TU-8900 upgrade

The P3ESR is much more than adequate to hear ANY improvements in the upstream components.  It is surprising how well all of these speakers based on the BBC LS3/5A speakers sound and how much they appreciate good upstream components.  I've heard, and liked, a number of Elekit amps.  However, if you do push the P3ESR hard with such low powered amplification, you might run out of steam (the first sign would be compression -- the music stops getting louder and sounds more "blah"-- and the sound becoming more muddy.  I am someone who believes most people grossly overestimate the amount of power they "need," but these speaker do need more power than most speakers; they are not as easy for tube amps to drive as some other BBC LS3/5A variants that have a 15 ohm impedance.

I don't know about the upgrade options.  You should talk to Victor Kong, the North American importer.  He is usually quite frank in his recommendations.  

No idea about the transformer upgrade, but past that the cheapest/easiest thing to do would be to add a linear power supply (LHY, SBooster, Teddy Pardo) to the Node that will yield a nice performance bump.  I assume you’re using the DAC in the Node, so that’d be another obvious area for a significant upgrade.  If you were to add the LPS and get a good DAC I think you’d be at a much higher level.  If you really wanna up your game pair one of the above power supplies with an Innuos Pulse Mini and a good DAC — not cheap but would be another level of improvement and give you a USB output.  And yes, I think your P3ESRs would reward you for feeding them a much better signal.  Just some thoughts FWIW, and best of luck. 

I did a test of the P3ESRs, I moved them over to my main system and was very surprised at how the sound from approx. $2k speakers compared with that from the $37,.5k Rockports!  The lowest base was not there and they were not quite as transparent, but I was amazed especially at the midrange. I played my "emotion test piece", the third movement of the Op. 132 and was transfixed just as I am with the large speakers.

I m not sure why I had not done this earlier (duh!)

I am now undertaking a rework of the 2nd system.

I have ordered the Lundahl kit from the UK, let's hope it gets through import without crazy tariffs.  Also a pair of Jupiter Copper/Beeswax caps.

I am going to order the Eversolo DMP A8, it has excellent reviews, there are positive comments on this forum, and it is small enough to fit in the bookcase that acts a a stand for the 2nd system.