Choosing Resistors?

[dfine22]

Hello,  I am attempting to build my first pedal (Firebomb).  I have modded a few pedals previously.  I am sure that this question has been addressed a thousand times before however which is the best choice for resistors ( metal film or carbon comp). Thanks

[night-B]

Usually métal film resistor 1/2w 1% are used in stompboxes. You can get  good deals on eBay!

[gtr2]

1/4 watt metal film 1% tolerance or 1/4 watt carbon film 5% tolerance is fine.  I personally use metal film.


josh

[madbean]

In general, I use metal for 100k and up. Below that I tend to use carbon film.

[stevewire]

In general, I use metal for 100k and up. Below that I tend to use carbon film.

Is there an advantage behind using carbon film?  I would assume the reason for using metal over 100k is because of the tolerances over that value?

[madbean]

Higher resistance means higher noise, hence the use of metal film. I use carbon film for most of the smaller values because that's what I have and the noise impact is lower, or so I've read. It just depends on what I'm building...I usually decide on the fly.

[stevewire]

Higher resistance means higher noise, hence the use of metal film. I use carbon film for most of the smaller values because that's what I have and the noise impact is lower, or so I've read. It just depends on what I'm building...I usually decide on the fly.

Interesting.  I knew that metal was supposed to be quieter.  I did not know that higher resistance means the possibility for higher noise.  Thank you.

[bigmufffuzzwizz]

[quote/]Interesting.  I knew that metal was supposed to be quieter.  I did not know that higher resistance means the possibility for higher noise.  Thank you.
[/quote]

Yes they would be quieter. Carbon Film are %5-%10 tolerance which means plus or minus the tolerance percentage of the value. So if you have a 10K ohm %10 carbon film it will be between 9K-11K which is normal for it. But a %1 metal film would be between 9.9K-10.1K!! Thats a huge difference and you will have a much more precise value with the metal film. But correct me if I'm wrong, even big pedal companies (for example EHX) are notorious for using whatever parts are available and cheapest to acquire. So go ahead and experiment. Nothing is wrong unless you don't like how it sounds!!!

[B_of_H]

i've been ordering 1/8w 1% metal films from mouser recently. 

[Ang3lus]

what about vishay 0.1% ?
would love to try a build built with those and normal metal film, just to see if there's a difference

[bigmufffuzzwizz]

what about vishay 0.1% ?
would love to try a build built with those and normal metal film, just to see if there's a difference

sounds like military components for building jets!

[Ang3lus]

my dad is an audiophile, has some really expensive parts in his amps

[CRBMoA]

I buy resistors. I like to buy 200 of a value at a time.

I measure every single resistor and cap i use, so I don't really care about tolerance. I will just slap a DMM on it, and I don't care if it does have nothing but red bands; if it measures closer to 20K, I'll just put it in that bin and keep looking.

I only sweat 1% tolerances when they are specified in the Build Notes or BOMs.