I think they have a unique ID for the sound bank so I added it to the PG one:
Copy C:\Program Files (x86)\Songsmith\ARIA\SamplesWAV to
C:\Program Files\PG Music Inc\Band-in-a-Box Sounds

Copy C:\Program Files (x86)\Songsmith\ARIA\Programs > All *.sfz to
C:\Program Files\PG Music Inc\Band-in-a-Box Sounds\Programs
Make backup copy of Band-in-a-Box Sounds.bank.xml
extract below file

https://www.dropbox.com/s/448c43wbm36wd9r/Band-in-a-Box-Sounds.bank.zip?dl=0
Click No Thanks Continue at bottom

You can add it manually if the PG Sound Bank is Updated to the bottom of Band-in-a-Box Sounds.bank.xml just create a backup copy first !:

Code:
    <!-- Songsmith Soundset -->
	    
    <Define name="$A" value="../SamplesWAV"/>
.......
.......
.......
</AriaBank>

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BSF-SS-01.jpg (166.93 KB, 171 downloads)
BSF-SS-02.jpg (130.61 KB, 170 downloads)
BSF-SS-03.jpg (365.85 KB, 170 downloads)