Resistor value and type

[JPGraphX]

Hi!

I'm building a Chimaera and some resistors are carbon and some metal film. On my first build, I forgot to put metal film where it is suppose to. I bought some metal film but there is some value that I don't have.

Example: I got 1.5k metal film, but no 1k. Should I put a 1.5k metal film or I should keep 1k carbon film. What should be closest to original build?

(I want to know want influence more, value or type)

Thanks!
JP

[JPGraphX]

I have 7 metal film to change on 30 resistors total, should I replace them?

[JPGraphX]

They are Carbon Film not Carbon Composition.

[JPGraphX]

Anyone?

[pappasmurfsharem]

Depends on how close

Carbon film I think has a 5% tolerance, while metal film has 1% tolerance.

So for instance with the 1K

1K Carbon +/- 5% = 950R -> 1050R

1.5K +/- 1% = 1.425K -> 1.575K

Thats almost thats a 150% difference.

Granted it depends the circuit might not be picky, but the carbon film will be closer in this instance.

[JPGraphX]

If I sont replace the resistor that should be metal film, should I expect à significative différence on sound?

[pappasmurfsharem]

If I sont replace the resistor that should be metal film, should I expect à significative différence on sound?

Supposedly they are supposed to be more noisy but I doubt you will notice.

[alanp]

Carbon COMP is quite noisy, Carbon FILM is pretty good, and Metal Film is excellent for low noise.

Mojo or no mojo, I never use CC resistors in pedals. (My 5E8A amp came with CC resistors, to be period correct, mostly went with them... even then, I swapped the plate resistors for CF, to reduce noise.) They also drift in value over time.

You're usually pretty safe to use CF or MF interchangeably. Where the value is important (for frequencies, etc), or you're working with a lot of gain, it's better to stick with MF.

[deadastronaut]

i built 2 identical hi gain fet distortions one with carbon, one with metal....

any difference?...not audibly at all. ...the blue just looked better.

[duck_arse]

they might look better, but we all know they are harder to read ....

as I understand it, the noise produced in resistors is high and white, hissing like. and is dependant on the resistance value, the higher the worser. and is worse in the carbon resistors.

if the carbon resistors aren't in the audio path, or biasing something, they are fine.