Koetsu RoseWood Standard upgrade?

The art of great sound goes beyond the mathematics of sufficient output. If it was that easy, everyone with basic electronic circuitry skills could do it.

To tap into that famous Koetsu magic (and, it is indeed magical) it takes more than a formula.

I have traveled the Koetsu ladder for over 2 decades finally arriving at the Platinum Tigereye. However, to unlock all the nuance that I paid for in reaching the Tigereye level, I recommend the Bob's Devices Sky 30 or the Blue Series 1131. See Art Dudley's Review:

http://www.stereophile.com/content/bobs-devices-cinemag-1131-phono-transformer

I would definitely try the something like the 1131 if you can.
I ran a Jade in to my Monbrison, and didn't feel synergy was good. It had enough gain, but was anemic sounding. Looks like you have a nice system going there, enjoy!

Are you using Koetsu with VPI table/arm?
I tried a few Koetsus with my VPI Classic including
Rosewood and never felt them to be an ideal match.
Koetsu really needs high mass arm like FR
to really show them at their best, I believe.

I am using a Koetsu Azule Platinum on my JMW 12.7 arm and it sounds great with damping fluid. Without the fluid it is lacking in bass response.

I have the Koetsu Platinum Tigereye mounted on a VPI 12.7i arm. The synergy between cartridge & arm is excellent.