TSF/WHRL mods? technical questions

[Cliff Fiscal]

Took a look around the internet, but didn't find too much about it. There were some suggestions, but nothing definitive.

 

I've guitar to GGG WHRL kits.

 

The first one, I mistakenly put in the wrong resistor......if I recall it was the 1M R3 resistor.....which I substituted a 100k resistor.

 

The result was much less gain.......it ended up adding a bit of grit when the gain control was full up, and a little bit of sparkle.

 

I really liked it, but I wanted it to sound like a fuzz/dirt....put the correct values in there. Liked it okay, but switched it right back. Built another one for higher gain fuzz.

 

 

 

 

So my question is, can I swap this resistor for a pot?

if so, how do I go about that, and what would it actually be doing?

 

http://www.generalguitargadgets.com/index.php/projects/17-distortion/225-red-llama?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

 

 

Also, is it possible to add a tone control or a filter of some sort?

[Blakemore Effects]

Yup. You can absolutely switch it for a pot. Take a look at the schem, and look at how R8 is wired up. You'd just do the exact same thing where R3 is. Basically then you can control the amount of gain in each gain stage.

 

Adding a tone control is definitely a possibility too. The easiest thing to add would probably be a Big Muff tone stack. Ideally you'd experiment with putting it at separate spots in the circuit, but my guess for the best spot for the tone stack would be right after C6, and before the volume knob.

 

Best of luck, and let me know if you have any more questions.

[12string]

A pretty standard RC filter for the WHRL:

 

Or build a Big Muff tone stack on a pot, a la beavis audio:

 

[Cliff Fiscal]

A pretty standard RC filter for the WHRL: Or build a Big Muff tone stack on a pot, a la beavis audio:

 

Any benefit to either?

 

The RC filter just rolls off high end? The Muff allows for modification of both high and low freqs?

 

Do either effect the original tone of the pedal?

[macadood]

Mustang'd

[12string]

 

Any benefit to either? The RC filter just rolls off high end? The Muff allows for modification of both high and low freqs? Do either effect the original tone of the pedal?

 

 

Benefit...maybe, it's just a tone knob to fiddle with.

 

First filter will just roll of highs, yep. Muff is a combination of a high pass and low pass filter, values shown give the standard mid-scoop.

 

Either would affect the tone, you could make the tone section switchable for more options though.

[Kap'n]

 

Yup. You can absolutely switch it for a pot. Take a look at the schem, and look at how R8 is wired up. You'd just do the exact same thing where R3 is. Basically then you can control the amount of gain in each gain stage.

 

 

I'd probably put in a trimpot shunt, and give it an exteral toggle once you dial it in.

[Blakemore Effects]

I'd probably put in a trimpot shunt, and give it an exteral toggle once you dial it in.

 

Yeah. I was never big on trimpots. I don't like having to open up the pedal, if I can avoid it. The nice thing about the Llama is that since it normally only has 2 knobs, throwing an extra gain pot on the pedal should still be pretty simple, and you'd be able to balance things a bit easier.

[Cliff Fiscal]

Done.

 

1M resistor replaced with 1M pot.

It acts as a gain control for the first gain stage (FYI: I have no clue what I'm talking about.)

So it's volume, 1st gain stage and 2nd gain stage controls?

 

I used a linear pot and it seems touchy. goes from nothing to loud within a 1/4 turn.

 

As for the tones....I really dig the flexibility.

With the 1st stage set low and the 2nd stage off, it gets pretty thin and bright. Which in itself, isn't that useful.....minus being a nice boost sort of thing for a tubby distortion. Plenty of volume available in the design of the pedal anyway.

 

The cool part is that you can mix and match the 1st and 2nd controls for various flavors of the WHRL/TSF.

 

With the 2nd stage control cranked, you can dial back the 1st stage and remove some of the loose feeling of the standard pedal without this control.

It gets really crunchy and clear......which is fantastic. Kind of a AC/DC kind of gain, with a fuzzy edge.

 

Well worth using up a part in my parts bin.

[Kap'n]

Yeah. I was never big on trimpots. I don't like having to open up the pedal, if I can avoid it. The nice thing about the Llama is that since it normally only has 2 knobs, throwing an extra gain pot on the pedal should still be pretty simple, and you'd be able to balance things a bit easier.

 

I figured if you were going for a cleaner setting, you probably wouldn't need to tweak it much. Easier to deal with on-the-fly.

 

Nice going Gas King! I love the TSF/RL

[Cliff Fiscal]

I'd post pics, but it was one of my earlier builds....and was pretty "spaghetti"....plus I had to make the new large pot fit.

 

Here's the other one I made (the mistake one....low gain, brilliance boost)......needs some zip ties for more neatness.

My attempt at cleaning up the layout. Not perfect but better.

 

[Blakemore Effects]

Done. 1M resistor replaced with 1M pot. It acts as a gain control for the first gain stage (FYI: I have no clue what I'm talking about.) So it's volume, 1st gain stage and 2nd gain stage controls? I used a linear pot and it seems touchy. goes from nothing to loud within a 1/4 turn. As for the tones....I really dig the flexibility. With the 1st stage set low and the 2nd stage off, it gets pretty thin and bright. Which in itself, isn't that useful.....minus being a nice boost sort of thing for a tubby distortion. Plenty of volume available in the design of the pedal anyway. The cool part is that you can mix and match the 1st and 2nd controls for various flavors of the WHRL/TSF. With the 2nd stage control cranked, you can dial back the 1st stage and remove some of the loose feeling of the standard pedal without this control. It gets really crunchy and clear......which is fantastic. Kind of a AC/DC kind of gain, with a fuzzy edge. Well worth using up a part in my parts bin.

 

Awesome, man! Congrats. Always so rewarding when something you do works on the first try. If the sweep bugs you, you could try swapping out the 1M linear pot for a 1M logarithmic pot. Just a thought! Congrats again though.

[Cliff Fiscal]

Awesome, man! Congrats. Always so rewarding when something you do works on the first try. If the sweep bugs you, you could try swapping out the 1M linear pot for a 1M logarithmic pot. Just a thought! Congrats again though.

 

I figured, I just used the 1M pot I had in the parts bin.

 

Was using it with a Super Reverb and I was getting some really nice tones....almost reminded me of a pushed Tweed at higher gain settings and a broken up Deluxe at lower settings.