VAC Signature MK2a pre "phono tube questions"

Dev, I am surprised that you would ask such a question. From all your reports here, you have a wealth of knowledge and experience.

There never is any "right" way of doing things and this includes the tube set that we ultimately run with in any given link in our system. When it comes to tubes to try in a product, a good starting point is the manufacturer's suggested tubes. But very quickly I find tubes from my stash that far exceeds the performance.

When I owned Aesthetix Io and Callisto components, I mixed and matched tube types in each. The Callisto used 4 6922 tubes. I found the ideal match as one pair of Tele 6DJ8 and a pair of Amperex 7308. With the Io, which used 14 12ax7 tubes, I found 10-12 Tele's worked well with the rest as Brimar 12ax7. I have played the same game with ARC products, LS5 and MCP33, that used multiple pairs of Tele, Valvo and Amperex 6922 with great success.

Just try out all your tubes and see if you find a set of 6 that take the VAC to a new performance level.

My point was missed entirely. People new to tubed gear ask such questions. Those with much experience, especially those with a stash of coveted tubes from yesteryear know that the only way to determine if the tubes they have will work .... is to try those tubes themselves.

As for questions concerning why tube manufacturers don't load up their gear with the best tubes is simple.....there is no best tube. And a manufacturer must be able to provide a suitable stock for production and customer support. There's just not enough of any NOS or UOS tube type for a manufacturer to rely on. So their only choice is to install the crappy Sovtek and EH tubes throughout. For those of us who know the benefits of getting these replaced by other tubes, we are on our own. And often we hear the performance of products that far exceeds what the manufacturer ever experienced.

We all try various tubes in our DACs, phono stages, line stages and amps, and with a lot of effort and a little bit of luck, we find a set with a result that can truly be so impressive. A Tele 12ax7 may sound good at one place but very disappointing at another. And the same for an Amperex 6922 or a Mullard EL34.

As many proponents of SS gear would claim, we tube fans are just chasing one set of colorations with another. That's ignorance. No device is perfect. I have no tolerance for tonal coherency problems, but there is always a tradeoff with noise level, resolution, dynamic contrasts, portrayal of space, etc. The key is to experiment enough and deal with as few tradeoffs as possible to achieve the overall system magic. When a tube is discovered in a link that before was our reference at that link, opportunity arises elsewhere. It's simply not possible to do this with SS.

No manufacturer of a tube product will ever be able to provide a tube or tube set to you that will come close to the set that you ultimately discover that you like for yourself.

Sorry Inna, but not a chance. No manufacturer listens to my system in my listening room. Tube selection is not about one component but rather for the entire system. What Vladimir might be able to suggest to "optimize" your LAMM product n the test bench guarantees not at all that this is the ideal r preferred by you in your system.

Rolling tubes for a given music type or even a specific recording would be to much for me as well. I guess this is why many people have multiple phono cartridges with multiple arms or replaceable armwands.