- #1
Planobilly
- 440
- 105
Hi Guys,
I am looking for a high level overview concerning resistor noise and how to reduce it. I have read the following general statements.
Carbon comp resistors are rated at 0 db. I read this somewhere.
Vishay metal film resistors MIL-R-10506 are rated at -40 db http://www.vishay.com/docs/31027/cmfmil.pdf
The idea is to lower both the current noise and the Johnson-Nyquist noise in a typical guitar amp.
I assume the following.
1. Use low noise resistors (easy to do)
2. Reduce the resistance value to the minimum that does not cause other issues...most important on preamp stages (not so easy to do)
3. Lower the resistor temperature ( just how to do that and by how much in a practical way I am not sure how to do)...I assume the ambient temperature in a closed chassis to be around 150 F depending on the type and number of tubes. (lowering the temperature could range from a cooling fan to pretty complex other lower temperature methods)
Ideas? Methods used in other equipment?
Thanks,
Billy
I am looking for a high level overview concerning resistor noise and how to reduce it. I have read the following general statements.
Carbon comp resistors are rated at 0 db. I read this somewhere.
Vishay metal film resistors MIL-R-10506 are rated at -40 db http://www.vishay.com/docs/31027/cmfmil.pdf
The idea is to lower both the current noise and the Johnson-Nyquist noise in a typical guitar amp.
I assume the following.
1. Use low noise resistors (easy to do)
2. Reduce the resistance value to the minimum that does not cause other issues...most important on preamp stages (not so easy to do)
3. Lower the resistor temperature ( just how to do that and by how much in a practical way I am not sure how to do)...I assume the ambient temperature in a closed chassis to be around 150 F depending on the type and number of tubes. (lowering the temperature could range from a cooling fan to pretty complex other lower temperature methods)
Ideas? Methods used in other equipment?
Thanks,
Billy