Gold Lion KT77 tubes for Primaluna Amp - a few questions


I have a Primaluna Dialog Premium HP amp (stereo mode), and am currently running the stock el34s.  With 4 per channel, the re-tubing and tube rolling discussions can get expensive, so I have been treading lightly. Having read numerous threads (lots of great discussions and comments - thanks to everyone who has contributed) I have decided to give the golden lion KT77 tubes a go.  I have a few questions.

1- in looking around, I see there a multiple sources of the tubes.  From multiple eBay sources (some which appear to specialize in tubes and others that do not, some are “genelex authorized dealers”) to the well known Upscale Audio.  The pictures of the tubes all appear to be similar.  Am I correct in assuming they are all the same genelex “made in Russia” tubes?

2- one of the things that appears to differentiate the different suppliers is how they match them.  Is all matching the same, as long as they are “close enough”?  I see factory matched, hand matched, transconductance, plate current, 5%, 10%.  Lots of stuff here.  ESPECIALLY for the self biasing Primaluna amp, how critical is the matching method?

3- one last question about dealers.  I am in the Chicagoland area and I recall somewhere someone saying or posting that they buy all their tubes from a local company, that was very good and knowledgeable. Does anyone know who this dealer is? All things being equal, supporting the local economy (and being able to talk to another audiophile across the counter) is a good thing.

finally, just so we don’t go down a different rabbit hole, I did replace the center two 12au7s with mullard NOS 4003 from Upscale Audio.  One of the best things I have done to my system. Wow.  I plan on changing the other four, too.

THANKS 

Bill
meiatflask
RAM tubes. CORRECTLY tested and matched tubes by the most knowledgeable tube expert/authority alive, Roger Modjeski of Music Reference. He has supplied tubes to other amp designer/makers such as Mike Sanders of Quicksilver and Ralph Karsten of Atma-Sphere, and approves of and sells the Gold Lion tubes.
So it would make sense (in my pea-sized brain) to purchase the KT-77 tubes from Kevin @ Upscale Audio. You already have one positive purchase experience with him. Although he’s not the lowest cost provider, you’ll have the peace of mind knowing that the tubes have been thoroughly tested and burned in.

 

For reference I own a PrimaLuna Dialogue 4 and run the same (Upscale Audio purchased) Gold Lion KT-77 tubes in it. I’ve made many tube purchases from Kevin over the years and never had a single negative purchase experience or received anything less than stellar advice/service. 


I've been using the PL HP for a few years. Great amp with whatever tubes used.

Matching isn't a concern with the auto bias. The GL KT77's retain the great mids, and you may notice a little more extension  on both on both ends. YMMV. 

Changing the 4 other preamp tubes aren't as noticeable like the 2 gain tubes.


My KT77s came from a reputable Ebay dealer, and were supposedly "factory matched." They're the best sounding tube I've tried in my SE power amp (only 1 single ended power tube per side), and that list includes KT88s from Sovtek and Gold Lion, Tung Sol 6550s, KT150s, and KT120s...all of the above sounded great (JJ KT77s were also tried and sounded not so great), but the GL 77s are better by a surprisingly large margin. In my amp they might (not sure) lop off 2 watts of the supposed 12wpc I get from other tubes (Dennis Had Firebottle high output amp), but it's not noticeable.