Kembles are now made in the Jakarta, Indonesia factory - by Yamaha. The UK-built Kembles from cirxa 1995-2009 were made in Milton Keynes, UK at the Kemble factory. But... Yamaha purchased controlling share of the Kemble factory and had their European-market pianos made there. The factory was vastly upgraded to Yamaha's legendary precision standards. I toured the factory in 2003 and it was very 'Japanesque'... All the components in a Yamaha or Kemble piano made in that factory during this period are from Yamaha - with the exception of the soundboards which were 'Strunz' Bavarian spruce. The only Kemble element of the piano is the cabinet styling plus additional voicing in the factory prior to release to the trade to ensure the tone is mellow, where Yamaha branded models would leave brighter... but this is technician time, not design/material/build difference. We stopped stocking Kemble pianos in 2004 as we found it confusing alongside Yamaha... where aside from the cabinet styling, there is no fundamental difference - at all.
The move to Jakarta for European series Yamahas and Kemble branded pianos, was needed as the factory was not making enough profit and the Jakarta factory had proved itself in
the Yamaha B1, B2 and B3 uprights,
the Yamaha GB1K baby grand production - including silent and Disklavier (DGB1K) variants. Dare I say it, if there is any difference, Jakarta has a more consistent output and as of yet, zero cabinet defects. The factory voicing is definitely superior - not so much the amount brilliance reduction, but the method used and the uniformity. The cabinet finishing is excellent.
The Conservatoire is the equivalent to the UK-built Yamaha PX124NT/PX124G (no longer in production). Hype aside - this is a K121 in a bigger cabinet. The keyboard is higher, because the base of the piano is raised. Open the bottom door and you will see a gap of approx. 3cm between the floor of the piano case and the frame/soundboard. If you prefer the appearance, then there is a difference... the tone is only very slightly fuller as a result of thicker side panels (approx. 20% thicker than most other pianos). There is no other difference. The K121 is 121cm and the Conservatoire is 124cm.
Should you be considering a Yamaha? Yes. The P121 is also made in the Jakarta factory and too has the Strunz Bavarian spruce soundboard. These pianos collectively are based on
the Yamaha U1. The frame, soundboard profile, bridge, soundboard ribs, backposts, action, keyboard, hammers and dampers are the same. Yes, it is subjective, but only when there are actual differences that someone can prefer... in this case - i find the product range highly confusing the customer and have to stress that if all 4 pianos in question were from the same factory, lined up against the same wall with no acoustic variance in the positioning in the room and 1 sole technician prepared them precisely uniformly, you would choose the one you prefered the look of and price of. The Conservatoire should have a slightly fuller bass/tenor owing solely to the cabinet thickness but also, there will be a difference in keyboard height to factor in (more/less comfortable). All are very good instruments.