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Audio Research - should I replace the valves?

I have a AR Ref 110 power amp and AR Ref 3 preamp. Both have done about 3,800 hours. They both work but I wonder if should be replacing the valves.

How can you tell if they’ve had it? Does the sound quality deteriorate & what happens if you don’t replace them?

i don’t think they sounds as good as they did but no pops or whistles or any other strange noises etc - just a bit flat sounding. But perhaps this is just my ears?

 

pp

willmarchant
willmarchant OP
11 posts
 

Thanks, I do have a Fluke. I’m going to use KT120 valves in my 110. Is it the same settings? I looked at the manual and it says you should use 120v AC to adjust the bias. Obviously in the UK we have 240v AC or am I being dim?

noromance's avatar
noromance
10,473 posts
 

240v in UK is fine. What they mean is the wall voltage should be at 120/240VAC as the preferred voltage to set bias. This is because the internal amplifier voltage varies if the wall voltage varies. 

curiousjim's avatar
curiousjim
5,959 posts
 

So my preamp used 6922’s and they should last about 5,000 - 10,000 hours, but most power tubes should be replaced every 2000  - 2500 hours. 

senza
80 posts
 

Real NOS tubes last longer than the current Russian or Chinese production. If you want current production, maybe you could buy Sophia Electric KT88 big bottle. They are better sounding than any KT120.

jjss49's avatar
jjss49
6,920 posts
 

should I replace the valves?

yes... as many other experienced hands here have said...

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