Connection from Kemper to audio interface question???

  • Hello,


    First post. Hope my question is not too simple.


    When connecting the Kemper in stereo to my audio interface, I want to use the XLR outputs (Left and Right) of the Kemper into the 1/4 inch inputs of my audio interface. My audio interface needs the 1/4 inch input connections in order to be line level. For the cables, should the 1/4 inch side be balanced or unbalanced?


    Thanks

  • As above - you should use the balanced XLR outputs from the Kemper into the TRS sockets of your interface, using XLRf-TRS cabling. Alternatively, you *may* be able to PAD the XLR/Mic inputs down on your interface to bring the level down to something that doesn't clip, or you could run the output of the Kemper into a DI box if you have one, to take bal Line down to bal Mic.


    Either of these solutions is preferable to running TS (unbal) instrument cabling as the latter doesn't reject the interference/noise that can be picked up and the level will be 6dB down from bal Line as the extra XLR pin (3) will be grounded or not connected. If this is just a quick demo recording just to get some ideas down or stick on YouTube at 128kbps I wouldn't worry too much, but if you're committing something to a recording that you're going to want to mix later, stay balanced.


    I guess you have an interface with combo XLR/Jack inputs that auto-switches between Mic and Line modes depending on the physical connector, trying to be helpful? A lot of Focusrite units are doing this now.

  • As above - you should use the balanced XLR outputs from the Kemper into the TRS sockets of your interface, using XLRf-TRS cabling. Alternatively, you *may* be able to PAD the XLR/Mic inputs down on your interface to bring the level down to something that doesn't clip, or you could run the output of the Kemper into a DI box if you have one, to take bal Line down to bal Mic.


    Either of these solutions is preferable to running TS (unbal) instrument cabling as the latter doesn't reject the interference/noise that can be picked up and the level will be 6dB down from bal Line as the extra XLR pin (3) will be grounded or not connected. If this is just a quick demo recording just to get some ideas down or stick on YouTube at 128kbps I wouldn't worry too much, but if you're committing something to a recording that you're going to want to mix later, stay balanced.


    I guess you have an interface with combo XLR/Jack inputs that auto-switches between Mic and Line modes depending on the physical connector, trying to be helpful? A lot of Focusrite units are doing this now.

    Thanks! Yes, Focusrite interface. If I put an XLR cable into the input of the interface the interface will interpret that at mic level.


    I actually have a S/PDIF input and output as well on the Focusrite. Would it better to use that instead? I don't know a lot about using S/PDIF.


    Thanks.



  • Either option is going to work, they just have different considerations. SPDIF will require a dedicated 75 Ohm cable (i.e. not just an RCA phone you have for consumer analogue equipment), and the Kemper has to be the clock master, as it can't sync to incoming clock. You'll need to pick your preferred sample rate (44.1/48 kHz etc.) to clock your DAW.


    Be careful re-clocking your Focusrite with your monitors un-muted, including sample rate and source changes as I bet it doesn't lift its output relays and will go BLAT when you do this. Better to have the Kemper on first, but this can be impractical if you've already got your computer up and booted.


    Personally, I'd go analogue from the Kemper in a simple rig like this so you can forget about the re-clocking scenario above. It would be nice if there was a sync ref input on the Kemper (word clock for example) so that it could be a slave and better integrate with other systems, but meh.

  • spdif is easy as you dont have to care so much about the Levels,

    but to me Analog outs from the KPA sounds slightly better than spdif

    the Kemper has great soundingAD Converters

    That's interesting - I can believe it, but I guess the question is where in the signal chain the sounds diverge slightly. Not had my Stage long enough to do an AB on these yet, but I'm interested to have a go at this with some fancy measurement tools and see if I can spot anything :)

    Were you re-converting the main angle outs via a dedicated interface back into your DAW to compare?

  • I just listened to recordings i made, and the analog outs of the Kemper sounded

    more "alive" to me

    so no measurement which can show a diff between analog and spdif

    just my personal opinion

    Which is kinda weird, when you think of it, as you're chaining up A/D converters. Does anybody know if the Kemper does dithering on its analog outputs only? That'd explain it.


    You could try running your recorded SPDIF signal through some plugins simulating analog gear (they usually introduce a bit of noise) and/or use dithering while exporting.


    I'd try that myself, but my audio interfaces are all lacking SPDIF. *pouts*