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Replace tubes yearly?

I just watched a Paul McGowan video (PS Audio) about the wisdom of leaving your gear powered on all the time. I get that. He also said that vacuum tube gear is the exception and not to leave it on all the time. I get that too.

But he also mentioned that it didn’t make a huge difference since you probably should replace your tubes every year.

Is that true? I have an Audio Research LS-16 tube preamp from the late 90s or early 2000s. I don’t think the tubes have ever been changed. I’m not really a ’tube’ guy but this unit was given to me 6 or 8 years ago. As far as I know these tubes are original.

At one point I got curious about the different sound quality potential of different tubes and another Audiogon member lent me a set of tubes to try out. I could definitely tell a difference but did not think the new ones sounded better than the original ones. I mention this because at that time the original tubes were quite old and still sounded quite good. And still do.

So, bottom line is, is there any real need to replace tubes on a schedule of some sort. Maybe its different if it is an amp versus a pre-amp?

 

n80
ghdprentice
7,222 posts
 

Amplitrex AT1000 is the tube tester to buy.

 

https://amplitrex.com

 

Tests multiple variables on most audio tubes.

n80 OP
2,133 posts
 

As OP I have nothing to add to the great technical advice given in this thread.

I do wish I could remember which Audiogon member sent me those tubes a few years ago. It was a very gracious, and trusting, thing to do for someone he’d never met anywhere but here.

I will also say that in the last year or so I get a little bit of speaker hum when I first turn my system on. It goes away to complete silence after about 5 minutes. This is an old system so I guess it could be anything but it makes me wonder if it might be a tube. I may get a back-up set just to test it.

But, I confess that I absolutely hate messing with my system, fooling with cords and pulling components out. I guess some people enjoy that but I don't.

larryi
4,093 posts
 

I have, and like, the Amplitrex tester.  It is simple to use, tests at full power so the tubes are measured under stress, and it displays both test measurements and the specified values to compare the results to.  But, one still needs experience to know what the results mean as to whether or not the tube needs replacement.  The biggest downside to this unit is that it is expensive.  There are kits for testers that experienced tube professionals like.  One expert who owns well north of a dozen testers, including several Amplitrexes said that his favorite is the kit called the e-Tracer out of Taiwan.  Hooked up to a laptop, it will curve trace the tube (the Amplitrex can do that too).

audio-b-dog's avatar
audio-b-dog
42 posts
 

I wouldn't know what once a year is since random tubes blow at different times, and I don't keep track. When a tube blows I replace it. In my ARC gear some tubes doing the same work as others (output stage, for example) blow much before the others. I buy the same brand of tube and do not really hear the difference when I replace one tube in a pair (output, input, etc.) and I'm listening to an old paired with a new. I guess I'm a lazy audiophile or else I'd have a chart and keep track.

brianlucey's avatar
brianlucey
163 posts
 

The adage, if it ain’t broke, don’t fix it ... comes to mind

 

I will often leave my Allnic Audio A-6000 300 BXLS tube amplifiers on 24 seven they are on at least 12 hours a day every day for the last five years, I have an AT-1000 Amplitrex tester, they are still testing in the low 80% range.

the amplifier has bias adjustment metering for each tube, I check it daily and have never noticed any kind of drop, it goes up or down a little based on AC coming out of the wall, but that's about it

 

Bottom line ... every circuit is different, every tube situation is different, if the amp sounds bad or the tube goes bad, you will notice, if you didn't notice, then everything is fine. 

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