Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: audiophileboss on October 14, 2013, 03:19:13 PM

Title: Tube life
Post by: audiophileboss on October 14, 2013, 03:19:13 PM
How long can I expect the stock Bottlehead 6080 tube to last me?
Title: Re: Tube life
Post by: NightFlight on October 14, 2013, 06:03:11 PM
Not speaking on behalf of BH, but standard life expectancy on standard new tubes is minimum 3000hrs. Higher for higher grade tubes, like 5000-10,000hrs. However they're unpredictable and die any time. They are essentially light bulbs... so just think of them that way.
Title: Re: Tube life
Post by: Paul Birkeland on October 14, 2013, 07:34:58 PM
I would add a zero to all of those estimates.

I have had some used 6SN7GTB's in service for five years straight now and they still test as new.
Title: Re: Tube life
Post by: Loquah on October 15, 2013, 01:08:00 AM
I would add a zero to all of those estimates.

I have had some used 6SN7GTB's in service for five years straight now and they still test as new.

Wow! That's a comforting piece of information. Thanks PB
Title: Re: Tube life
Post by: audiophileboss on October 15, 2013, 01:20:33 AM
Thanks guys. If a tube were to die, would it effect my system or damage it in anyway?
Title: Re: Tube life
Post by: Paul Birkeland on October 15, 2013, 04:37:19 AM
Normal tube failure is emission failure, which will not give you any problems.
Title: Re: Tube life
Post by: Paully on October 15, 2013, 04:40:58 AM
I would add a zero to all of those estimates.

I have had some used 6SN7GTB's in service for five years straight now and they still test as new.

Too true, but that is for a 6SN7 which can run for 10-20,000 hours.  I expect the same for my 7N7 in my FP.  But we would expect to get a lot longer from a driver tube.  Output tubes, except for WE 300B, don't last nearly as long.  Or so I am told and have read on the internet so it must be true.  The 45s I am running in my Paramounts are the only output tubes I have left in that long before swapping for something new so this will be my first experience of running some tubes to their expected life.  But I would think 3K hours would be about it.

I don't know how hard a Crack amp runs the 6080.
Title: Re: Tube life
Post by: Paul Birkeland on October 15, 2013, 04:46:16 AM
In the same amp running the 6SN7's, there is a pair of EL34's.  I got roughly 20,000 hours out of those.  The 6080 is running at a reasonable level in the Crack, and it's a very rugged tube.  It wouldn't surprise me to see it go beyond 20,000 hours.

DHT lifetime can indeed be a bit lower than these figures.
Title: Re: Tube life
Post by: Paully on October 15, 2013, 04:59:22 AM
You got 20K hours out of a set of el34 output tubes.  Now that is impressive!  Wow, maybe I will just keep running these puppies until they sound horrible.