been a while, thought i'd post something new...

[pinkjimiphoton]

all good bro, hell, a couple days ago i was arguing that my flux capacitor was warping time and space.   

man... laudanum. gotta love it.

[pinkjimiphoton]

here's a preliminary vero. unverified. maybe  build it tonite....

seems good to me, but i'm the king of f'n up

[Jdansti]

Cool Jimi.

I etched a board today and got everything soldered to it. Still need to connect the offboard stuff and then test it. Anyone else working on a PCB version?

[pinkjimiphoton]

got the first vero populated. revised it a little obviously so i gotta re-do the vero... we'll see if it flies

[Jdansti]

I tested mine tonight, but I have a mystery.  When the comp switch is OPEN, the signal is louder and it makes no difference whether the clipping diodes are in place or not.  Maybe this is normal. 

However, when the comp switch is CLOSED, only the diode that has the cathode (bar) connected to 1M resistor provides clipping. Turn that diode around and there's no clipping.  In other words, when the diode's anode is connected to the 1M resistor, it does nothing.  I've tried multiple diodes of different types and it makes no difference.  See below.

Any ideas?

[GGBB]

I tested mine tonight, but I have a mystery.  When the comp switch is OPEN, the signal is louder and it makes no difference whether the clipping diodes are in place or not.  Maybe this is normal.  

I think that's normal. The 1M to ground is enough resistance to prevent much signal relative to output from passing.

However, when the comp switch is CLOSED, only the diode that has the cathode (bar) connected to 1M resistor provides clipping. Turn that diode around and there's no clipping.  In other words, when the diode's anode is connected to the 1M resistor, it does nothing.  I've tried multiple diodes of different types and it makes no difference.  See below.

I wonder if there is DC offset present there. It looks like there could be/probably is based on the schematic. Try a big cap between the wiper of the baalz control and the diodes.

EDIT: Maybe a better place for the cap would be between the diodes and the switch or between the switch and ground. Putting it on the baalz wiper might affect the filter effect of the 470n->baalz->100R->ground which may be nothing but I'm not sure.

[Jdansti]

I tested mine tonight, but I have a mystery.  When the comp switch is OPEN, the signal is louder and it makes no difference whether the clipping diodes are in place or not.  Maybe this is normal.  

I think that's normal. The 1M to ground is enough resistance to prevent much signal relative to output from passing.

However, when the comp switch is CLOSED, only the diode that has the cathode (bar) connected to 1M resistor provides clipping. Turn that diode around and there's no clipping.  In other words, when the diode's anode is connected to the 1M resistor, it does nothing.  I've tried multiple diodes of different types and it makes no difference.  See below.

I wonder if there is DC offset present there. It looks like there could be/probably is based on the schematic. Try a big cap between the wiper of the baalz control and the diodes.

EDIT: Maybe a better place for the cap would be between the diodes and the switch or between the switch and ground. Putting it on the baalz wiper might affect the filter effect of the 470n->baalz->100R->ground which may be nothing but I'm not sure.

Thanks for the suggestions. Gord. I tried them and other ideas I had and couldn't get a diode to clip when its anode was connected to ground. Even with the one diode providing asymmetric clipping, it sounds great, so I went ahead and boxed it as-is.

It would be nice if someone could check this on their build.

[pinkjimiphoton]

hi guys,
i did build this on vero finally.... some good news, some bad... the original works... as it was drawn... but i think parasitic capacitances may cause me some issues.

first off, seems transistors barely matter.... ge sounds better, but si works too in either position. i tried 20 some different ge's last nite, every single one worked. so did most of the silicon ones i tried, tho some it sounded more like a treble booster than a fuzz.

i left off the "mojo" cap... and discovered without it, the diodes don't do squat without it for some reason. not that it matters..

the 1m to ground below the diode clipper seems to work  out fine, but switching the diodes to ground by bypassing it seems to kill 90+ % of the output. so i'm leaving it as is and not switchable... as mictester said, too much gain loss to be useful and they really don't contribute much to the tone apparently... on the original, they provided a hint of compression, but i don't think they matter really.

grounding the bottom of the snarl pot thru a 1m resistor seems to work better than directly grounding it. fwiw, it sounds better left floating.

i found with some transistors, reversing the leads to the saturation pot seemed to help... ie reversing input and wiper, so the wiper connects to the 33k resistor. if having issues, it may be worth playing with.

but, all that said, the clippers don't make much difference, and this thing will RIP. i can still get all the string/synth/woodwind sounds out of this one, so i guess it's a win-win.

i'll up a proper vero in a bit when i get a chance, i matched the one i built while troubleshooting the other nite and have a working verified layout.

for some reason, it seems like i was unsubscribed from this topic, weird!!

jdantsi, i hope ya diggit bro

gord... thanks for all, you have the patience of a saint.

[stallik]

Working on mine with my grandson. He's nearly six. Etched and drilled the board today. He had some difficulty with the etching as his gloves were too big as were the safety goggles but the board looks fine. Popped some of the used ferric chloride into a jam jar with a shiny nail hanging from the lid so he can watch it rust. Had to hold him back when it came time to drilling. He likes that bit so much that, left to his own devices, he'd pepper the board with enough holes to make it look like vero!

He's had enough electronics for today and wants to build train sets now. Suppose I'd better help him with that too

[pinkjimiphoton]

awesome

i built my first "commercial" one, someone bought it cash up front before it was even built. the new one is slightly simpler, but works better.

i would leave off the switch for synth/fuzz. it's not necessary really. i wouldn't ground the snarl pot. it simply sounds and works better ungrounded.

as for the "comp" switch, don't bother with that either.. the 1m resistor to ground kinda makes it superfluous. switching it makes no perceptible difference in that case.

that said,  the correct wiring for the saturation, as on the original, is more distortion COUNTERclockwise... should be cleaner fully clockwise. the reason? you are cutting the saturation as ya turn it to the right, and at full saturation (turned left) it will be quieter. may seem counterintuitive, but i left it like that from the original one. we're so used to turning stuff "up" to get distortion, but in this case, we need to turn it DOWN.... dig? turning to the right the volume goes up, but the saturation goes down. remember... all the knobs interact some.

if wired like i'd originally posted, the saturation and snarl should be at 9 and 3 o'clock respectively, and the baalz and volume should be the opposite (3 on the baalz, 9 on the volume) to find the "string/woodwind" sounds... or around there. the best sounds are not necessarily "on 10". neck pickups work better for the special fx, the bridge is better for traditional tones.

a good place to start is to put all the knobs half way up and go from there. it's wicked dynamic, volume pot sensitive and can go from a mild overdrive with the guitar rolled back to full out fuzzy goodness and all points in between. hope ya diggit as much as i am.

[stallik]

Thanks for the heads up on the switches. Got a bit ahead of myself preparing for the build with my new assistant and already have a box for it. Have to find something else to do with them. Waiting for delivery of the germs and a couple of pots. They should be here by the time of his next visit

[stallik]

Ordered some AC176's for this project and all 10 have hfe's of 5 - 9! Teach me to order from fleabay. Tried with a number of other npn's but the sound is sadly lacking. Will have to reorder. All the trannys I've tried work in that they pass sound but that sound is not good. May have a separate issue but will wait for the correct ones before pulling the circuit about.