Leaving tube amps on.

Ah, okay @tattooedtrackman, I see the difference. Not 24hrs/day, but all day in anticipation of listening that night.

Still, I would not want to leave the 750’s on without someone in the room they are in. That is generally true of all tube amps, none moreso than those of ARC. And with the short life expectancy of tubes in ARC amps I would not want to put non-listening hours on them. The cost of maintaining ARC amps employing 36 power tubes is a daunting proposition!

I never had problems with my ARC power amps, but my dealer (Brooks Berdan) had shelves full of used ARC power amps, many with scorched circuit boards.

Tubes off when listening session end.  SS on all the time.  SS DACs off when listening sessions are not active.  

You really are best taking your advice from the Manufacturer.

Why!!!

When the worse that can happen, does happen, the Home Insurers' will be gathering their info to decide on Payout from that very place.

Output Valve Red Plating is able to occur in an instance.

The following is a Guidance from an individual much more experienced than myself:

Red plating is always a BAD sign and if you ever see it, turn your amplifier off immediately.

If a valve suffers from this overheating for more than a minute or so you should probably consider it written off.

I suggest being present as much of the time the Valves are in service, as this will enable you to turn the Valves of in an Instance.

Those beautiful glowing tubes are not visible for the ambience they can create only.

They are visible to allow heat to not collect in a case, and enable eyes on the prize, when it comes to witnessing changes in their operation that can cause a fire.

Mollycoddling tube amps is silly to me. Although I maybe shouldn’t make a guitar amp analogy in this hallowed audiophile ground (I use tubes for hifi also, but firmly believe nothing is sacred), I’ve owned tube guitar amps that were turned on and off frequently for decades...worked perfectly...same tubes for years and years in some cases. You take your hifi tube amp on airplanes? Blast it on high gain in a club then toss it in your trunk? For years? I don’t drag any of my hifi gear around as...well...nobody does except to audio shows maybe...still...and the answer is turn the damn tube amp off. Tubes warm up in seconds...

@pindac Thank you for your response. But what is Valve red plating ? I never heard of it.