Question on Tube Swapping and Biasing

As is usual with Luxman this is all they have to say about it in the manual "When repairs and adjustments are needed, please consult 
with the dealer where you bought the unit." since they'd really rather have you not messing with it.

FYI, bias is a moving target. Knock your brains out trying to get it right on the money then blink. In theory a matched quad is all you all you need to do but the primary caution is not having a single tube or tubes drawing significantly more current than any of the others. Other than that, the bias is likely to be all over the place at anyone given instant and is nothing anyone with a tube amp should ever obsess over.

Your JJs are probably still just fine and unless you have any particular indication that things are not as they should be, you should leave them alone.

Thanks for your suggestions. Obviously there's a variety of opinions on how to approach this! 

From a dealer / manufacturer point of view, they obviously want to err on the side of caution and recommend that you use a professional audio repair shop to carefully check the bias on a regular basis. So I suppose that's one end of the spectrum. 

I was told by the Luxman guy that, since I stupidly removed the original JJ tubes without noting which one went where, if I out them back in I'd have to bias the JJ tubes all over again. The Gold Lion are indeed a matched set. So technically I need to bias the tubes. 

Then again, I've had the amp 5 years without worrying about bias at all. I'm sure it's changed over time. 

Have to say, I'm more confused than before!

Sounds too complicated for me.  Think I'll stay with a SS upgrade.

VTL bias meter

This is a great way to safely check bias   

Getting ideal performance, prolonged life, .... may be nice, but ’not ideal’ is still ok, unless they glow too bright, seem too hot.

Not even knowing bias existed, I listened to tubes for many years, this thing had more tubes than you could shake a stick at, I inherited it in 1973, age 25

https://www.audiogon.com/systems/11420

Fisher 80AZ Mono blocks. Never biased them for 50 years! I had them worked on, resistors replaced, perhaps they were biased by others and I never knew it.

I Have 3 Fisher 500C Tube Receivers, had one Fisher 800C, used them for years,

have my own tube tester, and a large collection of new and used tubes. 

replaced old weak tubes, ones with shorts, ... with good used or new

Never a problem, nothing ever glowed too much or burned obviously hot

I bought a Cayin A88T tube amp on eBay, designed for KT88’s, came with 6550s. Did the seller re-bias for the 6550’s when he put them in?

I read about bias, it has internal adjusters, no meters, so I gave it to Steve Leung at VAS (former Cayin USA Rep) to re-bias for the KT88’s.

I hear no difference, they never were suspicious, and, who knows, perhaps the original factory bias was better for my KT88’s than the 6550’s it came with.

Don’t let too much knowledge keep you from enjoying your Luxman.

I think I wasted both time and money having my Cayin biased.