

Andy

[willienillie]

I think I know where the confusion is coming from. You are talking about D5,6,9 in your blues thing schematic, the others are talking about D5,6,9 in your Muff thing schematic.

Yes, sorry, I edited in the "^" but I should have been more clear.

[pinkjimiphoton]

Hi Jimi,

I think I know where the confusion is coming from. You are talking about D5,6,9 in your blues thing schematic, the others are talking about D5,6,9 in your Muff thing schematic.

yep. i figured that out trying to understand what in @#$% they were babbling and getting hostile about. the question i asked was dealing with an issue in the blues thing that has been figured out. they're basing stuff on a completely different circuit cuz they didn't bother to read the thread.

In the latter they indeed do nothing at all because they are shorted or dangling (depending on which way you want to look at ist).

i guess you don't read either. what you're calling a short, as explained is a box i drew around the switch to remind myself its part of the switching.  side one is 2 914s anti parallel. side two is 2 leds in series with 2 ge's in antiparallel. the switch  chooses either side or none.

this is most assuredly NOT rocket science here man. not coming from me. nothing i do is particularly hard.

If the Muff thing is breadboarded they might still have an audible effect, if the parasitic resistance of the shorting connections is high enough, which should not happen but does. But that is of course neither shown in the schematic nor reproducible.

Andy

andy,

how many big muffs are there in the world? millions? billions? they all use the same topography in the clipping. booster stage, clipping stage, clipping stage, tone stack, recovery stage.

you're telling me a big muff doesn't work?

oy. i guess i'll learn my lesson again from years ago and stop posting anything to the community. sick of getting shit from folks that don't even know what they're talking about, not thru ingnorance, but from being too lazy to read shit.

whatever.

if you breadboard it, you'll find it works fine, like the million others who have done the same or similar.

again, you guys are ranking on a circuit that isn't even the one in question, and breaking my balls over something that does indeed work, and fine, with nothing short circuited.

whatever.

you are all wrong. where i was wrong was, again, drawing a little box around the switching and not dashing the lines on it so you can tell its  a box, not part of the circuit.


here's the exact same @#$%ing thing with the little box edited away. no other changes to the circuit. still gonna tell me its shorted and can't work?

again... breadboard it. then call me.




here's the part in question isolated. it absolutely does work, no shorts, no bullshit.

bonehead @#$%in simple, too.





stick a fork in me. life is too @#$%ing short to deal with butthurt. from  now on, i won't share any more stuff with the community. its just not worth it.

outta here.

[aelling]

Jimi, I guess what they are failing to explain is you have C9 between Collector & Base of Q3, instead of between Collector and the clipping diodes.

[willienillie]

It's these three diodes that are doing nothing:

[Fancy Lime]

Hi Jimi,

geez, sorry, no offense meant. I especially did not mean to ignite an international incident around "D5-6-9-gate". But since I am not known to be one to ever let anything go unless I have been convinced to have been wrong or don't care about the other persons opinion, here goes:

oy. i guess i'll learn my lesson again from years ago and stop posting anything to the community. sick of getting shit from folks that don't even know what they're talking about, not thru ingnorance, but from being too lazy to read shit.

Please don't. I enjoy the work you are putting out there and was delighted to see you increase your output recently. I am genuinely trying to help. Either help you or, if you don't want or don't need the help, others who read your schematics and may be confused at points that flummox me as well. Same goes, I suspect, for the others pointing out the same things here.

yep. i figured that out trying to understand what in @#$% they were babbling and getting hostile about. the question i asked was dealing with an issue in the blues thing that has been figured out. they're basing stuff on a completely different circuit cuz they didn't bother to read the thread.

Yepp, that sort of thing happens. But I doubt that anyone was trying to get hostile about it. All praise the interwebs.

i guess you don't read either. what you're calling a short, as explained is a box i drew around the switch to remind myself its part of the switching.  side one is 2 914s anti parallel. side two is 2 leds in series with 2 ge's in antiparallel. the switch  chooses either side or none.

this is most assuredly NOT rocket science here man. not coming from me. nothing i do is particularly hard.

Ok, so here you lost me. I was talking about this schematic:
https://postimg.cc/SXKfxqsQ
Specifically about the diodes D5, D6, and D9, which sit (almost) in the feedback path of Q3. Yet what you have just described sounds to me like it refers to the clipping arrangement of Q2, namely diodes D1, D2, D3, D4 for position C of Sw1A and D7 and D8 for position A. Sw1 is the only switch I see near diodes with a box around it (I assume Sw1B is just used to switch indicator LEDs and is not in the audio path, correct?). But, to reiterate: This is not what I am (or any of the others are) talking about. The clipping arrangement of Q2 with D1-4 and D7,8 is perfectly fine and indeed a fairly common Muff mod. My issue is exclusively with diodes D5, D6, and D9, which should be in series with C9 but aren't. Again, no disrespect meant, just trying to clear up some misunderstandings at this point.

here's the part in question isolated. it absolutely does work, no shorts, no bullshit.

bonehead @#$%in simple, too.

Again, that is not the part in question. Just saw that willienillie beat me to it with his much more concise response. BTW, that D5, D6, and D9 don't do anything does not mean that the circuit will not work. It will work just fine, only these three diodes will not contribute. Instead Q3 will amplify unimpeded ad likely clip on its own, which will result in a very loud fuzz tone and probably sound quite nice. I have skipped the clipping diodes on Q3 in the past and was quite pleased with the result.

stick a fork in me. life is too @#$%ing short to deal with butthurt. from  now on, i won't share any more stuff with the community. its just not worth it.

outta here.

And here again I want to invite you to reconsider. And I'd like to state for the protocol that I, and I am sure the others, are not butthurt by your rejecting our criticism. It's not even criticism, rather pointing out that, in all likelihood, there is a single line and connection drawn in the wrong place in a schematic. It happens. A lot. I have few schematics where I did not have to edit errors like this (and much more serious ones, but that may just be me), unless someone else corrected them for me before I had the chance. PRR did that to one of mine recently and I'd like to thank him for it. We all make this kind of mistake all the time. Pointing out you made one too is not supposed to be a personal attack or ridicule of your work but a lill help from friends. Although I see how single sentence forum communication between people who never met in person, don't see each others facial expressions or hear their tone of voice and may come from different cultural and language backgrounds may lead to misunderstandings about the intentions of such pointing out.

In summary, please don't go and don't stop sharing, I like your stuff and I'm sure so do others. And if you think I am trying to offend or ridicule you or anyone, please know that I try to never do either of those things on this or any other forum or in any format other than face to face, where the offendee would at least have the opportunity to punch me in the face, should they deem it necessary.

Andy

[pinkjimiphoton]

It's these three diodes that are doing nothing:

ahhhh, NOW it makes sense. ok, yeah, absolutely right, the connection from c9 is on the wrong side of the clipper. it needs to be moved over to where d5, 6 and 9 meet.

i agree. mistake on my part, and a good catch. will fix it, and thanks to all for catching it.

like i said, 3 am spurious scrawling.

i thought, until i figured out where the confusion came from, they were talking about the circuit i was asking about in the first post, not the qnd muff variant i posted in the reply to mark.

so my bad, and yep, i'm an asshole. so my apologies.

[pinkjimiphoton]

@#$%, dude, i'd rather hoist a point or blaze one with any of ya'll than ever get angry or wanna punch anyone.

yeah, the miscomunication came from not talking about the same things i didn't even look at the 3rd stage clipper cuz when they said d4 5 6 wouldn't work, i was like... wtf?

i figured they must have thought the box was meant as connections, and for that too, i apologize.

i'm actually releasing a bunch of stuff into the wild via deadend fx, so there's gonna be pcb's for a bunch of my stuff available for peeps if they want 'em. or they can etch their own, or vero , or whatever.

so i am grateful for the mistake pointed out. i really at first had no idea wtf peeps were talking about at all.

so again, my bad. interwebs. 

this should be right. not related to the op, but... this should be good. thanks gents.