"Recently Re-Tubed"

[Old Fart]

Been perusing CL ads and since I love tube stuff, I've been paying attention to tube gear. I swear, at least 50% of the ads for good vintage gear (old Fender Bassmans, old Sunn 2000S's, etc.) state that the tubes in the unit have all just been replaced. That means somebody has taken the high-value, unobtainium old Fender and Amperex and Mullard, etc, tubes out of the unit and probably replaced them with newly manufactured Czech, Chinese or whatever tubes. "Recently Re-Tubed" does not seem like a good selling phrase to me. Just sayin'.......

[will33]

A lot of folks buy into the myth that tubes need to be changed regularly like sparkplugs or something.

[punkinfantry]

the AX7s in my '61 bassman finally crapped out a while back and i replaced them with some JJs. nothing really changed, tone-wise. if anything, it got a bit warmer/brighter!

[JMac4strngr]

Originally Posted by will33

A lot of folks buy into the myth that tubes need to be changed regularly like sparkplugs or something.

Yep, and a lot of folks selling amps think that the "fresh set of Tubes" makes the amp more appealing to a potential buyer. Truth of the matter is if they were planning on selling it when the "retube" was done, They probably went with the least expensive off the shelf tube they could put in there.

AFAIK- The preamp tubes that are in My V4, are probably the ones that were installed at the factory. If so, They are around 40 years old and sound completely awesome. I have no idea of the brand as the printed label on the tubes was worn of when I got the amp, and had the number designation writen on them by a techie with a sharpie marker.

[JimmyM]

If they're stockers, they're likely Sylvanias rebranded Magnavox, or possibly even Ampeg. Very good tubes IMHO.

But definitely, "recently retubed" in a vintage amp makes me think "I'll put cheap Sovteks in there and keep the good ones" OTOH, it wouldn't be a deal breaker for me. Tubes do wear out, even NOS tubes. And Sovteks aren't as bad as some folks make them out to be, at least to my ears.

[coreyfyfe]

Originally Posted by will33

A lot of folks buy into the myth that tubes need to be changed regularly like sparkplugs or something.

It goes both ways. I've had people try to argue for a discount on price since they were "going to have to buy new tubes" when they got the amp without even knowing the history of the tubes in the amp.

[skychief]

Originally Posted by will33

A lot of folks buy into the myth that tubes need to be changed regularly like sparkplugs or something.

well, like sparkplugs, all tubes do have a life span ...gauged in hours of operation and level of operation (biasing, loading, environment, temp, etc) , rather than mileage.

As most folks dont log the amount of hours their tube amp has been operating, its a guessing game as to when the tubes start becoming weak, then ultimately fail. Not a happy event at a gig or important session.

So when a seller sells an amp with a new set of tubes, it implies at least 200 hours of reliable service.

I will concede, tho, that the replacement tubes are probably not as good quality as the ones they replaced.

[fretno]

I never expect to find great NOS tubes when I buy a amp , I just pop them in when I get it .

[JMac4strngr]

Originally Posted by JimmyM

If they're stockers, they're likely Sylvanias rebranded Magnavox, or possibly even Ampeg. Very good tubes IMHO.

But definitely, "recently retubed" in a vintage amp makes me think "I'll put cheap Sovteks in there and keep the good ones" OTOH, it wouldn't be a deal breaker for me. Tubes do wear out, even NOS tubes. And Sovteks aren't as bad as some folks make them out to be, at least to my ears.

Thanks, JimmyM
Yep, I'd think they're probably the Sylvania's as it's a Magnavox era amp. I did try a set of EH's(Sovtek) in it very briefly, and It didn't sound quite as pretty(kinda fizzy). I guess, I might should be on the lookout for some NOS tubes just in case.....

Sorry for the derail guys..... Back to topic...

[JimmyM]

Originally Posted by skychief

well, like sparkplugs, all tubes do have a life span ...gauged in hours of operation and level of operation (biasing, loading, environment, temp, etc) , rather than mileage.

As most folks dont log the amount of hours their tube amp has been operating, its a guessing game as to when the tubes start becoming weak, then ultimately fail. Not a happy event at a gig or important session.

So when a seller sells an amp with a new set of tubes, it implies at least 200 hours of reliable service.

I will concede, tho, that the replacement tubes are probably not as good quality as the ones they replaced.

Exactly. I'd rather take my chances with the old ones as long as the amp sounds good.

[msquared]

Originally Posted by fretno

I never expect to find great NOS tubes when I buy a amp , I just pop them in when I get it .

This.

To me, retubing isn't a deal killer. Quite the opposite. To me it's like drum heads on a drum kit or new tires on a used car. I'm not really going to use what it came with unless I don't have that particular tube sitting around or unless it really sucks. If I care *that* much about the difference between crappy and unused NOS tubes, I'm going to get them myself and go with what I want rather than what flavor of NOS someone else thought was great (and subsequently thrashed).

[miholc]

Originally Posted by skychief

So when a seller sells an amp with a new set of tubes, it implies at least 200 hours of reliable service.

At price 260€ for matched sextet I seriously hope for that number being bigger.

[Mr. Foxen]

I pretty much regard it like 'new strings' on a bass. Either way they are coming off for a setup and service, and I'll put my favoured flavour on. If someone wants to haggle the price based on it, I'll say send it without any in. Safer that way for shipping, I prefer sending out amps unvalved. I think modern/recent (as I think the latest are better) valve should be regarded like lightbulbs more than spark plugs, some go fast, and some go faster if you switch it on an off loads of times.

[bertbass666]

In the 60s & 70s it was usual for output valves, tubes, to last about a year before needing replacing. Preamp valves used to last a lot longer although they did tend to go microphonic after a while. I once owned a Simms Watts AP100 and you could hear the volume and tone go as the valves got older.

[Mr. Foxen]

Funny, I have amps from the 60s and 70s, well used, still running the original power valves. Think Simms Watts did push hefty voltages compared to some though, and the still going valves are the top quality ones, maybe the forgotten cheapies didn't hold up.

[delta7fred]

I have a 100w tube head that I gigged, rehearsed and practiced with from 1968 until 1998 and in that time have changed one ECC81 and one EL34 (but it may have been 2). I worked in an an electronics lab (that had a valve tester) and checked the tubes regularly, I only changed them when they were out of spec.

200 hours for a tube, I probably clocked that within the first couple of months. When I was young free and single if I was not at work, asleep or eating then I was usually playing bass.

[Bassmec]

Originally Posted by bertbass666

In the 60s & 70s it was usual for output valves, tubes, to last about a year before needing replacing. Preamp valves used to last a lot longer although they did tend to go microphonic after a while. I once owned a Simms Watts AP100 and you could hear the volume and tone go as the valves got older.

I have a Simms Watts AP 200 super and 2 of the 4 gec KT88's date codes are the 1971 originals, I changed out all 4 for a set of winged C cryo a couple of years back when I installed it in the rehearsal facility here. then 2 of them started red plating within the year, so I put the best matched old pair back in.
The GEC's are still testing emissions good, still biasing the same-ish quiescent current as a couple of year old pair of winged C's.
Good tubes last very well, bad tubes are just bad tubes.
Bias can drift and just like with transistor amps it needs rechecking every now and then.