Which Wattage Resistor is Best for a Noiseless Filter Design?

[m718]

In a filter where 1/4 watt resistors is enough would the filter be less noisy if I use 1/2 watt or more or should I use the least wattage resistors needed?

 

[berkeman]

In a filter where 1/4 watt resistors is enough would the filter be less noisy if I use 1/2 watt or more or should I use the least wattage resistors needed?

The size of the resistor will not generally affect its noise. The construction may affect it (carbon composition versus metal film), but I haven't looked at that in a while.

 

[berkeman]

Did a quick google search, and found this interesting article on resistor noise and composition:

http://www.aikenamps.com/ResistorNoise.htm

.

 

[Mike_In_Plano]

You have two common catagories of resistor composite or metal. With surface mount parts, the composites are your referred to as thick film.
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Metal will be called out as "thin film," metal film, or wirewound.
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When you have little to no current flow through the resistor, thermal noise will likely dominate, and you're not likely to see a benefit of one over the other.
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However, when you apply current, composite resistors become very noisy due to the irregular grains and contact transitions. Metal resistors remain very quiet though.