I prefer the 12AT7s in my Zstage over 12AU7, particularly I like two early 60s Brinmar and a 50's Siemens with a square getter. The 6N1P, 6922, 6DJ8 type tubes are way too heavy handed for me in the Zstage. It will be interesting to see how you like the 12AT7...I expect that to be a big change.

Fun on the horizon!

Thanks for sharing those thoughts, Syd.  

That sounds about 50 hrs of settlement, consistent with what has been indicated in this forum as the expected basic break-in horizon.

It definitely must help to have documented reference on your tube findings.  After all, I imagine rolling several in sequence (with the respective burning periods) ought to create some confusion due to their interactions (aside from worn label printings).

I'll take advantage of your suggestions, thanks.

Lon,

That is one of my concerns.  I would not have decided to get them due to the highish gain reasons you indicate (also as per Steve's comments).  But I had this positive feedback, and the tubes were readily available, so I felt like giving them a try.

Sometimes the brand and build quality make major differences, as I've read, so a first-hand relevant positive testimony was hard to ignore.

I wish Steve would shed some light on the reasons behind the 6N1P-Ev in the Mini driver's seat (pun intended!).

Quote:


I think you will be fine FB. When you listen to the Brinmars you will know.

I originally thought you would have been using 12AU7s, but since you are using 6N1P, and as you say, the individual tube makes a big difference in terms of how the sound is presented and feels....but generally my guess is that the Brinmar 12AT7 will open things up a bit in the low mids and tighten the bass...perhaps meeting your previous idea of where you wanted your sound to go.

great  ;D

Hey Les,

Your proposed method ensures the fastest break-in period as all would be cooking at the same time.  Since the Brimars take the longest, by the time they are ready all will.  Makes sense.

I thought I would go one at a time, starting with the rectifiers while still able to listen to some real music, but you're right.  It's the fastest path to start the experiment.  The first 24 hrs will be just iddle filament heating, and then on with 'offensive-sounding' music playing.

Can I just leave the thing going on 24/7 or should I apply the 5 hrs on and 5 hrs off rule?  It would be a lot faster just leaving it on 'repeat' or something (at low volumes), if it won't damage anything.   What's the ideal volume setting in this period?

Thanks for the suggestion.

FireBlade,

To me Lord Soth's 24 hour run without music makes some sense on a new tube (though N in NOS means new, apparently, many tubes called NOS may not be brand new) ... running hot for this period might cause the metals and glass to work into their proper alignments and relationships.

Then, it seems most say that music is necessary to burn them in...leaving them on without music, mainly just putting life on them.

I can't quite imagine the 5 on 5 off thing being as beneficial for tubes as caps, but seems flexing the materials, expanding and contracting, and vibrating into their new role...on and off could make sense in burn in. I really can't say. But Les' idea of having the amp on in the day and off at night would do this if it is beneficial.

In my experience, Rectifiers and VRs tend to burn in faster and not have as bad a nature before burn in as inputs and power tubes can. And some inputs and even power tubes are not even that bad after 5-10 hours. Some are worse, as Les says your Brimars are. In my experience warmer tubes tend to be harder to get to open up.

I find Power tubes the worst, taking anywhere from 90-300 hours to really come in, again, the warmer tubes taking longer to show their detail qualities in a smooth and complete way, generally working from the top down, the bass resolution coming last. But these are EL34s, and I don't know how this relates to the MT power tubes.

The reason I talk about all this is that it might help with your tube play strategy. One point being, some tube types, and also some individual tubes, especially brighter ones, can sound tolerably good pretty fast, finally getting refined with time.

And the other point...with the right tube set combination/synergy, you can get really OK sound with even two or three newish tube pairs.

You will feel it out, but burnin will likely not be bad, and even quite good if you play your combinations well.