Silly question - Resistor, Cap or... nothing?

[stand]

Hi everyone!

Maybe such questions would sound too trivial for most of you experienced pedal diy-ers, but I really had to put it here... I decided to make Liquid Drive, another Dist+ clone (it's mostly similar to Ross Distortion). Liquid Drive author had both versions of Ross (Tan and Black) in mind and he also used some better parts and slightly different values to improve sound of this pedal.
If you want too see the Liquid Drive schematics you can see it here:
http://fuzzcentral.tripod.com/liquid.html

Anyway, here is my question:

- On Liquid Drive the first part on input side is 1M resistor to ground.
- On original Ross schematic you can see 1nF capacitor on the same position.
- On DOD250/308 there you can't see any resistor or cap to ground on this place.

This made me feel so confused – I want to make Liquid Drive but I am not sure what I should put there and what is exact role of this resistor/capacitor. If it's really necessary why it is missing on DOD 250 overdrive? 

[Seljer]

Put both of them in there

1M resistor: prevents the clicking sound when you switch the pedal on/off
1nF cap: along with the 10kohm resistor infront of the opamp it forms a low pass filter that cuts off the radio frequencies

[syndromet]

Go with the 1m pot. This is a pulldown resistor, and will help you avoid popping from the switch. It also affects the impedance of your signal.
If you browse through a lot of schems, you'll see most o them have a big resistor to ground first in line.

I'm not sure if I got this correct, so might want to wait and hera what the experts say...

[stand]

Thanks folks!

It seems that I should put both cap and resistor to ground there...

Though I still don't understand why they ommited to put anything like that on DOD 250 and 308, I believe that they knew what they're doing... I can't believe they tried to spare a resistor or cap, I don't think it could make some considerable gain increase this way...

I also expect to see what experts on this forum say about it... 

[burnt fingers]

My bet is DOD did omit these things for cost savings.  They are convinience parts. A little anti pop rsesitor and a small cap to filter out radio frequencies you may or may not be getting through your pedal don't effect the pedal as a whole.  That's two less componants you have to pay for and two less componants to solder getting the board in the box a minute quicker.  When your building tens of thousands of boxes, it will add up.

Scott

[stand]

To burnt fingers:

So, "the big numbers law" is what we are talking about here... I understand it now. I am not quite sure how it would raise price of pedal (if DOD decided to include these two parts there) but if we talk about thousands of units then it probably could be considerable ammount (and time IS money, isn't it?). So, thanks for your explanation. If I ever decide to make thousands units of any pedal model I'll certainly include it (joke, joke...) but while I keep it at single unit level I really don't have to worry about cap or resistor less or more. Probably such a greedy attitude (less parts=higher income) is good opportunity fot all these companies/people who make all these pedal mods and tweaks...
So, that's it...

Thanks to all of you, again...

Dejan

[calpolyengineer]

DOD wouldn't increase the price of the pedal because they have a certain price-point they would aim for. Instead they would have to eat the extra cost of the components out of their profit. Over thousands of units, that would be a considerable loss for them.

-Joe

[stand]

 
Yes, it was my mistake, I must admit it... I forgot to add word "production" there so this sentence should be "I am not quite sure how it would raise production price of pedal (if DOD decided to include these two parts there)...". But, from other my words it's easy to see what I tried to say: "Probably such a greedy attitude (less parts=higher income)...". So, apology goes to all of you who ever saw my previous post because I was not quite precise about word "price" there – I know that this word usually represents the selling price so this could mislead you.

Thanks for your remark, Joe!  I hope that now I succeed to explain what I've tried to say... (English is not my mother language, it's something like "DIY English" and it's really on shaky legs, if you know what I mean...)