Rolling preamp tubes... Just flip on standbye?

[AdamBomb80]

Ive always heard from Mesa techs and other people it's ok to change a preamp tube when you flip in on standbye first. Is this correct? Of course you can change a power tube lik that but Im pretty sure Mesa techs say you can just flip amp to standbye and takeout old tube and replace with new one. And I'm only talkin about trying out one at a time of course. Like trying different tubes in just V1. U guys just flip on standbye to do this?

 

[bob-i]

Yep, just flip to standby and swap

 

[Tone_Terrific]

You don't even need standby.

 

[QRSS]

You don't even need standby.

yep....hot-swap to your heart's content.

 

[AdamBomb80]

Ok thanks guys. Was just making sure my tube knowledge wasn't rusty or what not. There's so guys over on MLP forums saying no no current flow, and turn amp off unplug cable .. Lol.. And way more than just one person are sayin that. Anyway I knew I could trust u guys. Cause I been doing alot of tube swapping or rolling whatever ya call, lately. THANKS

 

[sublimeaudio]

Yeah, with preamp tubes it's ok to pull them, even when not in standby.

 

[tmac]

I like to use standby, otherwise you'll probably get some pretty loud pop/crack noise through the speaker if you don't. Not that it would hurt anything except your speaker and your ears.

 

[Lance]

Sometimes when you pull one or more out just a little, you get some interesting sounds. I am trying to remember, but one of the Primus songs on like Tales From the Punchbowl (I think) Ler pulled a tube or two, and recorded the amp face up in a bathroom.

 

[Onioner]

Not really the healthiest thing for the tube. I'd let it cool. Doesn't take long.

 

[chillytc]

Not really the healthiest thing for the tube. I'd let it cool. Doesn't take long.

I agree with this. Also, may not be the healthiest thing for your fingers to be handling hot tubes.

 

[QRSS]

How can it hurt the tubes? If I hit standby and wait for them to cool down, i forget what they sound like, which is the reason I'm doing it.

 

[Onioner]

How can it hurt the tubes. If I hit standby and wait for them to cool down, i forget what they sound like, which is the reason I'm doing it.

First, They won't cool down on standby. That is the point of standby. Second, Tubes are far more fragile when hot. I should really amend my original statement. Might be the worst thing you could do to a tube short of smashing it. Tapping on it aint helping either.

 

[QRSS]

hmmmm......never had a problem with full-power swaps. Aside from fragile state when hot, how does it actually harm the tube?

 

[Onioner]

hmmmm......never had a problem with full-power swaps. Aside from fragile state when hot, how does it actually harm the tube?

There's no aside. Moving (including those pencil taps) a tube while hot is supposed to be freaking awful for the tube.

You won't necessarily know you have a problem either. The tube may just die a greatly premature death. Maybe not such a big deal when your using easily replaceable tubes, but a real drag if you're talking good old glass.

 

[tapehead]

v1 or v2 is one thing but I would not recommend playing around with phase inverter tubes when powered on, standby or not. I don't touch power tubes once they're powered on.

In fact, I prefer to do all rolling after powering down, standby amp or not. Tubes last a long time for me...YMMV

 

[Tone_Terrific]

There's no aside. Moving (including those pencil taps) a tube while hot is supposed to be freaking awful for the tube.

.

Recall that tubes have been used for car radios, in airplanes, tanks, ships, portable comm'n devices, etc, etc...popatubaphobia (remember those ads?) was rampant in the 70's about tv crt's but highly exaggerated on internet forums.
Your combo amp chassis rattles all the time, too.

 

[dinglehopper]

How can it hurt the tubes? If I hit standby and wait for them to cool down, i forget what they sound like, which is the reason I'm doing it.

If you let them cool down and you think one sounds better, play that one and move on.

If you let them cool down and you think they both sound good, play either and move one.

If you let them cool down and you think they both sound bad, get another tube or work on the setup.

it's tempting to get into microscopic sonic comparisons, but if you really need an instant a/b to tell the difference, does it really matter? (and any difference that small is probably only audible playing by yourself in a quiet room, anyway. certainly not at volume with other loud instruments or in a noisy environment)

IMHO . . . IMHO . . . IMHO . . .

 

[QRSS]

Lol....there's no sense in doing it if it didn't matter.

 

[dinglehopper]

btw, I'm totally guilty of doing silly things in the quiet of my house, trying to tease out minute sonic differences between speakers, pickups, etc.

this doesn't seem to happen so much when I actually have to work on playing music . . .

 

[blackba]

You can hot swap preamp tubes, but I prefer to power the amp all the way down and give the amp a few minutes to cool, before changing a preamp tube.