Adding power supply socket to FF

[DJPsychic]

Going to install a power supply jack, along with the battery snap, to my next NPN germanium FF build.

Do I need to add any filtering to circuit board?

[patrick398]

Probably wouldn't hurt to have a small series resistor plus large cap in parallel (smaller cap also in parallel if you want)

[DJPsychic]

Probably wouldn't hurt to have a small series resistor plus large cap in parallel (smaller cap also in parallel if you want)

What values would you recommend?

And is it absolutely a must or just a precaution?

[DJPsychic]

Only ask because space is kind of limited on my current layout. If it involves too much moving around, may just leave out. I've heard germaniums don't like power supplies. But would be nice to have the option.

Also looking at pedals like the Sun Face, I don't see any filtering

[patrick398]

Usual practice would be a 47-100R series resistor, 100u and 100n cap in paralell. Not sure why germaniums would not like power supply but happy to be shown otherwise

[DJPsychic]

Usual practice would be a 47-100R series resistor, 100u and 100n cap in paralell. Not sure why germaniums would not like power supply but happy to be shown otherwise

Excellent thank you

And Yes just something I've read, can't speak on it personally.

Could I get away without the added filtering or is it required?

[j_flanders]

And Yes just something I've read, can't speak on it personally.

It's not that they don't like power supplies but some people find the circuit sounds better with a certain type of battery.
https://www.diystompboxes.com/smfforum/index.php?topic=62730.msg493854#msg493854

Could I get away without the added filtering or is it required?

It's not required, it will work without the filtering.
However, the power from your adapter might not be 'clean' enough which you may hear as hum.

[DJPsychic]

It's not that they don't like power supplies but some people find the circuit sounds better with a certain type of battery.
https://www.diystompboxes.com/smfforum/index.php?topic=62730.msg493854#msg493854

It's not required, it will work without the filtering.
However, the power from your adapter might not be 'clean' enough which you may hear as hum.

Thank you (again) for clearing that up man. I'm gonna roll with out it for the time being.

Does the filtering effect tone? Spent a lot of time dialing it in 

[bluebunny]

Does the filtering effect tone? Spent a lot of time dialing it in 

The filtering is for the incoming power, not audio.  It won't change your tone.

[patrick398]

Here's a good read about power supply and filtering.

https://www.mrblackpedals.com/blogs/straight-jive/7475792-you-want-the-truth-you-cant-handle-the-truth-more-than-you-need-to-know-about-power-supplies

As Marc says, you're just filtering the power, not audio. Your wall wart or isolated power supply or whatever is taking AC from the mains, stepping down the voltage and rectifying it which means converting it from AC to DC. This process is not perfect and varies with the quality of power supply.  Basically the filtering we put in place attempts to smooth out any inconsistencies in the power supply which might create noise or problems in circuit performance.
I'm sure it's WAY more complicated than this simplistic view, but that's above my pay grade

[bluebunny]

Yes, Patrick's quite right to add some explanation.  My response was a little lite on actual information.      It's worth saying too that it's not just the gorgeous sinusoidal AC nature of the power origins that you're trying to hide, and render as perfect DC, but also any amount of other crud that may find its way down that bit of power flex to your pedal.

[patrick398]

...but also any amount of other crud that may find its way down that bit of power flex to your pedal.

I think you need a plumber

[DJPsychic]

Yes or an Otolaryngologist 

[duck_arse]

with a tache, no less.

[mozz]

No filtering, you want carbon zinc battery or a high impedence power supply. The audio modulates on the DC.