[sunseeker888]

Hi, If I were to leave my MKII on 24-7, on the original driver/power tubes, how many hours would you figure they'd last? I realize this isn't an ideal thing to do, but just out of curiosity.... NOS/NIB Mullards or Telefunkens may have a GREATLY higher lifespan and general quality about them, I realize that, but just how shortlived are these valves, when used in the MKII's design?

I feel as if the MKII goes easy on the tubes compared to the LD2++ which ran a LOT hotter. Then again, that amp used 6c19s which are a different tube altogether. Thanks in advance for helping me to clear this up .

 

[sunseeker888]

Bump.... Surely this isn't TOO ridiculous.....

 

[vvanrij]

imo it is

, you'l probably be the first one to try it out too. LD themselve say to let it cool down every 8hours of use.

 

[JimSmiley]

Generally speaking, the tubes should last you around 5000 working hours, depending on your usage and upkeep habits.

 

[Dept_of_Alchemy]

It depends a lot on the quality of the tubes. I would expect the chinese 6J1 to have a much shorter lifespan than say something like the Mullard M8100 which was a long-life mil-spec tube. I doubt very much that the chinese 6J1 will last anywhere close to the 5k hours benchmark, and just as a trivia Mullard-IEC made a very rare and special version of EF95 that claimed to be rated at 10k hours.

 

[Pricklely Peete]

Not a wise practice with (any) tube amps IMHO. SS is a different story though.

 

[vvanrij]

What do the tubes do when their time is up? Explode?

 

[JimSmiley]

Quote:

Originally Posted by vvanrij /img/forum/go_quote.gif What do the tubes do when their time is up? Explode?

They degrade to a "solid state"..LOL

I imagine it's like a light bulb...power switched, but no sound.

 

[atbglenn]

When a tube is near the end of it's life, the sound quality degrades until it becomes distorted and unlistenable. Tubes filaments usually don't burnout, but they do in some cases. BTW, I would never leave a tube amp run 24/7. It will absolutely shorten the life of your amp. Although some hybrid tube amps such as Music Fidelity's X-Can series, are designed to run 24/7 since they have no power switch. They also run extremely cool for a tube amp. (They have no output tubes which is a major source of heat)

 

[vvanrij]

Hmm good to know, but on regular use they should last really really long right? I have 6H30P's and M8100 mullards.

 

[Trapper32]

I'm not sure how long the tubes would last but I'm willing to bet they'll outlast the amp if left burning 24/7.

 

[sunseeker888]

Outlast the amp? Doubt that. I'm not running the LD in excess of 5-6 hours at a time. Thanks for the advice.

 

[atbglenn]

Quote:

Originally Posted by Trapper32 /img/forum/go_quote.gif I'm not sure how long the tubes would last but I'm willing to bet they'll outlast the amp if left burning 24/7.

I have to agree with you. Plus some tube amps run extremely hot such as the Little Dot 2 + and 2 ++ that I had. I'd worry about fire if left on continuously.

 

[ppl]

the Filament inside both Vacuum Tubes and Light Bulbs have a Finite life span due to the fact that there are only so many Electrons to Boil off the cathode Filament. in the case of the Vacuum tube when this starts to happen the performance of the Unit will suffer such as maximum Loudness will diminish and distortion will set in. Manufactures of Tube equipment appear to recommend having the Tubes tested every 6 months to a year. Not only will tubes get weaker with age but some amps require a match set of Output tubes for best performance so matching of the tubes every so often is also required. the Amp may have facilities to perform this task however if absent then another set of match tubes will be required.

As for leaving a Tube Amp or a Light bulb on 24/7? it is advisable not to do so, as stated previously. Tube amps like solid state amps Do require a time to fully warm up and with tube amps i general wait 1 Hour before any critical listening. Solid state amps take a lot Longer IMHO 6 to 8 Hours.

The one thing you don't want to do with any Amp tube or solid state is turn them off and then back on again very often like every half hour as this subjects the component parts inside to undergo thermal stress from heating and cooling. Since Valve Amps operate with a fair amount of Heat the Thermal shock from power on/off cycling will seriously shorten the life of all component parts not just the tubes.

 

[JimSmiley]

Quote:

Originally Posted by ppl /img/forum/go_quote.gif the Filament inside both Vacuum Tubes and Light Bulbs have a Finite life span due to the fact that there are only so many Electrons to Boil off the cathode Filament. in the case of the Vacuum tube when this starts to happen the performance of the Unit will suffer such as maximum Loudness will diminish and distortion will set in. Manufactures of Tube equipment appear to recommend having the Tubes tested every 6 months to a year. Not only will tubes get weaker with age but some amps require a match set of Output tubes for best performance so matching of the tubes every so often is also required. the Amp may have facilities to perform this task however if absent then another set of match tubes will be required. As for leaving a Tube Amp or a Light bulb on 24/7? it is advisable not to do so, as stated previously. Tube amps like solid state amps Do require a time to fully warm up and with tube amps i general wait 1 Hour before any critical listening. Solid state amps take a lot Longer IMHO 6 to 8 Hours. The one thing you don't want to do with any Amp tube or solid state is turn them off and then back on again very often like every half hour as this subjects the component parts inside to undergo thermal stress from heating and cooling. Since Valve Amps operate with a fair amount of Heat the Thermal shock from power on/off cycling will seriously shorten the life of all component parts not just the tubes.

^^^That's good info^^^