1. Home
  2. amps-preamps
  3. 195077-47456

I changed a Tube and…

I liked it!
 Have a Rogue Audio Cronos mag lll bought it years ago as original Cronos Mag  sent it in last year for the upgrade to lll .  Never changed any of the original tubes .

The amp was lightly used due to my changing amps like regularly. Decided to stick with Cronos and and have really enjoyed it . 
Playing vinyl for the majority of time and seem satisfied with Triode mode .  Amp runs perfectly no noise at all but thought about all the threads regarding tube rolling  especially the center 12au7 . 
pulled out the stock JJ and found a Genalex  Gold Lion ECC82/B749 (12au7)  bought them 7-8 years ago .  
Put the GL into center position and was thinking “am I going to really hear a difference “???   Figured I listen to a few LPs and maybe I’d notice something different good or bad Maybe ? after all it’s just one tiny tube !

Well I was blown away !, 30 seconds in listening to “two of a mind “ Desmond /Muliligan  things just got a whole lot more musical 🎶. Hard to describe everything seemed improved , midrange was wow ! Soundstage was better , etc .

Went to another familiar favorite Grant Green “ Idle Moments “   Oh yes the magic is here too 

Is this even possible or am I under a placebo delusion  lol 

Now I’m really wondering what about the other 2  12au7’s  and even the 2 -12ax7’s

what else am I missing ? 

 

 

 

mfm22
chickenoregg
39 posts
 

@thecarpathian 

My understanding is that different shaped getters were used to guide/control where the barium patches ended up. I've always though of them like a wine glass that's designed for specific type of wine to maximize how that particular wine hits your nose and tongue; e.g.. like how a Bordeaux glass differs from a Burgundy glass.

They are also indicative of a date of manufacture. But after the vacuum is created during the production process, they really serve no purpose. I have tubes with huge foil getters that broke off at the post were it meets the mica and it rattles around in there like a maraca. They work fine, like more prone to issues down the road, but a tube with a broken getter is far from a horse with a broken leg.

chickenoregg
39 posts
 

@larryi 

But this starts with the false, outdated presumption that each specific model of whatever piece of gear must have the same tube as every other piece of gear with the same model number. In the age of co-creation where you get to pick the kind of wood you want your amp built with there is no reason you cannot specify also an NOS tube that is to your taste. The manufacturers that embrace this instead of fighting it I think will be better for it.

chickenoregg
39 posts
 

@noromance 

Let's talk more about tubes we like. I expect we have a lot of overlap.

I also like the Siemens 3-Mica E83CC short plates. I had a quad or two of some long plates that were nice but didn't do much for me.

I very much like the Siemens mC3 and mC5. The mC6 is a bit lush for me. And the mC1 can feel a bit too airy, but has moments of brilliance. 

My two favorite 12AX7 are hands down the Valvo mCn/mCp tubes and the second one isn't even a 12AX7 - it's the GEC A2900.

I don't run 12AX7 much these days, I favor octal tubes with adapters for the most part. The GEC/Osram/Marconi B36 is one of the best values in audio tubes, period.

I just sold my entire system and am rebuilding it around a VAC 200iq that shall soon be two VAC 200iq's. I am currently experiencing the unique torture that is picking new speakers, preamp, and DAC.

The only thing i can tell anybody about "new" Telefunken tubes is that there is no such thing, unless you are referring to Ei tubes, which is 2/3 of a thing.

More to discover