Question For Those In The Know About Audio Research Power Amps

@minorl
@fsonicsmith

Great posts/info, thanks.

I wrote a long update on the situation but the whole post was taken down by admin.
I’d forgotten we’re all children here and need to be protected from such profanity.
Does anyone know how to get a post reinstated so I can update on what’s transpired between dealer/ARC/myself?

Thanks everyone I’ve learned a lot from this thread.

Rooze

I talked to my AR dealer this morning. ARC is evidently charging $275 for the KT150's. That is EACH. So in case you are not good at math, with shipping and tax, you are looking at close to $2400 to re-tube a Ref 150SE like mine. It tempts me to seek a trade for an ARC Ref 75SE. They are not necessarily scalping-they need to buy huge batches of tubes to find suitable ones, expend the time to perform the testing, and can't simply return the rejects for a refund. But I stick with what I said previously, ARC bet the ranch on the 150 tube and the consumer is left to pay for that choice. The situation is slightly ameliorated by the toughness of the good KT150's that will go 3000 hours, but only slightly, 
ARC has never been a value-driven product but now under McIntosh they seem to be a lifestyle-based product-for show and bragging rights. One could argue that AR had no means of predicting that New Sensor would have such QC problems with the 150 tube but AR has done nothing to guide their buyers on the topic of alternative tubes. I intend to try Genalex Gold Lion KT88's and see what happens/hope for the best. 

Yep, that is the case for KT150 tubes.  I imagine that one could use KT88, KT90, KT120 tubes instead if you desire and they fit the sockets.  You would have to know the new bias points.  But, a simple call to Audio Research would confirm this. 

Audio Research equipment was modified to accept KT150 tubes, this meant upgraded transformers to hand to power handling/draw capabilities of the KT150 tubes.  If they can handle KT150 tubes, they can definitely handle tubes that came before with lower draw characteristics.

But as I mentioned earlier, since most manufacturers can't possibly know what new technology or tubes will be produced in the far future, it is impossible to design for them that far in advance.  You design for what you know now.

If you can find an alternate tube supplier that will supply matched tubes within Audio Research's specifications for that amp, for a lower price, well,, go for it. 

I can tube roll to my hearts content with my REF 250 amps and my REF6 pre-amp and REF 2SE phono stage, up to the current level of tubes that they can handle.  'For my REF250 amps, I just can't go above KT120 level.  not big deal.

its like with supercars or Mercedes or high end cars.  The maintenance costs is very high. People find themselves in hot water when they purchase something without investigating the maintenance costs first. 

That is a serious shock when the bill comes.  not a big deal with pre-amps or tubed phono stages, but for large powerful tubed power amps,  This could be a down payment for a new car replacing the tubes.  

thinks the REF 150 tube replacement is bad?  or my REF 250?  Look into tube replacement for a REF 610 or 750 amp.  or other manufacturers that make large tubed power amps.  Tube replacement costs is no joke.

not for the faint of heart.

enjoy

Re: tube replacement costs. Apologies for the digression.

when I bought a Mesa Baron c. 1996, they offered half-off the cost of new, matched tubes (I understand their tube-matching is second to none) to original owners. Not a trivial expense, with 12 power tubes and 4 12ax7a’s.  They still honor that promise, 24 years later, long after withdrawing from the audiophile market.  Now THAT is customer service!  AR seems to take the opposite approach.
I enjoyed an AR linestage and and still have an upgraded ph3SE phono stage, but their power amps were always said to be difficult to bias and burn through tubes quickly.  I just couldn’t take it.