Hi Justin,
The sound qualities of all the units are very close to each other. Any of the units should noticeable improvement.
From technical specs the quality pretty much from the top goes UFX, Babyface, ADI-2, FF800, FF400FF UC. The FF400 and FF UC are the same converters
The Babyface does not work as a standalone device like the FF400, 800, UC and UFX can.
So it will be the Fireface's units or the ADI-2.
The ADI-2 is just a high quality stereo AD/DA so will have just the function of improving your stereo output.
The Fireface series can all be setup as standalone multi-channel AD/DA you just need to hook up to a computer the one time to setup the routing.
If your LS9 has the ADAT card or can use the MY 16 ADAT card then the Fireface series will be even more useful. In standalone Mode on the Fireface 400/UC you will get up to 8 channels of analog I/O expansion for the LS9. The Fireface 800 and UFX both have 16 channels of ADAT so if your LS9 can use the MY16-AT expansion card then you have even more analog I/O available. With the FF800 you will get 10 analog I/O and on the UFX 12 analog I/O in standalone mode.
The Fireface series when hooked to a computer also have the added benefit to record and playback multiple channels so this can add to the services you offer now that you will be able to record performances if needed and have a multi-channel sound playback system.
The UFX is the ultimate choice of the bunch because it is the closest to a completely standalone unit. It's front panel can control all the settings of the unit with no computer attached. It also has a built in recording ability. You can just plug in a USB driver and record up to 30 channels at a time without a computer.
The Mic-Pre amps on all the units are very good. The UFX technically has the best Mic-Pres of the Firerface series. It along with the FF800 have 4 which would make them more usable in this setup.
Thanks Chris
Chris Ludwig
North East USA Sales | Synthax/RME
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