ELS
Active member
Every mention of this is like "oh yeah ya know, tube rolling, your everyday term!"
what is it?
what is it?
yeah and it isn't intuitive as well, a better term could be tube substituting or just calling it tube swapping, although that's more specific to swapping between the same type of tube.I hate that term , you'll often see people that think they can swap out a 12ax7 for a 12au7 but chances are it wont be right without other components changes . You could easliy exceed one or more of the tubes maximum ratings in which case reliabillity might become an issue .
Yeah I don't get when people say that definitively there's no audible difference...There has been a few times I swapped out op-amps with other types with the same pinout and got an improvement in noise , but it perhaps effected other parameters such as the load presented to the source in a negative way . In the case of direct connection of a high Z magnetic pickup input a lower load will change the sound of the pickup , then again if you happen to have a buffer in an effects pedal following the pickup the input impedence difference might be of no consequence at all .
Having said all of the above , if someone finds a substitute part that ,for them gives a subjective improvement , even if its not technically correct , then why not .
Opamp supplies are fairly standard , dual rail 15 or 18 volts , so in any case things probably wont blow up . Tubes vary widely in many respects , gain , supply voltages and currents and abillity to drive lower loads . Swapping out a 12ax7 for a 12at7 in the LTP phase invertor of a guitar amp will cause a change in the sound , for several different reasons , it might well give an improvement in the ear of the beholder , but thats not to say its always appropriate to use those tubes as equivalents in every circuit .
Anyway welcome to GDIY ELS ,
its a good question you asked ,
Im certainly looking forward to hearing from more of our contributors on the subject .
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