Rule of thumb... how many spare tubes to bring for gigs?

[dgt49ers]

Hey guys -

I switched from SS to tube amps a few years ago and I've never had a failure at a gig. But lately, I'm getting a bit paranoid (is it age?) and just wondering what the Boy Scout approach would be for spare tubes. Thoughts?

[CL400Peavey]

None, unless they are in another amp. A back up amp is the way to go. Tech time at a gig to replacing tubes is not.

[alembicguy]

Originally Posted by CL400Peavey

None, unless they are in another amp. A back up amp is the way to go. Tech time at a gig to replacing tubes is not.

This^^^^^^^^^^^^^^^

[Nephilymbass]

Just bring a solid state as a backup. I only had a tube go down every couple years. My issue with it was any replacement tubes I tried didn't sound the same so I switched to a rackmount sans amp for a similar tone.

[LiquidMidnight]

Originally Posted by CL400Peavey

None, unless they are in another amp. A back up amp is the way to go. Tech time at a gig to replacing tubes is not.

Bingo. Had a microphonic pre tube when I got to the gig a few weeks ago. I just plugged my BBE preamp that I keep in my cable bag into the pre-in on the amp to play the gig. Most tube amps, whether they're rack mounts are in wooden head boxes require a bazillion screws to loosen to get to the tubes. As has been stated, the time before a gig generally is a bit hectic to be swapping tubes...unless you're playing one of those venues that requires you to show up two hours before the doors open to get your sound check done.

I don't necessarily think you need a spare amp per se (although I have started to keep a spare amp in the band trailer), but you should have a contingency plan, whether that's a DI box or a small preamp that you can send to the house like the Tone Hammer.

[dgt49ers]

thanks guys... looks like I need to get through tonight and get on the lookout for a SS backup (only own tube amps now)

[B-string]

I have brought spare tubes before. If you are an experienced tech and want to spend your breaks fixing the rare failure at a gig then bring spares. A backup plan is more advisable for the RARE failure at a gig. Times I have used spare tubes at a gig ZERO. Times I have seen a failure at a gig that prevented a tube amp from being used, once in over 40 years.
Times I had a SS amp fail and could not be used, four, and that was with one SS Bassman (I hated that amp!).

[LiquidMidnight]

Also, keep in mind that sometimes a tube failure will burn up a screen grid resistor, so replacing the tube in that socket is pretty pointless until you get that resistor replaced.

[JBNeedsBeer]

At the very least, you should bring fuses, if not a ss backup

[ngh]

any old thing will work as a backup. I use a Randall 300 as my backup (which is a piece of ****) and I figure that when a tube fries on my sunn i will be so angry and upset that tone will no longer matter .

kidding.
but i really do use a randall 300 as my spare. strangely enough doesn't sound all that bad though I feel like it should. does way as much as a tube amp though.

[Jim C]

I always have a 12AX7 in my gig bag whether I am using tubes or not (also always carry a spare bass head).
The 12AX7 is also for the guitards; I've seen a pre-amp tube go bad that caused no other problems and was easily changed. Seems to me that if a power tube dies without warning, there usually is some other component carnage that goes with it.

I use a small presecription container with a piece of foam at the top and the bottom; tube floats between the foam and travels well.

[beans-on-toast]

It really depends on the amp. Some allow easy access and a change takes no time at all. Other amps require a lot more work to access the tubes.

I do carry spare cables, strings, some tools, a speaker cabinet breakout box, cloth, bandaids, etc. where ever I am with my gear.

I had a 12AX7 blow in a small Boogie amp and had a replacement on hand that saved my bacon.

[rodl2005]

None! Since 1978, I've used all tube amps & never have needed a spare tube. (that I can remember)
Tho a spare 12ax7 ain't a bad idea, & these days I carry a micro-class D- amp in a bag, just coz it's SO easy.

[Passinwind]

Originally Posted by LiquidMidnight

Also, keep in mind that sometimes a tube failure will burn up a screen grid resistor, so replacing the tube in that socket is pretty pointless until you get that resistor replaced.

Been there, done that...on a set break.