V4 / 5 1.5K grid resistor wattage

[Ron Worley]

For some reason I have this resistor listed as 2W metal film (Vishay BC). Looking at the pics of Franny and the undocmented '90 Wreck (see attached pic), they appear to be regular 1/2W carbon film...

I searched the board, but no joy. Can someone help me get this right?

Thanks in advance,

Ron

[Bob-I]

The grid stopper wattage is not important. 1/2 watt works fine. I use 1 watt just because I use 1 watters for signal everywhere.

[dartanion]

The reason for a high wattage metal film is for noise reduction. Check out Aiken's site for the article on resistor types.

[skyboltone]

The grid stopper wattage is not important. 1/2 watt works fine. I use 1 watt just because I use 1 watters for signal everywhere.

Bob, I take it you've given up on RN-65s. What are you using for 1 watt matal films?

Dan

[Ron Worley]

So there is some disagreement here...

Should it a higher wattage than 1W? I agree metal film is quieter, I need to read up on Aiken's site on exactly what's going here....

I had ordered 3W metal film.. but the Franny pics threw me off, hence the question. They look regular old 1/2 carbon film to me...

Ron

[jjman]

Normally there should be no current flowing thru the grid stopper so I'm not clear on how the type would affect noise level. I guess the voltage swing can be corrupted by "noisy" resistors?

Using a higher wattage resistor in a location subjected to heat is a good idea. Such as across a tube socket with downward facing tubes. I've read that a 1/2watter is more susceptible to heat damage than a 1-2watter.

[dartanion]

Here you go:

http://aikenamps.com/ResistorNoise.htm

[Bob-I]

The grid stopper wattage is not important. 1/2 watt works fine. I use 1 watt just because I use 1 watters for signal everywhere.

Bob, I take it you've given up on RN-65s. What are you using for 1 watt matal films?

Dan

No, I haven't given up on RN65's, but they're only for plate loads on Dumble style amps. Everything else I use 1 watt CF.

[Richie]

seems as years go by, the newer 1/2 CF are smaller in size than the ones of years ago. Which may look in size very close to a 1 watter of today.
Sometimes too, the brand you use might be a different looking size in the same wattage.
1/2 CF should be fine,and as they attach to the tube pin,then the wire to the end of the resistor. So its sticking up in the air,the bigger resistors might come closer to the output jacks etc.. So the 1/2 watters might be the best to use in this section,and as was posted, this is what was used in the real wreck,but the 1 watters we have today would also work. I wouldn't use anything bigger.

[jjman]

Here you go:

http://aikenamps.com/ResistorNoise.htm

".......If no current (AC or DC) flows in the resistor, the noise is equal to the thermal noise......"

" the thermal noise of a 1K carbon resistor is the same as a 1K metal film; it is independent of material..."

Sounds like a grid stopper's material isn't going to affect noise. Unless it has current flowing thru it, which is not normal (I think.)