Kemper Stage SPDIF out to UA Apollo Twin X Optical in

  • Converters to/from coaxial SPDIF to optical TOSLINK are certainly available. The Stage has the advantage over the Toaster and Rack in that it can be either clock master or slave. I would run it in slave mode to avoid your interface having to re-clock upon connection of the Kemper.

    Something to look out for would be the latency of the converter (see if you can find published specs for one). It’s unlikely to be significant but worth confirming.

    The Apollo twin has a nice feature that the optical input can be either SPDIF or ADAT format, so you’re good on that front.

    The Kemper analogue outputs and Apollo inputs are both class-leading, so you’d miss out on all that groovy preamp modelling in offer, but if you’re re-amping etc. Back from your DAW it makes a lot of sense.

  • There are other reasons to connect the Twin and the Kemper.

    1. Since the S/PDIF I/O on the Kempers cannot be used to access the effects loop(s), connect the Twin in the second loop of the Stage via analog. Now you can use the time based effects on the UA platform with the Kemper’s profile.

    2. Use a preamp profile (no power amp or speaker). Connect the Stage to the Twin via either analog or S/PDIF. Load a UA amp sim that can turn off the preamp section. Use it as the power amp and speaker sections.

    3. Connect the Twin and Kemper via S/PDIF. You can now use the Kemper effects on a track in the Console or Luna without a profile loaded.

  • Thank you for the replies.

    For my usage as a quarantined guitar teacher working via ZOOM I am just trying to preserve the stereo Kemper sounds in while leaving the Apollo mic pre's open.

    I was originally using a cheap behringer mixer in between the Kemper and Apollo to get Kemper stereo out, a vocal mic (also picking up acoustic guitar) and my iPad running spotify and the Amazing Slow Downer app for transcribing/ content video production. The extra gain stage was making things a little complicated and changing the Kemper sound a bit for the worse.

    Edward, There are lots of spdif to optical converters out there but I was looking for one that has been found to function optimally in this situation to save time. I had a Kemper support answer recommending that this may be a frustrating journey as no add on unit can be verified by them so I gave up on it for now. I took the suggestion to go mono master out to Apollo for now. This leaves the second pre open for my vocal mic and now I just have to free up a usb port in my iMac for my iPad to get the Slow Downer audio in.

    I would like to solve it another way by adding channels to the Apollo or getting the Optical in working eventually so that I can go between teaching and recording with stereo sound without changing my routing.

    Scratch, that is some next level usage! I will file that away in case I feel that something in the Kemper fx chain may beat something in the logic plug in realm. I'm still on the surface level usage with this thing but happy to learn.


  • Honestly I doubt Zoom is stereo. Just do it mono XLR in the input 1 and then put a microphone in input 2. Select Universal Audio as your input in Zoom. Done.