Retubing... How do I know when ???

[Benkenove]

Hi Guys,

Well, I guess this has been coment before, and that it may sounds a little stupid, but I need to ask it...

The question is simple... :$

Ho do I know that I MUST change the tubes of my herbert ???

I mean:

1.- When should I change the preamp tubes ???? (this is one of my main doubts)
2.- and when should I change the poweramp tubes (when I see one of them not-lightened ?? or when ? )

My herbert hasnt got the failure tube leds (It's a pity cause I'm one of those stupid ones that would need it )...

And another question...

If I change any tube... would be better to CHANGE THEM ALL together ??? preamp and poweramp tubes ???

I know many people would answer... FOLLOW YOUR INSTINCTS ... or... use your ears... but ok... is there any other way to know it ?? and to know if an specific tube is off ???

Thank you so much for your patient and I hope someone can help me .

 

[itsme]

After I get the preamp tubes I want for the tone I like, I only change preamp tubes when they go bad. When the amp gets noisy or microphonic, I find the suspect preamp tube by isolating the channel it affects, or by tapping on it with an un-sharpened wood pencil. I replace it with the same kind. There is no need to replace a preamp tube unless it sounds bad. They can last a very long time (many years), or short time depending on the tube.

You should replace a pair of power tubes, if they crap out, blow a fuse, etc... Replace the whole set when it starts to sound bad. Like if you start to notice the amp is very dark/muddy when you first turn it on and then slowly it gets brighter. Then it starts to take longer to brighten up the next time. Eventually it won't brighten up. It will also seem more distorted and unclear. I find EL34's last between 6 mnths and 1 1/2 yrs depending on quality of tubes and how much you play. 6L6, 6550, KT88 type tubes usually last 1 1/2 to 2 1/2 yrs. They're more sturdy/durable.