Resistor Failure for Fender Bassman 59 Reissue LTD
Hey Skip,
I am looking to purchase a Fender Bassman 59 Reissue LTD. I watched "The Bassman Chronicles" to learn as much as I can. Mark and David mentioned getting the resistors related to the preamp valves upgraded from 1/2 watt to 1 watt because of the voltage from lowering the gain with tube changes to V1- 12AT7, V2-12AY7, V3 12AU7. I'm a little confused as there seems to be some debate about how necessary it is to upgrade the resistors. Is it expensive and difficult to upgrade the resistors? It sounds like a 12AU7 in V3 position creates the most stress to the resistor. Is there a higher gain tube set up that is still lower than 12AX7's that doesn't create threat to the resistors?
Thanks for the advice!
Hey Skip,
Thanks so much for the response on this. I really appreciate it!
Hello Erik- Sorry for the slow reply. I think you will find that many people have succesfully used a lower-gain tube line-up in their RI Bassman amps without changing the resistors. On the other hand, the stock resistors actually ARE borderline in wattage for the amount of current being carried, and often need replacement. I would certainly consider one-watt resistors to be a good (but not essential) upgrade.
Changing parts on a printed circuitboard isn't easy, so I would say that $75-100 would be a reasonable labor cost.
If you stay away from 12AU7s, you should be less likely to have a problem with the stock resistors.