Small Good Distortion in 1590A box

[somnif]

Just a details, I bought the 9mm pots from two differents shop to find the right value. Both had a little bump, I don't know how I can call it, but you know, even the 16mm potentiometer had it, we break it to fit it into the box. Just the one on these 9mm is enough tall to make the pots crooked but too much short to break it. This time I menage try to dig a cavity (not a hole) on the inner side of the box and trying to gride with a 240 grit sandpaper. I just struggle a bit.
Is there some better way to do that?

Thanks!

I use a file to rasp the tooth off 9mm pots. Its easy enough to snap them off the 16mm varieties, but haven't thought up an easier way for the little guys yet.

[vasilis]

Did you have any success with the Acapulco Gold? Im still not 100% pleased with it and the reason is that although the original cleans when the volume on the guitar rolls off, mine doesn't. I've searched everywhere about that issue and can't find nothing related.
Any advise will be welcomed!

[JackSkellington]

No, actually I am not going to build Acapulco Gold. Not briefly, anyway.
LM386 circuits should clean up nicely, I think. It was ok with my Noisy Cricket (the gain pot works about like that). My guitars clean up well the Smokey Amp.
The Acapulco Gold could be a bit different. I don't know.
What is your guitar? If you set the volume guitar pot at 3/10 or lower can't it clean up the overdriven?

[JackSkellington]

Some little news. I'm still not building anything, I have to order some materials. Probably I'll try the Smash Drive based on the LM386 anyway, but I found something different that I could like more.
The Mockman 2.0 by ROG, http://www.runoffgroove.com/mockman.html. I can build the perfboard layout on the ROG web site, or use this one: http://effectslayouts.blogspot.com/2018/05/run-off-groove-mockman-20.html
If I am good enough I guess I can fit it in a 1590A box.



It's a one-knob efffect, Volume pot only, but I'd like to have a gain control. I'm more comfortable with non-inverting input stage so I have to try, because I not sure how they could work, some solutions to get a good gain control.

1. Pre-Gain: a pot at the begin of the circuit, like the guitar's volume pot.
2a. In the first opamp feedback, with a basic resistor (33k?) and a 1M pot (linear or log?).
2b. The same thing but in the second opamp feedback stage?
3. How I see in a early version of the Mockman, a 100k linear pot in line in the input.

[JackSkellington]

New little update. Nothing distortion pedal, again, but I'm trying to work soon about it. I'm wating some materials I ordered.
I just want to say, after the SHO as boost pedal, I just finished the IC Buffer in the 1590A box.

Meanwhile, I'm looking some mild overdrive, too. I can read all this thread where I got some suggestion about the distortion, but I found them not very distorted.

I just want to say that I will build it on veroboard, or maybe on perfboard.
Of course, I accept new suggestion!

[JackSkellington]

Hello, I don't know how much people are still following this thread, but...
Here's the original Smash Drive schematic:



I'm building the version without tone stack, of course.
I'm not sure if this pedal is never built by someone, but I'm trying.
First thing I did is to test it on the breadboard, and I got a little issue. The circuit had a lot of volume, I can hear the pedal even if my amp was at zero volume. And the sound was pretty fuzzy, a bit splatty and gated.
This is the second time I get something like this using a LM386 chip on my breadboard. I'm starting to think that the LM386 gets some problem with the breadboards, or with my breadboard.
Anyway, I draw a veroboard layout.



So I built it, and it worked. But I didn't include now the 100R in line to the 9v, nor the 100nF ceramic cap. Then I moved the 100uF a column at right. And the 10uF is soldered exactly there, but moved "asymettrically". This movement is because the space on the board.
The sound was ok, no fuzzy or weird.
I based the taper of the pots, or maybe just supposed those, on some information I found on ti or on other similar projects (for example the Lovepedal Black
Magic). But I could misunderstood something, I'm going to tell why.
I tried a 5k linear pot as Drive pot and 500k linear as Volume pot.
Testing the circuit I found that I got a jump loud volume when I open a little bit the Volume. And the Drive pot start from a overdriven sound at minimum setting until an aggressive and grit distortion as I expected a bit from this chip. But the distortion raise up quickly when the pot is almost all at clockwise. Too drastically.

I replaced the 500k linear pot with a 500k log pot, and the volume works a bit better. But I guess it's still too much loud. A casual flying resistor, 5.1k or 10k or 20k... I don't remember, between the output and the ground helps to tame the volume. I'll find out a good value.

About the the Drive control. When the pot is at minimum the resistance between lugs 1 & 2 and the lug 3 is high, so the distortion is low. At maximum setting there's no resistance between those lugs and the distortion is high. I need something that decrease faster the resistance between the lugs 2 and 3, so If I'm not wrong I need a rev log pot, 5k or maybe smaller?

The bad thing is that the two 9mm pots I'm ordered are linear.

[JackSkellington]

I left the Smash Drive into my building stuff.
And finally I made on breadboard the Mockman 2.0. It works fine and it's has a lot of gain. I tried a smaller resistor, about 22k, in the opamp feedback of the first stage, and actually it decrease the gain. I need to experiment more with it, but a pot log pot with a small resistor to set the minimum gain might be a good thing.
As Cx I used a 470pF, no problem with it.
The switch closed cut a bit of aggressive. Probably I'll let the the switch open, so without any switch for just one mode.
I bought a TLC2262 because ROG recommended it, but the sound was nice, but even funny. Not thin, nor muddy, but very nasal, like I had a wah pedal in heel position or a sort of narrow boosted peak at 1k frequency or something like that.  I hope I said it well.
I tried a JRC4558, and it makes to sound the circuit more balanced, normally, I'd say.

One day I'll try a protoboard layout.
I'm sorry about the TLC2262, I don't know why it sounds very very nasal. In case, I'll will use a JRC4558 or a TL072, maybe another usual opamp.

[gordo]

There are so many good ones out there.  I liked the demos I heard of the Acapulco Gold so I breadboarded it and it was horrible.  LOUD!!!

I'm a fan of the Dist+ but am spoiled rotten because of the Aion Aphelia.  It has all the bells and whistles that really make the circuit shine but it's 1590B.  You could incorporate a few of Kevin's ideas without the switching if you play around with the circuit a bit.

Bean's Fritter (Crowther Hotcake) is cool with a good gain range, and as mentioned the Snarkdoodle (Red Llama) based on the old Craig Anderton Tube-Sound Fuzz is a real nice change of pace.

[JackSkellington]

I have to say that every time I tried some LM386 based circuit on my breadboard, it every time sounded weird or broken or whatever. Built on the stripboard and those are ok.
I expected that Acapulco Gold is loud, probably, if I will buil it, I'll include the gain pot, too. Maybe we can adjust the final amount of the pedal, I guess we talk about it in this thread.

I prefer get on focus on this Mockman, I think I like it. I am just a bit sorry about the TLC2262 (it is most sexpensive than other opamp), I really didn't expect that weird sound. The only thing I can do is try do change some caps, maybe. I don't know, now. But, as I said, with the 4558 it's better.

[Willybomb]

I have to say that every time I tried some LM386 based circuit on my breadboard, it every time sounded weird or broken or whatever.

Yeah, I built the Stank/Smashdrive and it didn't really sound right to me.  Everything worked, but the dirt level wasn't really what I was expecting.  I can't find any problems... so, I dunno.

[JackSkellington]

I tried again the Mockman on the breadboard just like I did a few of time ago. It sounds right with the JRC4558 but now even TLC2262.
I can tame the distortion reducing the 1M resistor in the first gain stage.
It sounds very aggressive, high gain, and I like it. I don't like too much the decay of the notes, it's not quick, but the distortion abrupt too much suddenly. The things get worst if at low gain setting.
At the beginning I thought to have Volume and Gain control, letting the Modern Mode always On. Now I'm not so sure. I could build it like the stock version.

I guess my searching for a good little distortion will go on.

D*A*M circuit are pretty high gain, some ot them has small schematics, but those are almost all fuzz.
What D*A*M pedal is the less fuzzy and more distortion?

[JackSkellington]

Waiting some updating about the distortion circuit I'll choice I'm going to finish a Speaker Cranker (with master volume added) as overdrive 1590A pedal, after I built IC Buffer and SHO.

[DLW]

Lovepedal Jubilee. 386 based, so it probably won't sound great on a bread board. I just made a little PCB with proper ground plane and shielding, and it sounds fantastic.

[JackSkellington]

Yes, there are small layout of it, indeed. Or the Purple Plexi, too.
Both sounds great, and both have three pots, that is fantastic, but I think I want to try something with just two pots. I'll see what I can do with the Smash Drive (LM386 based on) and the Mockman. it's been a long time since the last tests so I have to test the boards again.
I remember, for some reason, at certain time the Smash Drive became a bit noisy. I liked the Mockman, but I had to find a good way to control the gain.

[JackSkellington]

Waiting the Mockman 2.0's perfboard is finished I'm back on my Smash Drive. I experimented with it a bit, and now is ready to box it up. Almost. (I need a file to file the protrusion of the 9mm pot).
First of all, the layout is the one I posted above, except the 100R and the 100nF ceramic cap are still missing on my board, but I can included it soon.
A 5k reverse log for the drive control works fine.
A 100k log for the Volume is already soldered, too.
I made just a pair of modifications. A 15nF (also a 22nF will be good) replaces the 4.7nF for a fuller tone. The output doesn't come directly through the 100nF output cap, but I added a 470k resistor to tame a bit the volume.
So, the output cap 100nF is moved a column right, a new 470k resistor in the column 10 goes from the row 2 to the row 1, and I made a cut track at its left to isolated from the 47uF. And the Volume 3 wire is now moved one row upper, of course.
Just it.

Meanwhile, I'll keep working on the Mockman 2.0, I still need some experiment to make a decent gain control: a potentiometer in front (that generically I don't like it too much), a sort of Pre-Gain control in the input across the ground or a potentiometer in the first feedback of the opamp.