Disklavier

Hello!
Im going to try kassey22000 suggestion with my mpx1: to use both controller the "old" one as master and the dkc850 as slave both connected through midi cables.

Since Im using quite much the midi connection with my Imac (dkc850 midi out->midi interface->usb Imac) I find that with this new way to connect both units Im loosing the possibility to connect them with my Imac through midi.

Is there a work around ? I thought about the "TO HOST" port on the old unit but it seems that to work it needs to be switched on "midi" or on "mac' so selecting "mac" would cancel the midi connections with the dkc850.

I also thought about a midi merger : Imac midi out + dkc850 midi out-> old unit midi in AND reverse  old unit midi out-> Imac midi in + dkc850 midi in... But having not such merger I wonder if this would work...

Any other ways I could try  to achieve midi connection  fro/to Imac to the combined set up dxc850-Old control unit ?

Actually, its for the same reasons as kassey22000, even on my mpx1 the dkc850 lacks what the older controller had:
-Cannot record multitrack midi sequences
-Cannot record incoming midi data
-Cannot output midi data other than live piano playing (no playing of stored midi files)
-Soundcard worst -Audio output soft

After nearly 9 months of using the dkc850 I must say that I am considerably disappointed in the machine. It seems that Yamaha made a unit which is quite limited and for no apparent reasons. What it brings is more storage posibilities,  network connection and some other improvements with video sync etc. 

I am a musician and I compose also quite a lot, so for me the downgrade of the unit concerning the midi functions are very important. Indeed what can you do if you cannot record properly and edti the material outside in a sequencer for exemple? Also the midi out blockage forbids the synchronisation with other material through midi. I find that a major flaw. 

Finally that infamous soundcard which they have chosen to bring on board is just scandalous, and specially for a firm like Yamaha who produces synths for nearly 30 years. Its sounds are really not what one would expect from such company at the time we actually live in. So again if there is no midi out you are stuck with those sounds...!

So adding the old controller (in my case dkc500R) can help . I have already found a way to send midi out (from both controller to my IMac and vice versa), I can now record outside the mpx1, send back the result AND record the incoming midi in. In this configuration the only loss is the dislavier radio.

Fortunately my old controller still works, because the day it stops working this set up wont be possible anymore... which brings me with my main wish for the dkc850: that Yamaha  brings changes in the unit through software upgrade and as retrofit to cure the unit of those missing essantials. I dont understand their choices, the pianos are made with a musical mind and heart behind them but that unit seeme to have lost its soul "en route"! Unless it was aimed only to hotels and restaurants, but even there the sound quality is so not up to the task, nowadays with the strings that sounds like that is just a shame... considering the price !

Sorry for the outburst but I am surely not the only one feeling like this. To come back to the topic, I m sure there are other ways to counter the limitations , if you have ideas please share them here .