SPDIF vs Analog outs

  • I have had my Kemper now for over 2 years and love it. One constant struggle I have with mine is the tone of SPDIF vs Analog outs. My main issue is that the Analog TRS output sounds FAR more full and beefy than the SPDIF which sounds rather tinny and congested with less fullness. I have tried many 'tweaks' to the output but nothing has made the SPDIF sound the same as Analog TRS out on my rig. I do use a EMU 1212M sound card which has both SPDIF and Analog inputs. I have made absolutely sure that the correct master clock (kemper) is selected as well as the correct sample rate. The EMU1212M does in fact lock correctly any time I connect it so I don't think there is an issue with that part.


    So i was going to post an example set of wav files but after recording via the SPDIF and playing back via the normal TRS outputs on the EMU interface.. the tinnyness and congestion is gone and it sounds like the analog outputs... WTF?! :cursing:


    I feel like my Sound card interface is to blame for the SPDIF monitoring sounding like poop but I just don't understand why. At this point I have messed around with this so much that I have given up and use the Kemper analog outs to record and jam with and it sounds great. I suppose its time to throw the EMU1212M out the window and purchase something else. I don't want to get rid of the card however.. it sounds nice and is PCI and stable which these days is near impossible to accomplish without breaking the bank.



    Any recommendations or ideas would be appreicated! I am really unhappy with SPDIF sounds on my rig.

  • After recording the wav'd recording sounds perfect and not tinny at all. The SPDIF seems to be working great but monitoring it is not sounding well.


    Page 1 Master:
    Main output - Master Stereo
    Master Output - Master Mono
    Direct Output - GIT+Processing
    SPDIF - Master Stereo

  • For me the spdif sounds better. It sounds very identical to my frfr monitoring solution. As Michael_dk adjustments in the output sections must be made experienced the same problems on initial setup.

  • For me the spdif sounds better. It sounds very identical to my frfr monitoring solution. As Michael_dk adjustments in the output sections must be made experienced the same problems on initial setup.

    Yeah I understand technically the SPDIF *should* sound better with less noise.. but it sounds thin and weak and compressed somehow. Since I know a little about recording my first instinct is to try and adjust the output gain control. In this case the Kemper is set to 0DB so that is max SPDIF out. It has got to be my interface but damn if I can figure out what is wrong. SPDIF has no settings like +4db or -10db.. so its like what could possibly be wrong?!?!


    here is what I am dealing with:


    [Blocked Image: https://dl.dropboxusercontent.com/u/29745912/emu1212m.jpg]

  • How is your monitoring being routed?


    If your soundcard supports it you should only use hardware monitoring on the soundcard (so called "zero"-latency monitoring) and disable software monitoring in your DAW, otherwise you will get an echo and phase/comb filtering effects of the DAW monitoring and the soundcard monitoring happening at once, which can lead to odd sounding effects.


    Your routing for a DAW should be either :
    a) Guitar --Input Jack--> Kemper ==SPDIF==> SoundCard (attached to PC) ==XLR/Phono==> Monitors
    or
    b) Guitar --Hi-Z Jack--> Soundcard ==SPDIF--> Kemper ==SPDIF==> SoundCard (attached to PC) ==XLR/Phono==> Monitors


    In your soundcard's control panel you should also make sure to disable any other inputs coming in from the Kemper for direct monitoring, i.e. only monitor one source so as to avoid more phase issues (if you can't do that then simply unplug any other outputs from the Kemper other than SPDIF).


    Good luck with it, you really hsouldn't notice any difference bteween the SPDIF and main outputs, unless you've modified the output settings ont he Kemper to e.g. disable the cab on one or more outputs, or set the SPDIF to be one channel clean and one channel modified etc. It's worth going through the output section to make sure that all outputs have hte same levels, EQ's, settings, no bypassing etc going on, nor space effect on one but not the other etc, if it's too much you can simply do a reset on the Kemper to revert all the settings to factory defaults.



  • +1


    Try the simple stuff first - pull out the analogue connections from the KPA and see if that changes anything. That would rule out any phasing issues between TRS and SPDIF connections.

  • I never looked at that setting, wonder why its on mono. I will change it and check things. Also I never had analog TRS plugged in at the same time as SPDIF so there wouldn't be any issues with that.


    [edit] actually that doesnt have a stereo setting..

    Also, your master stereo and your SPDIF are setup differntly from each other. One is master mono, the other is master stereo. Make sure that is rectified, you can't really compare the two results otherwise.

  • 1. Just to rectify a small mistake: The Kemper output (and input) jacks are NOT TRS, they are just TS. Not a big deal but wanted to mention it.


    2. I don't own an E-mu interface but from watching a few screenshots it seems like the PatchMix offers onboard monitoring FX. You checked that you don't use any onboard monitoring FX on one input while you don't on the other?


    3. Although I don't think you made this mistake, have you doublechecked that you're monitoring exactly same levels when using S/PDIF vs. analog?

  • Mikeb:


    I wonder if I've experienced something similar a few years back when I tried to sync my symphony orchestra rig (Mac pro, an audio interface and Vienna Symphonic Library) to my Pro Tools HD Accel rig (another Mac Pro) via SPDIF (digital patchbay and a Yamaha 02R96 mixer to Pro Tools 192 IO). Monitoring the audio during the transfer sounded awful. It was totally useless. But I really can't remember if I checked the audio quality of the playback of the tracks afterwards. I just didn't dare to trust the recording quality when the monitoring sounded like that. But then I discovered that the “monitor recording quality” changed when I chose a different master clock. I actually ended up investing in a separate monitor solution after that to avoid similar incidents again. I never found the actual culprit for this weird audio issue though, but now I'm at least careful with how I connect and sync digital units together even if the sync seems fine. I don't know if this info can be of any help to you, but it would be interesting if you could just check your set up using a different way of clocking your audio transfer. Would that be possible? I just got my Kemper a few days back, so I haven't had the chance to explore all the recording options yet. Great product though... :-)


    Cheers,
    -terje


  • hi!via spdif u convert the digital output from kemper with ur interface's converters, kempers converter to analog out is magnificent, it might be that diference between the two converters kemper vs interface...


    Yep, a year ago I tested this a bit. I have Focusrite Scarlett 18i20 audio interface and also high-end Benchmark DAC1 digital audio converter, and Focusrite own were clearly inferior to Kemper's built-in converters (Focusrite sounded a bit weak and subdued). On the other hand, there was little difference between Kemper and Benchmark DAC1 (and DAC1 have been miles better then pretty much everything else I have tried this far), so it's definitely very good and that was a pleasant surprise.


    What I do now is that I have SPDIF connected, but I use that only for recording. I use the Kemper's analog outs for all monitoring purposes.


    So my recommendation is to use Kemper's analog outs for monitoring unless you have some high-end audio interface or separate digital audio converter.

  • hi!via spdif u convert the digital output from kemper with ur interface's converters, kempers converter to analog out is magnificent, it might be that diference between the two converters kemper vs interface...



    I am assuming you mean the interface's digital to analogue converter, going to the monitors.


    Those would still be used for playing back the recording, which, as the OP said, sounds fine. So I don't think that's the problem.

  • How are you meant to even use the Kemper's own monitor outputs when using or recording with a DAW anyway?


    Pure monitor mixer? That's one way to guarantee that what you hear as you record isn't what goes down on tape...