Question about a schematic I found

[Hemmel]

Hey guys, please tell me if I'm doing something wrong by posting this link :

Boss DS-1 Schematic : http://www.freeinfosociety.com/electronics/schemview.php?id=130

My borther wants me to try to build this, however I'm a bit confused. What's the meaning of the two sections (dotted lines) ? Is it "one or the other" ? To taste ?
As for the 500KC pot, can I just use a 500KA pot and reverse the lugs (I think not, because audio pots are logarithmic, right ? so the curve wouldn't be the same in an reverse audio pot than an inverted audio pot ? I'm just not sure here). I have all the parts except this reverse audio pot... I'm trying to find an alternative...
The pot in the middle says "50K" only. I'm guessing I can put a linear there ?
The diodes aren't specified but I'm guessing any like 1N914 or 1N4148 can do ?

Thanks and, again, please tell me if it's a "no-no" to post links like I did.

[Govmnt_Lacky]

My borther wants me to try to build this, however I'm a bit confused. What's the meaning of the two sections (dotted lines) ? Is it "one or the other" ? To taste ?

Correct. Just different ways to include the Tone stack.

As for the 500KC pot, can I just use a 500KA pot and reverse the lugs

Yes you can. Keep in mind that when you do this, the control will work in reverse of the original. So if you get more distortion when it is turned clockwise on the original, yours will get more distortion when turned COUNTER clockwise. But it will work.

The pot in the middle says "50K" only. I'm guessing I can put a linear there ?

The Tone pot (in the dotted lines) is labeled as a Linear pot 50KB. The Output pot is a 50KA log pot.

The diodes aren't specified but I'm guessing any like 1N914 or 1N4148 can do ?

Correct!

Keep in mind that the schematic you linked DOES NOT show the "complete" power section of the pedal. There are plenty of schematics for this pedal to be found. Do a little more digging before building.

Good Luck  

[Govmnt_Lacky]

My borther wants me to try to build this, however I'm a bit confused. What's the meaning of the two sections (dotted lines) ? Is it "one or the other" ? To taste ?

Correct. Just different ways to include the Tone stack. It is one or the other AND it is to taste. Which ever you prefer.

As for the 500KC pot, can I just use a 500KA pot and reverse the lugs

Yes you can. Keep in mind that when you do this, the control will work in reverse of the original. So if you get more distortion when it is turned clockwise on the original, yours will get more distortion when turned COUNTER clockwise. But it will work.

The pot in the middle says "50K" only. I'm guessing I can put a linear there ?

The Tone pot (in the dotted lines) is labeled as a Linear pot 50KB. The Output pot is a 50KA log pot.

The diodes aren't specified but I'm guessing any like 1N914 or 1N4148 can do ?

Correct!

Keep in mind that the schematic you linked DOES NOT show the "complete" power section of the pedal. There are plenty of schematics for this pedal to be found. Do a little more digging before building.

Good Luck  

Sorry.. tried to edit the post to make it more understandable. EDIT is in RED

[Electron Tornado]

That's not a DS-1. It's more like an MXR Distortion + with tone control added.

The dotted lines are a bit confusing. Pretend there is no dotted line around the 0.001uf capacitor. Now look at the 12k resistor, 50k potentiometer and the two capacitors that are together in the circuit. Now look at the similar group of components inside the other dotted line. You can use either the circuit that is already part of the larger circuit, OR the one inside the dotted line.

To make it simpler, you can eliminate that part of the circuit, except for the 12k resistor (you can use 10k there as well), and you will have a Distortion + or a DOD OD250. Take a look at these schematics:  http://www.freeinfosociety.com/electronics/schematics/audio/dodoverdrive250.pdf and  http://www.freeinfosociety.com/electronics/schemview.php?id=562

The diodes in the Distortion + were 1n34 germanium, but you can use just about any diodes there. Try different combinations and use a switch to make them selectable. Here are a couple of articles to read: http://www.muzique.com/lab/warp.htm   and   http://www.muzique.com/lab/sat.htm

Read, learn, build, have fun!

[Electron Tornado]

By the way, Govmnt_Lacky, excellent quote at the bottom of your posts!

[Hemmel]

Thanks Govmnt_Lacky !

The 2 Tone stacks weren't clear to me. I thought the left section replaced only the .001 cap in the other section... now thanks to you, it's clear.

As for the power section, I'm going to breadboard this first. I'm guessing the 9V goes on top of the 10K resistor, as well as pin 7 of the 741 (ground pin 4).
I also just realised that I'm not sure if I have any 741's, but I do have TL071's. Might try with this one instead.

[Hemmel]

That's not a DS-1. It's more like an MXR Distortion + with tone control added.

I kind of thought so... I have another schematic for the DS-1 and it's full of ICs and transistors I've never heard of. When I got this schematic I was really excited because the parts were all known to me (also I almost have them all at home).
I'll ask my bro if he still wants me to try it (he really wants to get that Nirvana sound, and he's desperate for a DS-1).

Thanks a lot for the info and the links, ET ! I'll go read those right away.

[Govmnt_Lacky]

The diodes in the Distortion + were 1n34 1N270 germanium...

Fixed 

[Electron Tornado]

The diodes in the Distortion + were 1n34 1N270 germanium...

Fixed 

Oops! Thanks!

[midwayfair]

and he's desperate for a DS-1).

I'm confused.

This is a pedal people practically GIVE away. It's probably the most common pedal on the planet.

[Govmnt_Lacky]

It's probably the most common pedal on the planet.

2 words..... Tube Screamer 

[Hemmel]

This is a pedal people practically GIVE away. It's probably the most common pedal on the planet.

He's my brother and he wants to encourage me. I think he already has a Boss DS-1 but he'd like to have a "Hemmel-built" DS-1. I appreciate it  

Maybe "desperate" wasn't the right word to use. I should've said my brother is "a sucker for a DS-1".
I know the grammar, I know the vocabulary (most of it) but I still have trouble expressing thoughts in English....

[Tony Forestiere]

I think this is what you are looking for. FET flip-flop switching omitted:



Link: http://www.diystompboxes.com/pedals/schems/BssDS1mod.gif

edit: added link for better picture resolution.

[Hemmel]

Thanks, Tony !!!
I'm still a beginner here and I'm not sure which transistors to use, can I just put in any NPN ?
Can I substitute the TL061 for a TL071 ? They're both single opamps and their pinouts are the same...

I ask these question because I'm not clear on voltages and current and what's needed for different parts. For example, the schematic Tony provided shows for a TL061 but if I put a TL071, would I need to change anything else ? Like lower some resistors to give more current ? Same thing goes for NPNs, if I use 2N3904 instead of 2N5088, would I need to change anything in the resistors/caps values ?

Thanks again guys, the learning curve is steep but I'm having a lot of fun !

EDIT : Ok I just read I could replace the 2SC2240's with 2N5089's. I noly have 2N5088's at home (apparently they have a lower gain).

[Electron Tornado]

I'm still a beginner here and I'm not sure which transistors to use...

Since you have most of the parts for a Distortion +, why not breadboard that and see how your brother likes it. It's a very simple pedal to build. You can change diode combinations and he can see what he likes.

If you don't have a 500k rev log potentiometer, what pots do you have on hand?


I'm kind of wondering, and hopefully someone else will comment - has anyone built a Dist + or OD250 using the gain control circuit from a ProCo Rat? The reason I ask, is that Hemmel may already have the parts to do it, or they may be easier for him to get.

https://www.generalguitargadgets.com/pdf/ggg_rodent_sc.pdf?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

http://www.generalguitargadgets.com/diagrams/ratc.gif?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

[Hemmel]

Since you have most of the parts for a Distortion +, why not breadboard that and see how your brother likes it. It's a very simple pedal to build. You can change diode combinations and he can see what he likes.

That's a very good idea. Although I am pretty close to having all the parts for the schematic Tony provided, I'll still have a look at Distortion +. If bro doesn't like it, maybe I will !

If you don't have a 500k rev log potentiometer, what pots do you have on hand?

I have no rev log pots on hand. I have linear and log 500K pots (and other values such as 1M, 100K, 50K, 1K). I thought I could just use a log pot and reverse the connections to get a rev log so I didn't feel the need to buy any...

[Electron Tornado]

For breadboarding, use one of the 500k pots you have. If you or your brother like how the circuit sounds, then go ahead and get a reverse log 500k.