My really dumb tube mistake(s)


8 years ago, I bought a sweet sounding Line Magnetic amp for my office system which a few years ago died and had to go to the repair shop. $500 later it was back working, but then recently I noticed the sound was getting thin, I couldn’t bias the tubes and thought something else was wrong with it, arghh.

Then I noticed one newer tube was able to be biased and decided to replace all 4 KT-88 power tubes.
Presto, the amp sounded great again!

Like the boiled frog, the sound degradation had been so gradual my brain had gradually adjusted. But the new tubes brought it back to life.

So, then I thought, wow, maybe I should try the same thing in my primary system with my Primaluna monoblocks, switch out the Primaluna tubes for some new Gold Lions. Again - wow! What a difference. Like I bought new amps, much richer and fuller sounding.

Tubes wear out, even if they don’t blow out.
Yes, duh, it’s a good idea to replace them every 4 years or so and not wait eight.
cdc2

Showing 4 responses by oldhvymec

Roooooooll, another one, just like the other one.

Lets stick to the subject, roll another tube, just like the other one..:-)

Regards
pindac 

good to meet you.. that was quit a bit of information..

Did you say "if you roll tubes, you can get good result, but you can have bad result too". I agree.. :-)

Regards
I don’t see it as a mistake, I see it as getting every last mile out of that tank of fuel... Well done..

Regards..
You know douglas, one thing that I found out. If a valve can make it the first 72 hours, they will usually last until they just run out of gas, (99.9% of the time). That last 10-15% can get a little wiggy, though. :-)

Sounding GREAT out of the box is always nice.. The OLD RCAs and Tellies always did it for me.. VERY consistent from day one.. PSVANE and a few of the Boutique valves can take 100+ hours to sound right..

Regards