Sharing registrations between different lines of keyboards can be problematic, depends where certain feature exclusive saves were created and saved to that registration. Obviously in your case certain Yamaha registrations can be somewhat compatible with another Yamaha arranger.
I always own two arranger keyboards at a time. The second one is always ready as a backup. Lot more convenient keeping my home studio Tyros wired and setup, and my gigging Tyros ready to go in it's soft case. Any registration, style, multipad, midi files, or audio file changes or edits are safed to my USB stick and transferred to my gigging board.
Everything is kept in duplicate, down to the wires, mics, stands, and midi bass pedals. I keep a set of 10", 15", 18"subs lightweight powered JBL EON speaker system. I take only the combination of speakers I need for the venue size.
Worked out well in the past having two PSR arrangers and traded one for a Tyros 3, and then when the Tyros 4 came out, trading last remaining PSR for the Tyros 4. Sharing registrations between the Tyros 4 and the Tyros 3 wasn't that difficult and worked out well for years. Also any older style was easily upgraded to the newer keyboard voices and drum kits.
When I traded my Tyros 3 for my first Tyros 5, I had a much more difficult time sharing registrations between my Tyros 5 and Tyros 4, because I benefited so much from the newer Tyros 5 features and addition Mega, SA, SA2 voices. I use Organ World, Ensemble, and the newer DSPs all the time that I hated having to gig at times with my Studio Tyros 5 for the odd special occasion, having to strip down my studio setup each time the need came that I used the Tyros 5.
Ultimately my solution was to sell my Tyros 4 and get a second Tyros 5. Found a great deal on a demo Tyros 5 with full Yamaha warrantee. Greatly satisfied using the Tyros 5 exclusively and totally free to create and share exact registrations and expansion data between the two boards and benefit from all the TOTL arranger features and great keybed with aftertouch control.
Sorry, I actually ranted on longer than the original post. I can see the attractiveness of the lighter and more compact PSR S970. I can see more similarities between a Tyros 4 and a S970, then a S970 and a Tyros 5. I could see that working fairly well keeping both the Tyros 4 and a S970. Just a little work reworking some styles and voices and making shared registrations or rework any new registration to suit the second board.
Of course everyone's needs and situation is different, but certainly easier sticking with one arranger brand when trying to share similar setups and registration for gigs and when the need arises to upgrade to the newest board. Never had a breakdown with a Yamaha product, but keeping two boards also shares the wear and tear and can potentially keep the boards more reliable and in better shape for trade in value or selling to another person. I even keep the screen protective film on my Tyros displays.
Marcus
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